Luminous Landscape Forum

Equipment & Techniques => Landscape & Nature Photography => Topic started by: msongs on March 15, 2014, 02:09:13 am

Title: good histogram = dark images in surf pics...
Post by: msongs on March 15, 2014, 02:09:13 am
aloha, have started doing some surf/surfer pics here in hawaii. I use a canon rebel t3i  and shoot in shutter mode and let the camera do the f stop. Tried shooting at 1000. the preview histograms always looked really well balanced and centered. when i got home I converted the canon raws into dng and loaded into CS4. the images were quite dark!. If I opened them in CS4 and did a levels check the histogram was right centered and the only slider adjustment really available made them even darker (moving the left triangle over towards the center to the edge of the histogram).

Of course surf means high contrast, dark waves and white foam so there is a learning curve for sure. I want to use a higher than 1000 shutter speed as the pics were just a bit blurry. the main issue is the dark pics tho. Using the on camera histogram does not seem to be that valuable as a reference. Should I make the settings so the in camera histogram is way over to the right more? the shutter speed is the most important setting. any suggestions?

Marshall aka Msongs
Title: Re: good histogram = dark images in surf pics...
Post by: Vladimirovich on March 15, 2014, 02:29:52 am
aloha, have started doing some surf/surfer pics here in hawaii. I use a canon rebel t3i  and shoot in shutter mode and let the camera do the f stop. Tried shooting at 1000. the preview histograms always looked really well balanced and centered. when i got home I converted the canon raws into dng and loaded into CS4. the images were quite dark!. If I opened them in CS4 and did a levels check the histogram was right centered and the only slider adjustment really available made them even darker (moving the left triangle over towards the center to the edge of the histogram).

Of course surf means high contrast, dark waves and white foam so there is a learning curve for sure. I want to use a higher than 1000 shutter speed as the pics were just a bit blurry. the main issue is the dark pics tho. Using the on camera histogram does not seem to be that valuable as a reference. Should I make the settings so the in camera histogram is way over to the right more? the shutter speed is the most important setting. any suggestions?

Marshall aka Msongs


1) in camera histogram (unless you have firmware mod from Magic Lantern which may be available or not for your Canon) = OOC JPG histogram... this is not raw histogram

2) using Adobe raw converters is not the best idea to evaluate raw histogram either - albeit with certain setting and modified profiles you can get close

3) www.rawdigger.com

it is worth it...
Title: Re: good histogram = dark images in surf pics...
Post by: ErikKaffehr on March 15, 2014, 02:43:52 am
Hi,

If you would post one of those DNGs it may be easier to help.

Best regards
Erik


aloha, have started doing some surf/surfer pics here in hawaii. I use a canon rebel t3i  and shoot in shutter mode and let the camera do the f stop. Tried shooting at 1000. the preview histograms always looked really well balanced and centered. when i got home I converted the canon raws into dng and loaded into CS4. the images were quite dark!. If I opened them in CS4 and did a levels check the histogram was right centered and the only slider adjustment really available made them even darker (moving the left triangle over towards the center to the edge of the histogram).

Of course surf means high contrast, dark waves and white foam so there is a learning curve for sure. I want to use a higher than 1000 shutter speed as the pics were just a bit blurry. the main issue is the dark pics tho. Using the on camera histogram does not seem to be that valuable as a reference. Should I make the settings so the in camera histogram is way over to the right more? the shutter speed is the most important setting. any suggestions?

Marshall aka Msongs

Title: Re: good histogram = dark images in surf pics...
Post by: Tony Jay on March 15, 2014, 02:47:42 am
Hi Marshall.

It seems as if you have discovered a truth about digital imaging: There simply is no predetermined good histogram.
From your description it is clear that you are substantially underexposing.
Your goal is never a pretty looking centred histogram.

The real goal is to maximise the light-gathering capabilities of your camera's sensor.
So, in reality, you want your histogram pushed over to the left but just shy of clipping.
The in-camera histogram is not a good judge of whether clipping has occurred for a variety of reasons, not least the fact that the histogram is derived from a JPEG derivation of the original RAW file.
To help you a bit make sure that the picture style is set to something like "Faithful" that has no changes to contrast factored in.
It makes absolutely no difference to the RAW image but it does affect how the JPEG looks, and hence the histogram that is derived from it.
Ultimately, however, it is only when you load that RAW image into a RAW converter that you will know how much headroom is really available.
My 5D Mark III gives just over a stop of light as headroom between what the in-camera histogram tells me and the histogram in Lightroom.
Your camera will be different - hence the need for experimentation.

I understand that, given the type of shooting you are doing, that you will not be shooting at base ISO even of the light is very bright because of the high shutter speeds required.
So you will have to further determine the trade-off in image quality between ISO-related noise and blurring from shutter speeds that are less than optimal.
Since most cameras that are late models have pretty good noise characteristics I would set the shutter speed to whatever is required and therefore a highish ISO and let the noise take care of itself in post-processing.

Tony Jay
Title: Re: good histogram = dark images in surf pics...
Post by: stamper on March 15, 2014, 05:22:05 am
So, in reality, you want your histogram pushed over to the left but just shy of clipping.

Tony you mean the right? :)
Title: Re: good histogram = dark images in surf pics...
Post by: Tony Jay on March 15, 2014, 06:08:51 am
So, in reality, you want your histogram pushed over to the left but just shy of clipping.

Tony you mean the right? :)
Yes I do! ETTR
R for right!
I cannot believe that I wrote it but I did - unbelievable!
Apart from being distracted a bit while typing that post there are no excuses - just really silly on my part.
Re-read the rest of my post just to make sure that there were no other stupid landmines in there but it seems otherwise OK.

Tony Jay
Title: Re: good histogram = dark images in surf pics...
Post by: LesPalenik on March 15, 2014, 07:05:41 am
In a heavy surf, I would dial +1.0 to 1.5 EV, or switch to manual exposure mode.
If you increase the exposure by 1 or 2 stops in postprocessing, you might see some noise, but as Tony mentioned, you can fix it in LR or with some Noise Reduction program.
Topaz Labs is now running a 50% promotion on their excellent DeNoise plugin.  I posted a short review of this plugin with examples on my blogsite at:
www.advantica.wordpress.com (http://www.advantica.wordpress.com)

Les


  
Title: Re: good histogram = dark images in surf pics...
Post by: msongs on March 15, 2014, 11:19:34 pm
hello,

tried to post a 2mb jpg but this site won't allow it. the original dng files are way too big. so let's see if this little tiny file will post. ok that worked ok.

tried adjusting exposure in raw, a few other things like shadow highlight to give detail to the white waters. reading around the internet the basic best exposures seem to be above 1/1000 at f8 and raising iso from 100 if that is needed. and using the highlight warning systems if the t3i has one. I know my Olympus e620 has a good one and it is almost always underexposing pictures lol
Title: Re: good histogram = dark images in surf pics...
Post by: ErikKaffehr on March 16, 2014, 12:45:40 pm
Hi,

In my favourite raw processor, LR5 I would try to push highlights all way left (providing tone mapping on the surf) and increase exposure to get good mid tones.

Best regards
Erik


hello,

tried to post a 2mb jpg but this site won't allow it. the original dng files are way too big. so let's see if this little tiny file will post. ok that worked ok.

tried adjusting exposure in raw, a few other things like shadow highlight to give detail to the white waters. reading around the internet the basic best exposures seem to be above 1/1000 at f8 and raising iso from 100 if that is needed. and using the highlight warning systems if the t3i has one. I know my Olympus e620 has a good one and it is almost always underexposing pictures lol
Title: Re: good histogram = dark images in surf pics...
Post by: nma on March 16, 2014, 02:01:48 pm
aloha, have started doing some surf/surfer pics here in hawaii. I use a canon rebel t3i  and shoot in shutter mode and let the camera do the f stop. Tried shooting at 1000. the preview histograms always looked really well balanced and centered. when i got home I converted the canon raws into dng and loaded into CS4. the images were quite dark!. If I opened them in CS4 and did a levels check the histogram was right centered and the only slider adjustment really available made them even darker (moving the left triangle over towards the center to the edge of the histogram).

Of course surf means high contrast, dark waves and white foam so there is a learning curve for sure. I want to use a higher than 1000 shutter speed as the pics were just a bit blurry. the main issue is the dark pics tho. Using the on camera histogram does not seem to be that valuable as a reference. Should I make the settings so the in camera histogram is way over to the right more? the shutter speed is the most important setting. any suggestions?

Marshall aka Msongs


I feel you pain but I would work some more on your exposure with histograms.  As some have noted, the histogram from the in-camera jpeg is sometimes inaccurate. To overcome this type of problem on my Canon 5Dii, I reduce the jpeg parameters with white balance on auto, contrast is low, saturation and sharpening are low. It makes for a crummy image on the preview display, washed out, but now the histogram is much more like what you will see in the raw developer.  You should do a few experiments in the surfing environment to verify what jpeg settings give the most accurate raw histogram, comparing with your raw developer. I find that my jpeg and raw histograms are very close. This means that in the surfer environment I would take a couple of trial shots and view the histograms, making any necessary exposure adjustments so that it is in accord with ETTR. I ignore the preview completely, except for compositional information.This works 100% of the time. It does not follow that the image using default settings in your raw developer will look perfect. All that I guarantee is that all the tonal values will fit in the usable range, with highlights in the appropriate far right of the histogram.  That could result in your raw developer rendering the default image with bright, well exposed, highlights and dark values for most everything else. This is OK. Merely reduce the highlight slider and maybe the whites to taste, while boosting the shadow slider.

Let us know how this works for you.
 
Title: Re: good histogram = dark images in surf pics...
Post by: Tony Jay on March 16, 2014, 04:24:46 pm
Looking at these images all they require is an increase in exposure and a bit of a tweak in contrast in post-processing.
My goal would be to bring the breaking surf to just shy of clipping.

Tony Jay
Title: Re: good histogram = dark images in surf pics...
Post by: BAB on March 17, 2014, 09:58:06 am
Bring your laptop to the beach take a shot crop the area you want the perfect exposure and look at the histogram in lightroom then adjust the exposure on your camera and shoot again until you know what is perfect for your sensor on that camera. If the sunny day is the same sunny day tomorrow and your at the same angle to the light you will know your sensor needs to be set +2.5 EV to make the exposure you want.

I would also suggest a slightly longer focal length
Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 17, 2014, 10:51:58 am
when i got home I converted the canon raws into dng and loaded into CS4. the images were quite dark!.

IF you shoot raw, the histogram on the camera is a big fat lie!
This may help understanding why and more about histograms:

Everything you thought you wanted to know about Histograms

Another exhaustive 40 minute video examining:

What are histograms. In Photoshop, ACR, Lightroom.
Histograms: clipping color and tones, color spaces and color gamut.
Histogram and Photoshop’s Level’s command.
Histograms don’t tell us our images are good (examples).
Misconceptions about histograms. How they lie.
Histograms and Expose To The Right (ETTR).
Are histograms useful and if so, how?

Low rez (YouTube): http://www.youtube.com/watch?v=EjPsP4HhHhE
High rez: http://digitaldog.net/files/Histogram_Video.mov
Title: Re: good histogram = dark images in surf pics...
Post by: Vladimirovich on March 17, 2014, 11:01:07 am
and look at the histogram in lightroom

www.rawdigger.com , not LR/ACR , is the tool to study raw histograms nowadays...

Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 17, 2014, 11:06:33 am
www.rawdigger.com , not LR/ACR , is the tool to study raw histograms nowadays...

Study sure. But if you use LR and have to process images, then that's unnecessary. Learn to use the camera to produce well exposed raw data. I recall spending decades doing this on film when few if any photographers had heard the word Histogram! Then normalize in LR and move on. The histogram is the histogram and histograms really don't provide much info that's useful other than clipping, which LR will easily show you on the actual image. Far more useful to SEE on the image what clips and where then trying to decipher a histogram. At least if your goal is to produce a pleasing image. For some scientific or analytical work, by all means 'study' the histogram.
Title: Re: good histogram = dark images in surf pics...
Post by: bjanes on March 17, 2014, 11:59:31 am
Study sure. But if you use LR and have to process images, then that's unnecessary. Learn to use the camera to produce well exposed raw data. I recall spending decades doing this on film when few if any photographers had heard the word Histogram! Then normalize in LR and move on. The histogram is the histogram and histograms really don't provide much info that's useful other than clipping, which LR will easily show you on the actual image. Far more useful to SEE on the image what clips and where then trying to decipher a histogram. At least if your goal is to produce a pleasing image. For some scientific or analytical work, by all means 'study' the histogram.

LR/ACR, at least with PV2012 and the default tone curve, is not good for evaluating overexposure since automatic highlight recovery is employed and an exposure offset is used. With Nikon cameras it +0.5 EV for the D3 and + 0.35 for the D800e. With ACR one can get a reasonable representation of the raw file by adjusting exposure to offset the baseline exposure value and using a linear tone curve by setting the sliders on the main page all to zero and setting the tone curve to linear.

Added in edit (3/18/2014). One must use PV2010 when using this method.

Rawdigger can show overexposed areas as well as the rendered image, and is not limited to presentation of the histogram.

Here is an image taken by the D3 with overexposed yellows as shown by Rawdigger:
(http://bjanes.smugmug.com/Photography/ETTRColor/i-49SwWv6/0/XL/CBG_062108_0009-20140317-101506-RawDigger-ScreenShot-XL.png)

And by ACR with the required adjustments. I should have rendered into ProphotoRGB to prevent saturtion clipping rather than into Adobe RGB, but the clipping is reasonably shown.
(http://bjanes.smugmug.com/Photography/ETTRColor/i-jmWWvNb/0/XL/11_ACR8_aRGB-XL.png)

Here is another exposure that is not clipped in the raw file as shown by Rawdigger:
(http://bjanes.smugmug.com/Photography/ETTRColor/i-3sDr5ms/0/L/Img10_RD_Histogram-L.png)

However clipping is shown in ACR even with the above mentioned adjustments. The clipping in the red channel is likely due to white balance with a red multiplier greater than unity. The green channel shows spurious clipping in ACR.
(http://bjanes.smugmug.com/Photography/ETTRColor/i-BxxHzrd/0/XL/Img10_ACR_PV2010_Lin-XL.png)

I agree that Rawdigger is the preferred tool for evaluating raw files.

Bill
Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 17, 2014, 12:28:47 pm
LR/ACR, at least with PV2012 and the default tone curve, is not good for evaluating overexposure since automatic highlight recovery is employed and an exposure offset is used.
But if that's the process used to render the raw's, how is that a problem?
If one wants to understand the effect of the exposure + processing on their raws, and assuming they want to use LR/ACR, I don't see how this is a problem. The rendering, the clipping (or lack of clipping both exposure and saturation) are the reality of what is currently being seen in the raw converter. Why not simply deal with the processing as we've done in the past with film? That being, your exposure and processing are tied at the hip. Bracket under controlled lighting. Bring raws into LR/ACR. Use PV2012 or not, depending on your preference. What you see is what you get here: exposure plus processing. What am I missing in such an approach?
Title: Re: good histogram = dark images in surf pics...
Post by: Petrus on March 17, 2014, 12:38:36 pm
If the pictures turn out consistently too dark, exposure metering is doing a wrong evaluation of the subject, really nothing more to it. Quite usual, actually, if the subject is lighter or darker than average, for which the exposure is calibrated. Just simply turn the exposure compensation dial to +1 or +1.5, problem is likely to be fixed, that is why cameras have that function. No need to dwell deeply into conversion theories or purchase better/different RAW converters.
Title: Re: good histogram = dark images in surf pics...
Post by: Vladimirovich on March 17, 2014, 12:39:29 pm
But if that's the process used to render the raw's, how is that a problem?

the problem is - people shall not think in terms of LR/ACR w/o understanding what LR/ACR does with the data and what is data that LR/ACR deals with... why do you want to cripple their knowledge ?
Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 17, 2014, 12:41:35 pm
If the pictures turn out consistently too dark, exposure metering is doing a wrong evaluation of the subject, really nothing more to it. Quite usual, actually, if the subject is lighter or darker than average, for which the exposure is calibrated. Just simply turn the exposure compensation dial to +1 or +1.5, problem is likely to be fixed, that is why cameras have that function. No need to dwell deeply into conversion theories or purchase better/different RAW converters.
I agree totally up to the point about better/different raw converters. I don't see how we can separate exposure from processing. But yes, your suggestion about expsoure compensation is exactly how I handle ETTR. The first part is of course gauging via brackting how much to compensate and to do that, at least I have to bring the raw's into LR and see how far I can go before I've really blown out highlights I want to retain. From there, it's exposure 101.
Title: Re: good histogram = dark images in surf pics...
Post by: Vladimirovich on March 17, 2014, 12:42:29 pm
If the pictures turn out consistently too dark, exposure metering is doing a wrong evaluation of the subject, really nothing more to it. Quite usual, actually, if the subject is lighter or darker than average, for which the exposure is calibrated. Just simply turn the exposure compensation dial to +1 or +1.5, problem is likely to be fixed, that is why cameras have that function. No need to dwell deeply into conversion theories or purchase better/different RAW converters.

I'd say no need to use raw converters at all - just use camjpg
Title: Re: good histogram = dark images in surf pics...
Post by: Vladimirovich on March 17, 2014, 12:45:48 pm
I agree totally up to the point about better/different raw converters. I don't see how we can separate exposure from processing. But yes, your suggestion about expsoure compensation is exactly how I handle ETTR. The first part is of course gauging via brackting how much to compensate and to do that, at least I have to bring the raw's into LR and see how far I can go before I've really blown out highlights I want to retain. From there, it's exposure 101.
and I using LR Rawdigger can tune real time (pre shot) blinkies (E-M1) or zebra (A7) to show me when clipping starts in raw with less than 1/3 EV precision and understand what is the headroom in raw when I do spot metering.. that is I don't need clueless histogram in LR/ACR at all... that is exposure 101 nowadays.
Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 17, 2014, 12:46:16 pm
the problem is - people shall not think in terms of LR/ACR w/o understanding what LR/ACR does with the data and what is data that LR/ACR deals with... why do you want to cripple their knowledge ?
No but I don't see that as very relevant. ACR/LR does as we both agree, do something with that data. Unless we decide not to use that specific converter, it's going to do what it's going to do and that IS part of the entire process. Or to put it another way, if we agree the OP and other's will use LR/ACR, and Rawdigger shows something vastly different from LR/ACR, what's the user to do? They have to take that processing into account. Just as a lab's E6 processing in LA may differ from E6 processing in NY. Yes, in a perfect world, they would be identical. At least when I shot a lot of E6 film, it always went to one lab (A&I Color), I always ran exposure and filter tests from each emulation batch I'd buy. And I did have to alter the process a bit. Again, I'm wondering HOW one can separate exposure and processing without tieing yourself up in knots.
Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 17, 2014, 12:48:24 pm
that is I don't need clueless histogram in LR/ACR at all... that is exposure 101 nowadays.
Agreed. And further, seeing clipping in color or channel OVER the image in LR/ACR is vastly more useful than looking at a Histogram. The problem becomes when the clipping really is clipped data and as you say, that's exposure 101. No histogram needed in either product. By and large, Histograms have been over sold.
Title: Re: good histogram = dark images in surf pics...
Post by: Bart_van_der_Wolf on March 17, 2014, 12:56:56 pm
But if that's the process used to render the raw's, how is that a problem?

Because it doesn't tell what is going on, and how to address the issue at the core (correct exposure). Besides, there are other converters than LR/ACR which do show the real situation without the 'PV2012 black magic'.

Quote
If one wants to understand the effect of the exposure + processing on their raws, and assuming they want to use LR/ACR, I don't see how this is a problem.

Because one doesn't learn to address the real fundamental issue with exposure, just how LR/ACR handles it. If one switches to another (superior) Raw converter one may learn all of a sudden that the Raw files were incorrectly exposed from the start, potentially beyond correction with anything else than LR/ACR, or with sub-optimal exposure.

Quote
What am I missing in such an approach?

An unbiased advice? The truth (not just the one according to Adobe but), the whole truth, and nothing but the truth?
It's just like with politicians, they don't lie, they just do not tell the whole truth.

Cheers,
Bart
Title: Re: good histogram = dark images in surf pics...
Post by: bjanes on March 17, 2014, 01:05:59 pm
LR/ACR, at least with PV2012 and the default tone curve, is not good for evaluating overexposure since automatic highlight recovery is employed and an exposure offset is used. With Nikon cameras it +0.5 EV for the D3 and + 0.35 for the D800e.

But if that's the process used to render the raw's, how is that a problem?
If one wants to understand the effect of the exposure + processing on their raws, and assuming they want to use LR/ACR, I don't see how this is a problem. The rendering, the clipping (or lack of clipping both exposure and saturation) are the reality of what is currently being seen in the raw converter. Why not simply deal with the processing as we've done in the past with film? That being, your exposure and processing are tied at the hip. Bracket under controlled lighting. Bring raws into LR/ACR. Use PV2012 or not, depending on your preference. What you see is what you get here: exposure plus processing. What am I missing in such an approach?

Andrew,

I do use LR PV2012 to render most of my raw files with good results, but it helps to know how the converter is handling the raw file. If one is exposing to the right and using the LR/ACR histogram to judge exposure and you don't take the offset into account, you may not  be exposing optimally.

Bill
Title: Re: good histogram = dark images in surf pics...
Post by: bjanes on March 17, 2014, 01:12:14 pm
Because one doesn't learn to address the real fundamental issue with exposure, just how LR/ACR handles it. If one switches to another (superior) Raw converter one may learn all of a sudden that the Raw files were incorrectly exposed from the start, potentially beyond correction with anything else than LR/ACR, or with sub-optimal exposure.

Bart,

I do know that you are no fan of Adobe products, but the LR workflow does work well for many of us and the file handling and printing features are worth a minimal loss of image quality. For exhibition prints or special images, one still has the raw file and might wish to use better tools. A much requested feature of ACR is to have a switch to show the raw histogram such as is available in Raw Therapee. Eric Chan, are you listening?

Bill
Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 17, 2014, 01:13:04 pm
Because it doesn't tell what is going on, and how to address the issue at the core (correct exposure). Besides, there are other converters than LR/ACR which do show the real situation without the 'PV2012 black magic'.
Exactly, the processing is part of the total equation. What's going on in LR is what's going on in LR, the product we are supposedly using. Switch products and yes, I expect a different result to some degree. The processing is different. Are you saying that Rawdigger IS the ultimate info, and that it's raw converter processing agnostic? Even if true, you still can't separate the processing which is converter specific. So perhaps if this product is free and you can run it, seeing the bracket test would tell you something about actual raw clipping separate from processing. Unless you decide it's your raw converter of choice, you simply have to move past it and see the results of the bracket in the converter you intend to use. Rawdigger isn't necessary, it's an interesting (for some) data point.

One could say, use Rawdigger to find true raw clipping but you to then move the data into the converter of choice and work from there no?

Let's use the E6 analogy. Lab in NY that I don't use conforms to the E6 standards exactly, A&I lab in LA that I use is off. But I'm targeted to A&I, the processing. Knowing what the E6 standard aim point is and who hits it (Rawdigger) is interesting. But it doesn't help me at all as I'm using A&I in LA (LR/ACR). IF I move to NY, I'll consider my next move. That move has to involve the processing.
Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 17, 2014, 01:19:17 pm
Here is an image taken by the D3 with overexposed yellows as shown by Rawdigger:
I don't use this product so forgive me if this is a stupid question. You say overexposed yellow. I assume on channel is blown out. Based on what color space?
Title: Re: good histogram = dark images in surf pics...
Post by: Bart_van_der_Wolf on March 17, 2014, 01:53:12 pm
I do know that you are no fan of Adobe products, but the LR workflow does work well for many of us and the file handling and printing features are worth a minimal loss of image quality.

Hi Bill,

I use Photoshop every day, and I occasionally use Lightroom. So it's not that I don't like Adobe products, but I do have some reservations about the Raw conversion quality. When I do use LR/ACR for Raw conversion, it's mainly for convenience but not for quality.

Since I usually do not have to process large volumes, I tend to aim for quality, which steers me to e.g. Capture One Pro (also allows LCC correction with automatic dust removal), or RawTherapee (with Amaze or other dedicated (e.g. for High ISO noise) conversion algorithms and CIECAM color corrections), for Raw conversion, and then to Photoshop for layer based postprocessing.

However, it all starts with optimized exposure, and learning from experience how to achieve that in camera is important. When a Raw converter becomes an obstacle to learning that optimal exposure and delivers sub-optimal raw conversions to boot, I'll warn others about that because I think they should know the full story. When people are fully informed, they can choose whatever compromise they want. I don't really care what others use, but I do care when people are being spoon-fed only half truths.

The OP is experiencing an issue, maybe caused by exposure technique, that can presumably be solved with proper technique. He is probably better helped by solid advice than by ways to mask/hide his fundamental issues by using a tool 'XYZ'.

Cheers,
Bart
Title: Re: good histogram = dark images in surf pics...
Post by: bjanes on March 17, 2014, 03:03:23 pm
I don't use this product so forgive me if this is a stupid question. You say overexposed yellow. I assume on channel is blown out. Based on what color space?

This would be the red channel is focally blown out to the extent of 3.6% of the red pixels as shown by Rawdigger. The color space would be that of the raw file (if you accept a raw file as having a color space--I would prefer not to re-argue that topic  :)). When the file is rendered into ProphotoRGB with ACR, there is strong clipping of the red channel due white balance (Rawdigger reports the red multiplier as 1.70 for the as shot white white balance). If one were rendering with DCraw, one could use the -H 1 option to use multipliers less than or equal to unity (see Guillermo Luijk (http://www.guillermoluijk.com/tutorial/dcraw/index_en.htm)). With ACR one can use negative exposure to obtain the same effect (AFAIK).

Bill
Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 17, 2014, 03:05:39 pm
The color space would be that of the raw file (if you accept a raw file as having a color space--I would prefer not to re-argue that topic  :)).
I don't want to go there either. But some assumption is made, that would affect the results right? Or there is a margin after which, no assumed color space could account for this being anything but clipping?
Title: Re: good histogram = dark images in surf pics...
Post by: Vladimirovich on March 17, 2014, 04:39:32 pm
He is probably better helped by solid advice than by ways to mask/hide his fundamental issues by using a tool 'XYZ'.

Ceterum censeo Carthaginem esse delendam (c)
Title: Re: good histogram = dark images in surf pics...
Post by: Vladimirovich on March 17, 2014, 04:42:18 pm
A much requested feature of ACR is to have a switch to show the raw histogram such as is available in Raw Therapee. Eric Chan, are you listening?
it is not going to happen because the whole point of Adobe's approach is to move away from raw data as soon as possible and perform as little operations there as possible...
Title: Re: good histogram = dark images in surf pics...
Post by: Vladimirovich on March 17, 2014, 04:53:25 pm
Are you saying that Rawdigger IS the ultimate info

as of today it is a the best usable tool to study your camera in terms how exposure and gain affects the raw data... now - that does not mean that raw converter is irrelevant - as many people many times stated here and elsewhere (including people developing rawdigger) you need to pay attention to what is your raw converter - because different raw converters might have different issues when exposure correction is performed (for example twisted DCP profiles) or for example some raw converters are not that good in handling the colors where raw is clipped in (1, 2, + channels), etc...

Title: Re: good histogram = dark images in surf pics...
Post by: msongs on March 20, 2014, 03:57:02 am
hey thanks to all the interesting information you have posted. will be doing some more surf pics next week using info from the web, youtube, and here. hope to get better results on exposure and all. its a drag using a fast shutter speed and then the camera wont take a pic because it cant set an f/stop lol.  I guess that's where exposure compensation comes in. thanks again tho.
Title: Re: good histogram = dark images in surf pics...
Post by: hjulenissen on March 20, 2014, 05:31:58 am
If the pictures turn out consistently too dark, exposure metering is doing a wrong evaluation of the subject, really nothing more to it. Quite usual, actually, if the subject is lighter or darker than average, for which the exposure is calibrated. Just simply turn the exposure compensation dial to +1 or +1.5, problem is likely to be fixed, that is why cameras have that function. No need to dwell deeply into conversion theories or purchase better/different RAW converters.
I don't think that image brightness should be solved by in-camera exposure. When operating the camera, I want to maximize the quality of recorded info (within subjective and practical constraints).

I might like to _render_ the image as e.g. high-key, but that can be better and more predictably solved in my raw editor, rather than risking clipping one or more camera channels.

As cameras get more DR, it makes sense that the exposure system "spends" this DR for both highlight headroom and noise footroom. Thus, "middle gray" might be positioned further away from highlights in 2015 cameras than it was in 2005 cameras.

-h
Title: Re: good histogram = dark images in surf pics...
Post by: jjj on March 20, 2014, 06:49:31 am
If the pictures turn out consistently too dark, exposure metering is doing a wrong evaluation of the subject, really nothing more to it. Quite usual, actually, if the subject is lighter or darker than average, for which the exposure is calibrated. Just simply turn the exposure compensation dial to +1 or +1.5, problem is likely to be fixed, that is why cameras have that function. No need to dwell deeply into conversion theories or purchase better/different RAW converters.
I was just about to say the same. Learn to use the camera metering properly or maybe even try a light meter.
Also unless the sun is darting out from behind clouds at random intervals, you can set the camera manually and leave the exposure alone. Even easier than faffing exposure compensation.
Title: Re: good histogram = dark images in surf pics...
Post by: jjj on March 20, 2014, 06:55:19 am
I don't think that image brightness should be solved by in-camera exposure. When operating the camera, I want to maximize the quality of recorded info (within subjective and practical constraints).
Which is set by in-camera exposure.  ::)

Quote
I might like to _render_ the image as e.g. high-key, but that can be better and more predictably solved in my raw editor, rather than risking clipping one or more camera channels.

As cameras get more DR, it makes sense that the exposure system "spends" this DR for both highlight headroom and noise footroom. Thus, "middle gray" might be positioned further away from highlights in 2015 cameras than it was in 2005 cameras.
And you do that by getting the 'correct' exposure in camera. 'Correct' exposure depends entirely on how you want image to look.
Don't like ETTR myself for example. Yes it may collect more information, but I'm a photographer not a forensic analyst, so I don't get upset by my shadows being black as that's maybe how I want them to look.  :)
Title: Re: good histogram = dark images in surf pics...
Post by: hjulenissen on March 20, 2014, 07:17:22 am
Which is set by in-camera exposure.  ::)

 And you do that by getting the 'correct' exposure in camera. 'Correct' exposure depends entirely on how you want image to look.
Don't like ETTR myself for example. Yes it may collect more information, but I'm a photographer not a forensic analyst, so I don't get upset by my shadows being black as that's maybe how I want them to look.  :)
I think that when you think about the difference between "exposure" and "brightness", you will realize that camera manufacturers lump these two related concepts together for no apparent good reasons (at least for raw shooters, but then raw shooters seems to not be the main focus of manufacturers anyways).
http://www.cambridgeincolour.com/tutorials/camera-metering.htm
http://en.wikipedia.org/wiki/Middle_gray

If you want large parts of your scene rendered very bright (on paper, display), I can see little reason to clip (one or more channels of) the camera sensor to achieve this. A better method would be to expose just like an audio engineer would adjust mixing console input levels (capture the performance, sans clipping), then do whatever editing after the fact.

There are situations where clipping in camera is a sensible compromise, but again, I find that the camera exposure system is more like a relic from the 80s, than the tool one might hope for in 2014.

People have made all kinds of work-arounds for this. ala: "On Nikon cameras, I apply +1.5 stop of EC when doing green landscape". "On Sony cameras, I do -0.5 stop of EC when shooting the night sky". "I always shoot each scene a number of times, inspecting the in-camera preview for blinkies before readjusting exposure". While these no doubt work for people making great photographies, it is hardly an intuitive or user-friendly method of working.

-h
Title: Re: good histogram = dark images in surf pics...
Post by: jjj on March 20, 2014, 09:18:03 am
I think people are over complicating things here. Learn how to manually expose correctly for your own purposes and equipment and you do not have to use exposure compensation.
As for your audio analogy how would you you know what levels to set if you are recording in situations where the volume varies as much as light levels do? It's not strictly analogous anyway as you can capture a shot with two very different exposures and still get a good photo. They may differ certainly, but both can still be good. There only tends to be a good recording and a bad recording, there's not really an equivalent of a high key and a low key image in recording. In music yes, but not the recording itself.

When using slide which is way less forgiving of exposure variation that raw files, I'd simply take an exposure off my hand and add 2/3rds of a stop and got slides just how I liked them. Very simply, very effective. And if you care enough about exposure for outdoor work you should learn the Sunny 16 rule (https://en.wikipedia.org/wiki/Sunny_16_rule) and learn to judge by eye. Quite useful.
Just tested it in fact, I took some shots out of my office window, firstly by guessing exposure [iso 100, 1/100 at f9] and was spot on, then I used auto and moved shot several different framings of scene. Auto [TV] gave me 1/100 at f7.1, f9, f11, f13 despite the light not changing in the slightest. Scene was mostly trees, hills, a few houses and some sky. This is why I usually can't be bothered with auto, too much faff, not less faff.
Auto exposure is hardly likely to have improved since the 80s as the same problems will always be there, the camera cannot know what you require from a scene in exposure terms, just like a camera does not know where you want point of focus to be. It can make a good guess at both and for mundane shots it's probably fine, most of the time. The only AF I've ever really been impressed with was the one on the Canon EOS 3, because it was eye controlled and worked really well. A shame it's not on more modern cameras, same goes for the clever spot metering on the OM4/OM3.
Title: Re: good histogram = dark images in surf pics...
Post by: hjulenissen on March 20, 2014, 09:44:19 am
I think people are over complicating things here. Learn how to manually expose correctly for your own purposes and equipment and you do not have to use exposure compensation.
With photography software and cameras alike working actively to not tell you what is going on (and to mask issues like excessive noise or clipping), it can be hard to get feedback on what you are doing.

Of course, if the end-result is "good enough" and that is what you are after, then everything is fine.
Quote
As for your audio analogy how would you you know what levels to set if you are recording in situations where the volume varies as much as light levels do?
With digital, you try to maximize levels while allowing for some headroom to avoid clipping. I guess it comes down to experience and gut-feeling based on some level of technical understanding (similar to photography?).
Quote
It's not strictly analogous anyway as you can capture a shot with two very different exposures and still get a good photo. They may differ certainly, but both can still be good. There only tends to be a good recording and a bad recording, there's not really an equivalent of a high key and a low key image in recording. In music yes, but not the recording itself.
I think that one exposure is "ideal" in the sense that it maximize information about the scene. There are modifications of this, depending on how much motion blur/DOF/diffraction limits your choice in exposure. For a perfectly still, softly lit scene and using a tripod, there is a wide range of exposure times that could be chosen, but only one that makes the highlights barely touch the sensor saturation level.

Just like in the case of music, (for the limited scenario drawn), this is what you want. And just like music, allowing for some headroom makes it a lot easier to avoid blowing the whole thing.

One critique of ETTR (as I have understood it) is that exposure tends to be about optimizing many (partially) conflicting goals, and that putting too much emphasis on one is counter productive.
Quote
Auto exposure is hardly likely to have improved since the 80s as the same problems will always be there, the camera cannot know what you require from a scene in exposure terms, just like a camera does not know where you want point of focus to be. It can make a good guess at both and for mundane shots it's probably fine, most of the time. The only AF I've ever really been impressed with was the one on the Canon EOS 3, because it was eye controlled and worked really well. A shame it's not on more modern cameras, same goes for the clever spot metering on the OM4/OM3.
A camera cannot know how much motion blur or how much DOF you want. Those are artistic choices, and they somehow have to be input (or guessed). Within those confines, a camera can pretty safely assume that the user does not want to have visible sensor clipping or excessive noise.

-h
Title: Re: good histogram = dark images in surf pics...
Post by: Petrus on March 20, 2014, 10:12:15 am
Auto exposure is hardly likely to have improved since the 80s


same goes for the clever spot metering on the OM4/OM3.

There has been massive improvement in autoexposure systems since eighties. At that time there basically were only full screen averaging, semi spot metering or fixed zones (middle, 4 segments around it, usually the top one slightly damped). Now cameras can have many variable segments with (semi) intelligent guessing about the subject, and focus point can be given extra weight in exposure calculation. I shoot 95% automatic now, if the exposure is off, I usually rather correct with exposure compensation than turn to manual. I might dial in some compensation even before starting to shoot when I know AE will not nail it.

About Olympus OM3/OM4: YES, it had the best (spot) metering of any film era camera. Place the spot on the light-side cheek, adjust the exposure to +2/3, Bingo!
Title: Re: good histogram = dark images in surf pics...
Post by: nma on March 20, 2014, 10:44:50 am
The answers to the seemingly simple questions regarding " good histogram = dark images in surf pics..." have become very confusing to me. DigitalDog seems to be arguing that there is no absolute in evaluating exposure because it is intertwined with the raw converter. Others argue that Rawdigger can tell you something important. Still others rely on rules of thumb left over from the days of slide film.  And still others rely on the "blinkies" derived from the in-camera jpeg. Then there is the claim that the histogram is not very useful, perhaps even misleading.

Here are some PRACTICAL arguments for further discussion:

1. If you have a good histogram using a linear tone curve (in your raw converter), meaning the dynamic range of the scene is encompassed so the elements fall between 1 and 255 (or whatever the number of elements on the abscissa) then it should be possible to adjust the levels in the raw converter to achieve an optimal rendering. I want to add that the highlight end of the histogram should be close to the far right, otherwise it is not a good histogram. No clipping.

2. If you have a good histogram and the image is dark when you import into your raw converter, this does not indicate a fault in your exposure.  This means the raw converter defaults are not optimal for rendering your image.  Merely adjust the levels of the converter to taste.

3. The "blinkies" are an indicator but since they rely on the jpeg and the in-camera jpeg settings, they are not a reliable indicator of clipping in the raw image.

4. Someone should explain how you can have a "good histogram" using a linear tone curve and not have the optimal exposure possible given the lighting conditions. I do understand that you could purposely deviate from that exposure level to emphasize the shadow values, for example, but that is not what I mean by an optimal exposure.

Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 20, 2014, 10:46:40 am
I think people are over complicating things here.
No, you just find it complicated. It's really exposure 101, you're probably not there yet. Re-read what hjulenissen wrote, it's spot on:
Quote
I think that one exposure is "ideal" in the sense that it maximize information about the scene.
Exactly! ETTR is the beginning of the process of producing that. What's the actual sensitivity of the sensor and the role of ISO settings? What do I have to do from what the meter recommendation (again for a JPEG or film) to produce maximum information in the raw? Simple exposure and development testing as we did when shooting film. Nothing complicated about it, it's part of photography from the day it was invented!

There is one optimal, correct, ideal exposure for any scene with of course input by the image creator (espeically if the scene's DR is wider than what the camera can capture). ETTR is simply about providing that by ignoring the incorrect meter/expsoure/development (for JPEG) seen on the camera histogram. The 'to the right' means compensate because you're under exposing the raw data by correctly exposing for the JPEG. If you have a false understanding that the two should be treated the same, you fail to understand the differences in the data, encoding, oh, I'm probably going over your head, sorry. Bottom line is, just as you would never treat a neg 'rated' at ISO 400 the same as a chrome 'rated' at ISO 100 until you tested exposure+development to produce the best results, you don't do the same with digital capture.

Now if you want to point a meter, reflective or incident and treat film, JPEG, raw, any ISO, and the development the same and expect the same results, you clearly don't understand exposure and development, again photography 101.

ETTR should just be called 'proper exposure for raw data' or whatever you want to name it. The only so called conflicting goals is being forced to under expose (and over develop, at the expense of data qualty) because you don't have enough light to fully embrace ETTR, correct exposure. In the film days we DID have to do this and we did see the result; more grain. Stopping the action or producing better data, any photographer will also understand they have to push the process, grain/noise as the net result. Lesser of two evils and again, photography 101.

Quote
There has been massive improvement in autoexposure systems since eighties.
The tools may be better, but the photographer who doesn't understand what they are being told and follows the advise incorrectly are not aided here. The better metering you speak of isn't going to help the raw shooter if it's based on the JPEG and they do not implement ETTR.

Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 20, 2014, 11:03:04 am
The answers to the seemingly simple questions regarding " good histogram = dark images in surf pics..." have become very confusing to me. DigitalDog seems to be arguing that there is no absolute in evaluating exposure because it is intertwined with the raw converter.
Not quite. I think RawDigger, which I downloaded, looks very interesting but I don't think you have to use it to produce your goals of optimal exposure and development. I'm suggsting too you take baby steps and try nailing exposure + development in the raw converter of you choice. That may make a huge difference in quality.
Quote
1. If you have a good histogram using a linear tone curve (in your raw converter), meaning the dynamic range of the scene is encompassed so the elements fall between 1 and 255 (or whatever the number of elements on the abscissa) then it should be possible to adjust the levels in the raw converter to achieve an optimal rendering. No clipping.
First I'd shy away from the Histogram in LR and instead using the clipping overlay technique outlined in my video and elsewhere. Here you can SEE all the pixels that clip both tone and saturation. You may very well decide some areas should be clipped and you have every right to. Again, I'd bracket some scenes, ideally under controlled lighting and see how much compensation or ETTR off the recommend exposure you need. Outlined here: http://www.digitalphotopro.com/technique/camera-technique/exposing-for-raw.html
Quote
2. If you have a good histogram and the image is dark when you import into your raw converter, this does not indicate a fault in your exposure. This means the raw converter defaults are not optimal for rendering your image.  Merely adjust the levels of the converter to taste.
It could indicate a falut in your exposure, it depends on the current rendering settings. With ETTR, you'll mostly see images that appear at least initially to be too light. You normalize (Michale's term and a good one) the development in the converter to get what you desire. IF you clipped higlights you wanted to retain, you did over expose!
Quote
3. The "blinkies" are an indicator but since they rely on the jpeg and the in-camera jpeg settings, they are not a reliable indicator of clipping in the raw image.
Correct! The data is vastly different hence so is how you expose that data.
Quote
4. Someone should explain how you can have a "good histogram" using a linear tone curve and not have the optimal exposure possible given the lighting conditions. I do understand that you could purposely deviate from that exposure level to emphasize the shadow values, for example, but that is not what I mean by an optimal exposure.
I think you are putting a bit too much emphasis on histogram. I don't know what a "good histogram' should look like but I know what I want my images to look like. In my histogram video (did I leave a link?), I show how histograms do not indicate an image is good or that a histogram some would examine alone tells them the image isn't good is indicative of the actual image. The histogram in your converter gives you an idea of the data at whatever stage of the processing you're at so it's difficult to suggest you keep an eye on at all times. You do want to keep your eye on the image itself, on a well calibrated and profiled display. And again, the clipping overlays we have in Photoshop, ACR and LR, and I'm sure other products is far more indicative of the clippings affect on the actual image than the Histogram.
Title: Re: good histogram = dark images in surf pics...
Post by: leuallen on March 20, 2014, 11:37:37 am
Quote
same goes for the clever spot metering on the OM4/OM3.

Olympus still has this, at least on the EM1. You have spot (regular), spotHI (for highlights) and spotSH (for shadows). I think it is on the EM5 also.

Larry
Title: Re: good histogram = dark images in surf pics...
Post by: bjanes on March 20, 2014, 12:15:32 pm
In my histogram video (did I leave a link?), I show how histograms do not indicate an image is good or that a histogram some would examine alone tells them the image isn't good is indicative of the actual image. The histogram in your converter gives you an idea of the data at whatever stage of the processing you're at so it's difficult to suggest you keep an eye on at all times. You do want to keep your eye on the image itself, on a well calibrated and profiled display. And again, the clipping overlays we have in Photoshop, ACR and LR, and I'm sure other products is far more indicative of the clippings affect on the actual image than the Histogram.

Andrew,

Your histogram movie (http://digitaldog.net/files/Histogram_Video.mov) is excellent (as are your other recent tutorials), but on thing that you did not point out is the limitation of luminance histograms for determining clipping in the red and blue channels. This limitation is explained by Sean McHugh in his histogram tutorial (http://www.cambridgeincolour.com/tutorials/histograms2.htm). The composite RGB histogram does not keep track of the status of individual pixels, whereas the luminance histogram does as explained in the Cambridge tutorial.  Since the red and blue pixel values account for only 30% and 11% of the luminance in any given pixel, they can be 255 and the average including the green (59% of the luminance) can be well below the 255 clipping level.

Regards,

Bill
Title: Re: good histogram = dark images in surf pics...
Post by: Vladimirovich on March 20, 2014, 12:50:42 pm
3. The "blinkies" are an indicator but since they rely on the jpeg and the in-camera jpeg settings, they are not a reliable indicator of clipping in the raw image.

indeed they are not off the shelf - but in reality I can tune such indicators for both E-M1 and A7 to show raw clipping within 1/3 EV precision... granted OOC JPG becomes unusable
Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 20, 2014, 12:52:02 pm
This limitation is explained by Sean McHugh in his histogram tutorial (http://www.cambridgeincolour.com/tutorials/histograms2.htm).
Thanks Bill. That URL is actually referenced in the video.
Title: Re: good histogram = dark images in surf pics...
Post by: jjj on March 20, 2014, 12:57:16 pm
There has been massive improvement in autoexposure systems since eighties. At that time there basically were only full screen averaging, semi spot metering or fixed zones (middle, 4 segments around it, usually the top one slightly damped). Now cameras can have many variable segments with (semi) intelligent guessing about the subject, and focus point can be given extra weight in exposure calculation. I shoot 95% automatic now, if the exposure is off, I usually rather correct with exposure compensation than turn to manual. I might dial in some compensation even before starting to shoot when I know AE will not nail it.
You missed the end part of my quote off which changes the meaning enormously.
"Auto exposure is hardly likely to have improved since the 80s as the same problems will always be there, the camera cannot know what you require from a scene in exposure terms"
Not to mention that I tested my modern camera's auto exposure and it was rubbish. As the results I listed above demonstrate. But then I've never been impressed by Canon's metering full stop.
Why faff with correcting, just set the right exposure and shoot away, unless light is dodging behind clouds exposure stays pretty constant outdoors and indoors [nightclubs excluded] it's constant so unless subject in moving in an out of light sources, just set the correct exposure and shoot away.
To illustrate what I mean, the shots I took of the view from office gave me 4 different exposures with auto despite the scene's lighting not changing one iota. So to get a better result, I'd have to first decide what the correct exposure was and then adjust each reframe of composition by a different amount of exposure compensation. If shooting manually, I simply set correct exposure and shoot away, much easier as all I need to consider is the composition.
Alternatively I auto meter from where I know will give the correct exposure and recompose, rinse and repeat for every shot. Still faffier than manual.

Title: Re: good histogram = dark images in surf pics...
Post by: jjj on March 20, 2014, 02:16:32 pm
Olympus still has this, at least on the EM1. You have spot (regular), spotHI (for highlights) and spotSH (for shadows). I think it is on the EM5 also.
Not quite as multiple/averaged spot metering was also part of it, not to mention the really ergonomic buttons, whereas I think the spotHi and SpotSh are more alternate version of the spot meter mode. Not played with one long enough to even discover it had that feature, so not sure how it works, but from what I can find out, they seem to be modal which is a retrograde step.
Title: Re: good histogram = dark images in surf pics...
Post by: jjj on March 20, 2014, 02:32:41 pm
No, you just find it complicated. It's really exposure 101, you're probably not there yet. Re-read what hjulenissen wrote, it's spot on: Exactly! ETTR is the beginning of the process of producing that. What's the actual sensitivity of the sensor and the role of ISO settings? What do I have to do from what the meter recommendation (again for a JPEG or film) to produce maximum information in the raw? Simple exposure and development testing as we did when shooting film. Nothing complicated about it, it's part of photography from the day it was invented!

There is one optimal, correct, ideal exposure for any scene with of course input by the image creator (espeically if the scene's DR is wider than what the camera can capture). ETTR is simply about providing that by ignoring the incorrect meter/expsoure/development (for JPEG) seen on the camera histogram. The 'to the right' means compensate because you're under exposing the raw data by correctly exposing for the JPEG. If you have a false understanding that the two should be treated the same, you fail to understand the differences in the data, encoding, oh, I'm probably going over your head, sorry. Bottom line is, just as you would never treat a neg 'rated' at ISO 400 the same as a chrome 'rated' at ISO 100 until you tested exposure+development to produce the best results, you don't do the same with digital capture.

Now if you want to point a meter, reflective or incident and treat film, JPEG, raw, any ISO, and the development the same and expect the same results, you clearly don't understand exposure and development, again photography 101.

ETTR should just be called 'proper exposure for raw data' or whatever you want to name it. The only so called conflicting goals is being forced to under expose (and over develop, at the expense of data qualty) because you don't have enough light to fully embrace ETTR, correct exposure. In the film days we DID have to do this and we did see the result; more grain. Stopping the action or producing better data, any photographer will also understand they have to push the process, grain/noise as the net result. Lesser of two evils and again, photography 101.
The tools may be better, but the photographer who doesn't understand what they are being told and follows the advise incorrectly are not aided here. The better metering you speak of isn't going to help the raw shooter if it's based on the JPEG and they do not implement ETTR.
Wow, that's remarkably patronising. Even for you. Though your reply has very little to do with what I was actually writing about. Probably as you have quoted from three different people and attributed them all to me, all whilst being childishly insulting about my abilities to take a photograph. Yet I'm the one who does photography for a living and you do not. Funny that.

Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 20, 2014, 02:44:17 pm
Probably as you have quoted from three different people and attributed them all to me...

Actually two of three but missing such items is your specialty. Do you feel that all quotes in the body of a forum post must have individual's attributed when the entire post quoted is just below? If so, forgive me, I'll be sure to include this in the future.
Quote
...all whilst being childishly insulting about my abilities to take a photograph.
I don't see anything about your abilities to take a picture. I do see some inabilities to understand a simple process that's been done since photogrpahy was invented. Wasn't you who wrote: I think people are over complicating things here.
Quote
Yet I'm the one who does photography for a living and you do not. Funny that.
Like attempting to piss on a few images on my web page that isn't at all a photography site, this is then an attempt to dismiss the statements about exposure I wrote? Are you aware of my days of shooting for a living when perhaps you were in grade school? Any posts not made by a photographer working to make a living today is therefore easily dismissed in your mind? Such a state of mind you find funny, that's kind of a shame.
Title: Re: good histogram = dark images in surf pics...
Post by: jjj on March 20, 2014, 03:49:55 pm
Actually two of three but missing such items is your specialty.
No one was from me, two were from other posters. This is probably why you have such problems with forums, you have no idea who posted what or in what context.
Quote
Do you feel that all quotes in the body of a forum post must have individual's attributed when the entire post quoted is just below? If so, forgive me, I'll be sure to include this in the future.
Attributing quotes to the wrong person is rather obviously misleading. You shouldn't have to have that explained.
And the initial quoted post was four posts above, not just below. But hey why bother with pesky facts?

Quote
I don't see anything about your abilities to take a picture. I do see some inabilities to understand a simple process that's been done since photogrpahy was invented. Wasn't you who wrote: I think people are over complicating things here.
I did, but that doesn't mean I do not understand ETTR or other aspects of exposure. Being smart is making complex things simple and people are making a meal out of 'correct' exposure. Besides as a colleague sagely rather sagely said - the right exposure is the one the photographer deems correct. On that point I've tried ETTR and the resultant look doesn't suit my style, so do not bother with it.

Quote
Like attempting to piss on a few images on my web page that isn't at all a photography site, this is then an attempt to dismiss the statements about exposure I wrote? Are you aware of my days of shooting for a living when perhaps you were in grade school? Any posts not made by a photographer working to make a living today is therefore easily dismissed in your mind? Such a state of mind you find funny, that's kind of a shame.
Actually I've been told that you moved into colour consulting, because you weren't very good at photography or photoshop.
Oh not the ridiculous 'I'm older than you, so must know more' argument. Two problems with that a)you do not even know how old I am and b)it's bollocks anyway. Never went to grade school either.
Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 20, 2014, 04:25:15 pm
No one was from me, two were from other posters.
That's exactly correct and what I wrote! One was attributed to you. One was attributed to hjulenissen. The third, the last, my bad wasn't. Two of the three had quoted authors, you missed that too?
Quote
This is probably why you have such problems with forums, you have no idea who posted what or in what context.
Pot again calling the kettle black.
Quote
Attributing quotes to the wrong person is rather obviously misleading.
Ah, so that's how you see it. My question: Do you feel that all quotes in the body of a forum post must have individual's attributed when the entire post quoted is just below?. is at least answered without your usual ambiguity. Again I'll state: If so, forgive me, I'll be sure to include this in the future!
Meanwhile in two different forums, just this week you state you're so good at reading other's posts, an admission that doesn't hold up under scrutiny. The TIFF/PSD post is a prefect example. I wanted to move on, pointing out you missed a key part of my original writings about being done editing an image then flattening. You're still under the impression that Photoshop is a parametric image editor and that John and Julieann say as such when indeed the do not.
Quote
But hey why bother with pesky facts?
I haven't seen any facts provided by you yet. Posting quotes that don't backup what you're trying to suggest shows agreement with your opinions isn't going to fly. You are welcome to your opinions but not your own facts.
Quote
I did, but that doesn't mean I do not understand ETTR or other aspects of exposure.

This statement would suggest otherwise:
Quote
Don't like ETTR myself for example. Yes it may collect more information, but I'm a photographer not a forensic analyst, so I don't get upset by my shadows being black as that's maybe how I want them to look.  Smiley
Care to provide us a DNG with whatever settings you like, produced using correct ETTR that doesn't allow shadows as black as zero? I've never seen such a case.

Quote
Being smart is making complex things simple and people are making a meal out of 'correct' exposure. Besides as a colleague sagely rather sagely said - the right exposure is the one the photographer deems correct. On that point I've tried ETTR and the resultant look doesn't suit my style, so do not bother with it.

Look, this is a technical discussion, the subject is exposure. I know you'd rather talk about how much a working photographer you are, how much better your images are than my 'snap shots', how it's all about anything but the technical aspects of the discussion. As such, this set of discussion's isn't for you. There are proper ways to expose film, digital be it JPEG or raw or capture for HDR etc.

Quote
Actually I've been told that you moved into colour consulting, because you weren't very good at photography or photoshop.
Right, just believe whatever you want, it's immaterial to this discussion.

Quote
Oh not the ridiculous 'I'm older than you, so must know more' argument. Two problems with that a)you do not even know how old I am and b)it's bollocks anyway. Never went to grade school either.
I don't know anything about you, your lack of transparency is glaring. It doesn't matter. That you are a working photographer today and I was when you were in grade school or a nursing home dosn't matter a lick. You brought this up, the facts that you did is so telling. How does this have anything to do with helping the OP with proper exposure? It doesn't. But it gives you more troll speak to inflict on this audience.
Title: Re: good histogram = dark images in surf pics...
Post by: bjanes on March 21, 2014, 11:20:59 am
and I using LR Rawdigger can tune real time (pre shot) blinkies (E-M1) or zebra (A7) to show me when clipping starts in raw with less than 1/3 EV precision and understand what is the headroom in raw when I do spot metering.. that is I don't need clueless histogram in LR/ACR at all... that is exposure 101 nowadays.

I agree that the use of Rawdigger (or a similar program that shows the raw histogram and clipping) is the key to obtaining good exposure. It is useful to photograph a Stouffer wedge for testing, since the steps are precisely 0.3 EV apart. I photographed the wedge with the Nikon D800e using the default picture control. A near ideal luminance histogram is shown here. The highlights are just short of clipping.

(http://bjanes.smugmug.com/Photography/D800-Stouffer/i-p6MJvFr/0/L/LCD_0002-L.png)

Rawdigger shows that the highlights are about 2/3 EV below clipping. Increasing the exposure by 0.3 EV causes some clipping in the camera histogram, but the highlights as shown by Rawdigger are still slightly short of clipping.

(http://bjanes.smugmug.com/Photography/D800-Stouffer/i-Gm3qwBc/0/XL/img2-XL.png)

(http://bjanes.smugmug.com/Photography/D800-Stouffer/i-HRmbjv9/0/XL/img1-XL.png)

Increasing exposure by an additional 0.3 EV results in clipping as shown by Rawdigger. The camera histogram shows additional clipping. Using ACR with PV2010 and a linear tone curve and the exposure offset of -0.3 EV (the exposure offset used by ACR and LR) gives a fairly accurate evaluation of the raw file. PV2012 with default settings appears too bright, but step one is not clipped because of automatic highlight recovery.

(http://bjanes.smugmug.com/Photography/D800-Stouffer/i-S5CMWnV/0/XL/Img7-XL.png)

(http://bjanes.smugmug.com/Photography/D800-Stouffer/i-tkQqXGL/0/XL/07_ACR_PV2010_ExpNeg-XL.png)

(http://bjanes.smugmug.com/Photography/D800-Stouffer/i-TgqLCbZ/0/XL/07_ACR_PV2012-XL.png)

The camera histogram is highly useful if one knows how to use it. Since most histograms are somewhat conservative, slight clipping can be allowed. However, with current high performance sensors, one can still get excellent quality with highlights 2/3 EV below clipping, at least at base ISO. In difficult situations such as low light or high dynamic range subjects, one might give an additional +2/3 or 1 EV exposure in a second image. HDR bracketing would give additional insurance.

Regards,

Bill
Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 22, 2014, 12:47:33 pm
Using ACR with PV2010 and a linear tone curve and the exposure offset of -0.3 EV (the exposure offset used by ACR and LR) gives a fairly accurate evaluation of the raw file. PV2012 with default settings appears too bright, but step one is not clipped because of automatic highlight recovery.
So what's the consensus of this automatic highlight recovery? Isn't this ACR taking two good channels and building data in the 3rd? That's been the case for far longer than PV2012 I believe, but prior to PV2012, the recovery was rather ugly.
Title: Re: good histogram = dark images in surf pics...
Post by: bjanes on March 22, 2014, 05:29:10 pm
So what's the consensus of this automatic highlight recovery? Isn't this ACR taking two good channels and building data in the 3rd? That's been the case for far longer than PV2012 I believe, but prior to PV2012, the recovery was rather ugly.

Yes, that is my understanding. However, the automatic recovery with PV2012 is done without the users intervention and knowledge. I agree with Bart: it is important to know what is really going on with one's images.

Bill
Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 23, 2014, 10:58:45 am
Yes, that is my understanding. However, the automatic recovery with PV2012 is done without the users intervention and knowledge.
So again, in this case, the development plays a critical role in the total picture.
So if you get a data point about clipping with Raw Digger but you want to use PV2012 (which has lots of improvements over 2003), what do you now do? Adjust exposure or leave it based on your development preferences?
Title: Re: good histogram = dark images in surf pics...
Post by: bjanes on March 23, 2014, 11:59:41 am
So again, in this case, the development plays a critical role in the total picture.
So if you get a data point about clipping with Raw Digger but you want to use PV2012 (which has lots of improvements over 2003), what do you now do? Adjust exposure or leave it based on your development preferences?

I use PV2012 for development, but I still like to know the status of the raw file. It is not necessary to go back to PV2003--PV2010 with a linear tone curve and the proper baseline offset is sufficient for most purposes and these settings can be saved as a preset. However, ACR/LR always uses white balance, and Rawdigger is useful in difficult cases when the rendered image is clipped due to white balance and the raw channels are intact.

Bill
Title: Re: good histogram = dark images in surf pics...
Post by: ErikKaffehr on March 23, 2014, 12:03:30 pm
Hi,

I am highly skeptical about highlight recovery in any tool. Personally I don't think PV2012 does a good job, and I feel that avoiding channel clipping is a worthwhile effort.

I would wote for better histograms.

Just to say, I like Lightroom and PV2012 and it is a great product. It may even be that it does good highlight recovery, but I don't feel it is good enough for me. A real raw histogram would be nice and save a visit to RawDigger. Tools that you could trust would save a lot of time.

I would add that I am all in favour of ETTR but I think is perfectly OK to expose 1/2 stop below optimum.

Best regards
Erik





So what's the consensus of this automatic highlight recovery? Isn't this ACR taking two good channels and building data in the 3rd? That's been the case for far longer than PV2012 I believe, but prior to PV2012, the recovery was rather ugly.
Title: Re: good histogram = dark images in surf pics...
Post by: digitaldog on March 23, 2014, 01:11:27 pm
I use PV2012 for development, but I still like to know the status of the raw file. It is not necessary to go back to PV2003--PV2010 with a linear tone curve and the proper baseline offset is sufficient for most purposes and these settings can be saved as a preset. However, ACR/LR always uses white balance, and Rawdigger is useful in difficult cases when the rendered image is clipped due to white balance and the raw channels are intact.
No question that RD is a useful tool in analyzing the data prior to development which can vary. Well worth the $19.95 for the entry level offering. I'm suggesting that for the lesser color geek, gear head, it's not necessary if the goal is to expose and then develop that raw data. It would be useful to see the plots of all the control strips an E6 lab uses to control their process but it's not a requirement to nail your exposure and their development. You do need to run tests, no question. And I'd agree, while it's somewhat cool that there IS highlight recovery in ACR/LR in PV2012 that now actually works, where in the past it was quite ugly, ideally you would not clip any data in case you move to another form of development. As Erik says, it's probably much better and safer to be ½ or ⅓ stop down than ⅓ stop over even with the recovery. Testing both exposure and development as a pair should give you a very good idea how to do this and the ETTR results should be far better than exposing incorrectly for the JPEG, the crux of this discussion. Lastly, having this true, raw histogram data on the camera is would be the best solution, why after all these years of discussing ETTR don't we have one on all our camera systems?