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BJL

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interesting article
« Reply #100 on: April 27, 2006, 04:22:08 pm »

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Are you suggesting that DSLRs can capture a DR range equal to negative film and greater than transparencies?
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No, I am only comparing to what prints can display: traditional glossy prints can give a reflectance range of about 50:1 to 100:1, close enough to the 64:1 of 6 stops; less glossy papers give less range than that. This goes with the fact that about a 5 or 6 stops range from highlights to significant shadow detail is considered a "normal range subject", while anything more than about 6 stops requires contrast reduction at some stage to fit the "print gamut", like low contrast printing papers.

As other responses have suggested, DSLR's go comfortably beyond this 6 stop range at least at low to moderate ISO speeds: about 8 to 10 stops depending on which source you trust. Even good compact digital cameras (like the old Olympus E-10 with 5MP, 2/3" format sensor of 3.4 micron pixel pitch) have been measured as giving about 8 stops at optimum, low ISO. Slide film at least seems surpassed for DR by many digital cameras.
« Last Edit: April 27, 2006, 05:39:19 pm by BJL »
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BJL

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interesting article
« Reply #101 on: April 27, 2006, 05:38:09 pm »

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If you are metering from the midtones, you really are not exposing properly for digital ...

Also, the automated system might not be able to exclude specular highlights.

The differences in read noise at various ISOs are relatively insiginificant in most situations ...

A half stop or so of blown highlights can usually be recovered in ACR.
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I agree on everything, but maybe I have not made myself clear.
1) My whole point is that some subjects call for a different exposure settings than the CWA meter suggests: my jargon of -2, -1, 0, 1, 2 was just shorthand for "differences in exposure level from what the CW meter would say".

2) Of course, like any automated exposure system, you would at times need to change to manual mode or over-ride with a compensation setting.

3) The P. S. on my post agrees with this "in most situations" comment. I should experiment to see what borderline cases if any benefit from extra pre-amplification (higher ISO speed setting) to hold deep shadow detail that is going to be lightened in a "low contrast" print.

4) ACR saves highlights that are lost in JPEG conversion after the sensor, pre-amp and A/D convertor have handled them successfully. RAW conversion cannot save one from clipping in the pre-amp or A/D convertor (or by overflow in the sensor's electron wells themselves.)
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sgwrx

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interesting article
« Reply #102 on: April 27, 2006, 08:39:15 pm »

i've very much enjoyed this. it's opening up areas i've not considered. i've attached three photos, because of course i have to see for myself. this is with a canon 10D, all at f/4.0, times given. 50mm f/1.4 lens.  EDIT -- all shots in manual, the first two were centered on what my in-camera meter considered correct exposure.
« Last Edit: April 27, 2006, 08:40:35 pm by sgwrx »
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bjanes

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interesting article
« Reply #103 on: April 27, 2006, 08:56:20 pm »

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4) ACR saves highlights that are lost in JPEG conversion after the sensor, pre-amp and A/D convertor have handled them successfully. RAW conversion cannot save one from clipping in the pre-amp or A/D convertor (or by overflow in the sensor's electron wells themselves.)
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I'm not sure what you mean by JPEG conversion in ACR. ACR does not convert anything to JPEG but merely converts the raw file into the designated color space in Photoshop. You can then save as JPEG if you wish.

If data are clipped in the raw file, I do not think it matters where in the above sequence the clippping took place. If the channels are clipped, they are clipped and data are lost. Some cameras do allow some headroom in the raw file. ACR highlight recovery works only if one or two channels have unclipped data--it than reconstruct the clipped data using a best guess approach. This works because the channels do not usually clip simultaneously. For example, here is a picture of a color checker taken under daylight with a Nikon digital camera, converted to linear RGB with DCRaw and with no white balance applied. As you can see the channels are not balanced and the green would blow first with overexposure, and the blue and red might remain intact.
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Ray

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interesting article
« Reply #104 on: April 27, 2006, 09:54:58 pm »

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i've attached three photos, because of course i have to see for myself. this is with a canon 10D....[a href=\"index.php?act=findpost&pid=63885\"][{POST_SNAPBACK}][/a]


I believe the 10D was Canon's first camera that showed a marked reduction in noise above ISO 100 (with the same exposure). Subsequent models from the 1D2 onwards to the current 30D have taken that 'apparent' noise reduction at high ISOs (whatever the true cause) even further.
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Ray

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interesting article
« Reply #105 on: April 27, 2006, 10:34:22 pm »

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..here is a picture of a color checker taken under daylight with a Nikon digital camera, converted to linear RGB with DCRaw and with no white balance applied. As you can see the channels are not balanced and the green would blow first with overexposure, and the blue and red might remain intact.


However, in a real scene, the channel that will clip first is likely to be the one where there is the highest degree of saturation. Landscape photographers will often find that an overexposed blue sky turns cyan (after EC in ACR) indicating that more of the blue has clipped than the green (pure RGB cyan being an equal mixture of blue and green).

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I'm not sure what you mean by JPEG conversion in ACR


Bjanes, I read this comment by BJL as referring to in-camera jpeg conversion. One thing I recall about early RAW converters such as the first editions of BreezeBrowser is that they didn't do a particularly good job at recovering highlight detail. About 1/2 a stop was the most you could get, even with an overcast, predominantly grey sky. I can now get up to a whole stop in a blue sky, without serious clipping of the blue and close to 2 stops with predominantly grey areas such as a grey sky, water or grey concrete.

As you say, this might be largely due to guesswork (or better guesswork) in modern RAW converters such as ACR and C1.
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Ray

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interesting article
« Reply #106 on: April 28, 2006, 12:18:01 am »

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No, I am only comparing to what prints can display: traditional glossy prints can give a reflectance range of about 50:1 to 100:1, close enough to the 64:1 of 6 stops; less glossy papers give less range than that. This goes with the fact that about a 5 or 6 stops range from highlights to significant shadow detail is considered a "normal range subject", while anything more than about 6 stops requires contrast reduction at some stage to fit the "print gamut", like low contrast printing papers.


BJL,
Whilst that is broadly true, the dynamic range issue for me is mostly about the quality of the shadows, not the fact that one might be able to faintly discern some degree of very degraded detail in the lower 3 stops of a claimed 10 stop or 8 stop DR. In the brightest parts of the image, quality is excellent till it quite suddenly disintegrates. However, in the darker parts of the image, quality just gets progressively worse, slowly descending into a total mess which is best rendered as total black on the print.

There's an implication in your above statement (although perhaps I've misread it) that we shouldn't be too concerned about the DR limitation of modern DSLRs because the reflectance DR of glossy prints is only 5 or 6 stops and therefore any digital image with a greater than 6 stop DR has to be compressed, using the wet darkroom analogy of a low contrast paper.

The eye, as it flits around, surveying a scene, is like a camera that could take multiple shots at different apertures. Unfortunately, current cameras can use only one aperture at a time to capture a scene. Multiple shots for blending purposes require a tripod and a static subject. There are many occasions when I feel the need for multiple exposures to improve DR but simply don't have a tripod. A program that could perfectly align the slight misregistration of hand-held bracketed shots would be very useful. Maybe one one already exists?
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BJL

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interesting article
« Reply #107 on: April 28, 2006, 04:43:26 pm »

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There's an implication in your above statement (although perhaps I've misread it) that we shouldn't be too concerned about the DR limitation of modern DSLRs because the reflectance DR of glossy prints is only 5 or 6 stops and therefore any digital image with a greater than 6 stop DR has to be compressed, using the wet darkroom analogy of a low contrast paper.
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Not quite; of course I agree that some scenes need more than an 8 stop DR.

All I am saying is that the 8-stops and more of every current DSLR at low to moderate ISO speeds is comfortably enough for scenes of low to normal subject brightness range, which are a large proportion of the total. That is, enough for scenes that are suited by "straight prints", made with no low contrast processing like pushing up of the tone curve in the shadows. Have you experienced visible noise problems in straight prints from the lower ISO settings of a DSLR? I haven't, even with my E-1, a camera much accused of having "too much noise".
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bjanes

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interesting article
« Reply #108 on: April 28, 2006, 07:21:11 pm »

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However, in a real scene, the channel that will clip first is likely to be the one where there is the highest degree of saturation. Landscape photographers will often find that an overexposed blue sky turns cyan (after EC in ACR) indicating that more of the blue has clipped than the green (pure RGB cyan being an equal mixture of blue and green).

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It takes quite a bit of overexposure to blow out blue sky, since neither the luminance nor saturation of clear blue sky is that high. Much more likely, is blowing out of the clouds in a blue sky as shown in the shot of the Golden Gate Bridge in Bruce Fraser's article. With the histogram in ACR it is easy to see which channels are blown. In my experience with ACR and my shooting, the blown channels most often show as white in the histogram, as in Bruce's example, indicating all three channels are blown in the white balanced image. Your mileage may vary, but the essential point is that highlight recovery requires data in at least one channel.

[a href=\"http://www.macworld.com/2005/03/secrets/marcreate/index.php]http://www.macworld.com/2005/03/secrets/marcreate/index.php[/url]

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Bjanes, I read this comment by BJL as referring to in-camera jpeg conversion. One thing I recall about early RAW converters such as the first editions of BreezeBrowser is that they didn't do a particularly good job at recovering highlight detail. About 1/2 a stop was the most you could get, even with an overcast, predominantly grey sky. I can now get up to a whole stop in a blue sky, without serious clipping of the blue and close to 2 stops with predominantly grey areas such as a grey sky, water or grey concrete.
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Again, bolstering my point about the sky blowing highlights and reinforcing my point about white balance multipliers in the color channels. However, I still do not see how JPEG is related to highlight recovery in RAW. Moreover, highlight recovery does not work with JPEG.
« Last Edit: April 28, 2006, 07:26:03 pm by bjanes »
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RichardChang

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interesting article
« Reply #109 on: April 28, 2006, 08:04:06 pm »

Since so many are chiming in with their opinions on this topic, it is perhaps practical to add mine.  I think that Rags has the right idea but I also think the placement of highest important value should be relative to the number of tones the output target can support.  A zone V placement may or may not be appropriate for some papers and the scene's range should be kept in mind.

The goal in digital photography as I see it, is to distill from the total number of tones our capture device records, the correct number of tones for the target we've chosen. This correct number of tones needs to have a progression that illustrates the emotion the shooter wants to imbue his image with.  This means the total contrast has to be correct and the local contrast has to be correct.  Perhaps the best conductor of tones we've ever seen is Ansel Adams.  Would Ansel make a grade 1 neg for grade 5 paper?  Not likely, at least as far as physics is concerned.  A grade 1 neg has way more tones than grade 5 paper can render.  Consider that the expose right crowd is making a grade 1 "neg"/file for every scene and every target.  The mantra is "get all the data".  When faced with the idea that you will never be able to render all these tones on some reflective targets, what's the point?  Why not capture the number of tones that you want?

This capturing of tones is problematic, when faced with a histogram for a report of where the highest important tone to you, resides within that histogram.  Good luck finding it in the data stacks.  The reality of the histogram suggests you cannot place an important value; all you can do is make sure you don't saturate the image, so that's the ritual.  Give the scene as much exposure as you can, and head for Photoshop.

Rags' contention that less exposure may be better has it's roots in manufacturing a specific number of tones for a picture rendering.  While zone V is drastic for some scenes and targets, it's not all that unbelievable for some capture devices.  Why?  Let's compare the number of tones in 12 bits (4096) with the signal-to-noise ratio of a high end camera back (4000:1).  We've got approximately 4000 units in each comparative and the equation suggests that the noise in 12 bits is approximately 1 bit.  In 12 stops of range, zone I has noise (0 is black) and the others are noise free.

For a normal scene (for example, let's say it's a 6 stop scene), one could expose right, place the highest important value way high with the histogram and no zone in the scene has noise.  One could also expose the highest important on zone VII, and no zone in the scene has noise.

Editing these two pictures will be different.  If the highlight needs contrast, you're stuck with Photoshop's special features like Hightlight & Shadow; since you can't increase highlight contrast without depressing the curve below the highest important value-- there's no room to map the high value upward with more contrast.  Depressing the curve depresses tones while it adds contrast below the highest important value, and it flattens the shadow.  If you're thinking that here's a great way to sell a software feature like Highlight & Shadow, you're right.  Of course there's always the layer masking, selection based, high bit, gotta have a $2,000 monitor, post production gymnastics that the expose-to-the-right crowd is proposing, but does that fit the regular Joe's budget?  If it does, you may be a proponent of expose-to-the-right.

If we look at the zone VII exposed highest important value, there's flexibility in mapping this placed value upward to the print target's highlight.  You can add contrast, or you can smoothen the adjacent values; it's your choice.  And, all the tones below are stretched in proper context, appropriately emotional, with the resultant tonality quite filmlike and unlike the overprocessed, artifical, and invasive edits common today.  With many shooters, more edits, layers, masks, and complexity equates to a better picture.  I don't agree, I'd still rather see one of Ansel's best, compared to the modern digital ethic's "best".  A trip through several of today's modern photo rags will illustrate my point on overprocessed imagry.  Very little of it looks real.

If you don't possess a 4000:1 capture device, you may be relegated to "expose to the right". If you have one of these better performing devices, do some testing and see if you like the result.  The pictures will look different, only you can decide if you like the result.

We're early on in the digital photography evolution, we've been at it for only 20 years.  At first we didn't have enough tones.  Now, we have more than we can print.  Between these ethics, we've struggled for more tonalty and now that we have it, we've become complacent by ritualizing the sending of too many tones.  As we progress, it's practical that we'll all discover that the true craft of all this technology in making truly emotive images, is best acheived by making the right number of tones for what you want to visually say.

Richard Chang
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bjanes

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interesting article
« Reply #110 on: April 28, 2006, 09:33:31 pm »

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Would Ansel make a grade 1 neg for grade 5 paper?  Not likely, at least as far as physics is concerned.  A grade 1 neg has way more tones than grade 5 paper can render.  Consider that the expose right crowd is making a grade 1 "neg"/file for every scene and every target.  The mantra is "get all the data".  When faced with the idea that you will never be able to render all these tones on some reflective targets, what's the point?  Why not capture the number of tones that you want?

For a normal scene (for example, let's say it's a 6 stop scene), one could expose right, place the highest important value way high with the histogram and no zone in the scene has noise.  One could also expose the highest important on zone VII, and no zone in the scene has noise.

Editing these two pictures will be different.  If the highlight needs contrast, you're stuck with Photoshop's special features like Hightlight & Shadow; since you can't increase highlight contrast without depressing the curve below the highest important value-- there's no room to map the high value upward with more contrast.  ?  If it does, you may be a proponent of expose-to-the-right.

Richard Chang
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Richard,

A thoughtful post, but I don't think your analogy to Adam's zone methods is quite correct. If the dynamic range of the subject is equal to that of the film or sensor, one  has no exposure lattitude. With digital you should place the highlights just short of clipping--any less exposure and the shadows will be clipped. With negative film, you should place the shadows requiring tonal texture on Zone II. The highlights with texture will then fall on Zone IX.

With a short scale subject where the dynamic range of the scene is less than that of the sensor or film, you have some lattitude in placement. With film, you can place the shadows higher than with the full scale subject, and the highlights will still be on the linear portion of the characteristic curve. You might place the shadows at Zone III for additional detail, but further additional exposure increases grain, decreases acutance and is not recommended by Adams. Depending on your visualization, you might also consider expansion for the short scale subject.

With digital and a short scale subject, it is best to place the highlights just short of clipping so as to maximize the number of tones and signal to noise ratio. If you expose Zone VII at Zone X, you then use -3 EV compensation in ACR. The contrast does not change.

Of course digital response is linear whereas film is log and digital lacks the knee and shoulder of film and clips abruptly. When gamma correction is applied to digital, the resulting curve then resembles the characteristic (H&D) curve of film.
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Schewe

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interesting article
« Reply #111 on: April 28, 2006, 10:10:51 pm »

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The mantra is "get all the data".  When faced with the idea that you will never be able to render all these tones on some reflective targets, what's the point?  Why not capture the number of tones that you want?
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Simply because then you are locked into the scene interpretation you made when capturing and reduce the flexibility to reinterpret with post processing.

And while you may think post processing is less desirable, I would argue that an artist will do whatever it takes to get the image to look the way they want.

You choose to talk about Ansel Adams. Do you know how he worked? Do you realize that he would develop by inspection back when the films he used were orthochromatic? He would use N+ and N- processing to control the exact density range of his negs. Do you honestly think he printed in the darkroom without doing things like dodge/burn, hot processing, local finger agitation?

No, those were the tools of the day. Those techniques were his post-processing, his Photoshop. The "Zone System" has progressed far afield from the limitations Adams faced in his darkroom.

There is nothing particularly nobel about engaging in photography without post-processing. It's an arrogance some engage in, while others see the end results as what is important. True, depending on your intention, it can be less than honest if you engage in deceptive alterations outside of the context of the intent-such as journalism or documentation. I'm not limited by those restrictions.

A print hanging on a gallery wall doesn't tell the viewer how it's been modified by some post-processing, not if you know what you're doing. A print just shows what the artist deems important. The viewer really has no further knowledge about how the image was made. As it should be.

You all are free to do whatever the heck strikes your fancy, but if you follow Rag's advice and expose for Zone V, you are wasting opportunity, reducing flexibility, locking in the scene interpretation and do not really have a grasp of the process and the craft that is digital capture.
« Last Edit: April 28, 2006, 10:13:32 pm by Schewe »
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Mark D Segal

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interesting article
« Reply #112 on: April 28, 2006, 10:37:12 pm »

I don't see much point agonizing over the zone system when doing digital photography. We'll get the best results we can using the technology the way it should be used, and the way it should be used depends on its technical characteristics. If we can end-up with less noisy appearance and smoother gradations by exposing to the right and then deriving the luminosity we want using curves and layer-masking so be it - that's the way to go.
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Mark D Segal (formerly MarkDS)
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Jonathan Wienke

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interesting article
« Reply #113 on: April 28, 2006, 11:37:01 pm »

I've shot in excess of 100,000 frames with DSLRs (Canon 1Ds, 1D-MkII, and 10D), and about 10,000 frames with P&S digitals, and I have yet to find a subject that materially benefits from placing important highlights (those that need detail for the image to "work") more than a half stop below clipping. As long as no important highlights are clipped, increasing exposure always improves noise levels and shadow detail, resulting in a RAW file that offers the greatest flexibility in processing. If a dark "look" to the image is desired, exposing to the right and converting the RAW with a negative exposure setting can deliver an image with identical tonality to one given less exposure, but the image with greater exposure will be much cleaner and will require significantly LESS post-processing than the frame with less exposure.
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Ray

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interesting article
« Reply #114 on: April 29, 2006, 02:15:41 am »

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Have you experienced visible noise problems in straight prints from the lower ISO settings of a DSLR? I haven't, even with my E-1, a camera much accused of having "too much noise".
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BJL,
Yes I have. It's probably a consequence of living in a sunny clime where brightness levels are greater than in northern Europe. Current DSLRs are inadequate for many rainforest shots as well as sunset shots in general.

We should bear in mind that 'artists' (a phrase I'm not inclined to use, "Woohee! I am an artiste ") will strive to make use of the limitations of the medium to the best advantage. This might include using generally obnoxious grain in film to create an effect of austerity, or whatever. It might include using the camera's limited dynamic range to reduce distracting detail and induce an aura of mystery through the creation of black shadows. Michael R is very good at this. His recent shots from Nambia emphasise form and contrast to great effect.

The resulting tradition of how great photographers have handled these limitations results in a style to be imitated by less experienced newbies; the portrait with one side of the face in deep shadow, for example.

We get used to seeing such examples as the pinnacle of photographic achievement, perhaps not realising that they were essentially an 'artistically' successful reaction to the limitations of the medium.

But supposing we want the camera to produce what the eye sees? For some people, that is a given. But the more sophisticated of us realise that it's not a given. There are many instances when the camera simply fails to deliver what the eye sees. Dynamic range limitations of the camera are one of them.

I'm going to illustrate this point with a few shots of a sunset which are not particularly great shots but were taken shortly after I discovered that my newly purchased 24-104 IS Canon lens had a flare problem. I set about searching for this problem. I didn't find it, but the following shots are part of the result of my efforts to find it.

The first shot below is a straight conversion with shadows at zero, EC at minus 1 stop, contrast at -50 and luminous and color NR at maximum. I left brightness at default 50 so you could see the thing. Here it is.

[attachment=519:attachment]

I'm sure you will all appreciated that this image is definitely not what the eye sees. It needs working on. The tree on the left is a distraction. Let's crop it out. The foreground needs lightening (for what the eye sees). I know it was never that dark when I took the shot.

Here's the reult.

[attachment=520:attachment]

Now here we're into endless artisitic discussions about appropriate levels of brightness. I'm going to cut through that and deliver a crop of part of the image which 'approximates' what I saw when I took the shot. As you can see, it's a very degraded image.

[attachment=521:attachment]

ps. I should add a couple of points which I forgot to mention in the original post. Minus 1 EC was in relation to a Prophoto color sapce. ARGB would have necessitated a -2 EC correction in ACR to reduce the spike at the right side of the histogram.

The final shot is only a poor approximation of what I saw.
« Last Edit: April 29, 2006, 02:52:37 am by Ray »
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RichardChang

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interesting article
« Reply #115 on: April 29, 2006, 04:32:49 am »

With regard to the comments by Jeff Schewe:

Why not capture the number of tones you want?

> Simply because then you are locked into the scene interpretation you made when capturing and reduce the flexibility to reinterpret with post processing.

Why is it you think I need to reinterpret?  Why can't I decide exactly how I want my image to render, on the target I choose?  Why can't I decide how to render my vision?  Why to I have to make the compromise exposure for what I want, simply to allow a reinterpretation that I'm not interested in?

>And while you may think post processing is less desirable, I would argue that an artist will do whatever it takes to get the image to look the way they want.

I never said that post processing is less desireable, I suggested that I don't appreciate the over processed look of some of the expose-to-the-right imagery.  I do post processing, layer adusts, masks and the like.  I even did the Schewe edge sharpen routine until the new Photoshop sharpening showed up.

>You choose to talk about Ansel Adams. Do you know how he worked? Do you realize that he would develop by inspection back when the films he used were orthochromatic?

I do know how he worked and I did development by inspection in the early 70's too.  I'll defy you to accurately see the proper total development of a finely detailed reflectance on a neg, in the low level safe lighting that Ansel inspected in.  It's not like checking the densitometer in Photoshop.  How Ansel's early development transpired is taking my point on a tangent and it's not relevant to my opinion.  Perhaps you can comment on some of Ansel's Polaroid P/N 55 imagery from Yosemite in the winter, what kind of tangent can you present here?  Ansel gave up on inspection development as soon materials got consistent.  Are you trying to suggest that the Tri-x and HC110 development table of times many of us used were articulated by Ansel with inspection development?  Ansel's images from the later portfolios didn't involve inspection nor did they need it.  To characterize Ansel's work as inspection development work is a stretch to me.

>Do you honestly think he printed in the darkroom without doing things like dodge/burn, hot processing, local finger agitation?

Of course not: I own The Print (in fact, I own the whole series).  I know about flagging contact printers, printing with  KodakAzo and Agfa Contactone,  jiggle machines, Codelights, metronomes, DeBeers formulas, and all the other stuff he wrote about.  

>There is nothing particularly nobel about engaging in photography without post-processing. It's an arrogance some engage in, while others see the end results as what is important.

I agree that there is nothing noble about eschewing post processing.  I also agree that it's an arrogance that some engage in.  And I do belive that what the audience sees is what is important, which is why I don't expose-to-the-right.  I choose to handle the scenes I shoot, differently.  And I choose to not have to take the image editing path that is recommended (and is sometimes required) by the expose-to-the-right crowd.

>A print hanging on a gallery wall doesn't tell the viewer how it's been modified by some post-processing, not if you know what you're doing. A print just shows what the artist deems important. The viewer really has no further knowledge about how the image was made. As it should be.

Amen to that; we agree.  I know you'll do what you espouse and I know I'll do what what strikes my fancy.  I don't want my pictures to look like yours, any more than you want your pictures to look like mine.  We both think we know what we're doing, and that's fine by both of us.

>You all are free to do whatever the heck strikes your fancy, but if you follow Rag's advice and expose for Zone V, you are wasting opportunity, reducing flexibility, locking in the scene interpretation...

I will do what strikes my fancy.  Rag's advice to expose for Zone V won't work for every scene and I don't agree that one should.  But less than expose-to-the-right works best for me on a number of levels.  My choosing to lock scene interpretation is deeply rooted in Ansel's teaching; it worked for me when I shot film and I embrace it with digital.  I don't want flexibility, I want the best rendering for my previsualization and I want to lock in my scene interpretation for my chosen target.

>...and do not really have a grasp of the process and the craft that is digital capture.

As a technical representative of a camera back maker (MegaVision, Inc.) going back 10 years,  I'll believe that I know a fair amount about the process and the craft that is digital capture.  Besides working for MegaVision, I've run imagesetters and made film based proofs on DuPont, Kodak, and Fuji proofing systems with the film.  I used color management with Efi's Cachet prior to the notion of device independent color.  I've been around this digital capture business since 1992 and I've used Ansel's concepts to teach digital on 6 continents.

When I first heard you at a trade show, you were telling everyone that digital capture wasn't good enough and that film and scanning was the only way to go.  Digital tonality and the way we handle tones hasn't really changed since then, but we do have new Photoshop tools and we now have your notions of what process and craft are all about.  

In the old days of film, some guys could shoot Agfa, some could shoot Minoltas, and some could shoot Cambos and Speedos, even though they weren't mainstream.  All that counted was the picture.  We ought to hold our image making to the same standards; what the picture looks like should be what's important.

Richard Chang
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Schewe

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interesting article
« Reply #116 on: April 29, 2006, 01:42:47 pm »

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Why is it you think I need to reinterpret?  Why can't I decide exactly how I want my image to render, on the target I choose?  Why can't I decide how to render my vision?  Why to I have to make the compromise exposure for what I want, simply to allow a reinterpretation that I'm not interested in?

Well, I for one would not want to be locked into a target in the field. How are you evaluating the resulting capture in the field? I certainly hope your determination isn't based on the camera's LCD, ala "chimping" and a histogram only tells you the image stats, not what the heck it looks like...me? I wait until I get back to the studio and use a well profiled display to make the final determination of what the image SHOULD look like...and I'll be the first to admit that upon first seeing an image on my display, I may just want to change it-heck, I'll almost ALWAYS want to change it!

As long as I've achieved the maximum usable data capture I have that flexibility to interpet the scene any way I want in post. That is indeed what the whole digital revolution is all about for me, absolute total control over the final printed image. So, why would I want to limit what I can do with an image right at the very start of the process-at the point of capture. It's the primary reason I shoot raw instead of jpg. Your way of limiting data capture at the point of exposure is akin to shooting jpg. You bake a tone curve in at capture? I don't think so...at least not for me.

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To characterize Ansel's work as inspection development work is a stretch to me.

I didn't, but you may have taken it that way-which is wrong. I specifically said he developed by inspection when shooting orthochromatic films...he gave up instpection development when he switched to panchromatic films. Safelights for panchromatic films are not really useful for anything other than seeing a very dim spot in space. :~)


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When I first heard you at a trade show, you were telling everyone that digital capture wasn't good enough and that film and scanning was the only way to go.  Digital tonality and the way we handle tones hasn't really changed since then, but we do have new Photoshop tools and we now have your notions of what process and craft are all about.

Pretty sure that was in the early 90's, right? And digital capture back then -WAS- so limiting that film was still far superior to digital capture. A lot has changed in 10 years don't you think Richard?

The first digital capture I did was with a Megavision back (or was it a Carnival back?) that I rented in 1996. I was able to turn the job around-the final halftone reproduction of 4x5 @ 150LPI in an incredably short time (the reason we went with digital). I think it was a 2K capture which with cropping was just good enough.

When Canon came out with the 1Ds I did an article for PEI magazine which proved to me that with the exact same lens, comparing 35mm film and 11MP capture, the digital capture out resolved the film, had better dynamic range and better color. That was the last time I really ever shot film with the exception of certain large format stuff that needed extensive camera movements.

I wasn't sure it was you Richard, when you first posted...glad to see you're still around! Now please tell me you haven't drank Rag's Cool-Aid, ok?

:~)
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RichardChang

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interesting article
« Reply #117 on: April 29, 2006, 03:56:40 pm »

Quote from: Schewe,Apr 29 2006, 05:42 PM
Well, I for one would not want to be locked into a target in the field. How are you evaluating the resulting capture in the field? I certainly hope your determination isn't based on the camera's LCD, ala "chimping" and a histogram only tells you the image stats, not what the heck it looks like...

Actually, I'm using an OQO computer running MegaVision's Photoshoot 4 capture software.  I load a paper target into our Color Coded Light Meter (fancy term for gamut alarm meter) which illustrates in colors, those scene pixels that constitute the renderable endpoints of my paper-- red is blown and yellow is a just-separable high.  Dark blue is plugged on the chosen paper and light blue represents the lowest separable values.  Other colors denote 3/4, midtone, and quarter-tone.  There's a histogram but it's clearly inferior to Color Coded Light Metering.  The OQO also runs CS2, so I have that as well if I want to check anything on the spot.  It all fits on the back of my camera-- http://www.mega-vision.com/products/1shot/1shot.htm.  The display is 3.5 x 5 inches and it can easily be seen in direct sunlight.

>As long as I've achieved the maximum usable data capture I have that flexibility to interpet the scene any way I want in post. That is indeed what the whole digital revolution is all about for me, absolute total control over the final printed image.

For many workflows, that's a fine approach.  Ansel taught me to make a decision about what I saw (previsualization) and take whatever steps were necessary to acheive that previsualization.  This style isn't what you're doing, but it isn't broken either-- it's just a different style.

>So, why would I want to limit what I can do with an image right at the very start of the process-at the point of capture.

Because you've decided exactly what you want to do?  According to your text, that doesn't happen and you decide later.   I don't suffer that lag in decision making.

What you do decide to do, is directed by the look of the monitor, the eventual success of your edits, and your remberance of the scene, which may be recent or it may not be recent.  Why wouldn't I want to encode my vision behind the camera, into my picture?  Why do I have to wait till I get to a calibrated display to make decisions?  Your workflow works for you but it isn't spontaneous, at least not in a traditional photographic sense.  It sounds like more of a reaction to what you end up with back at the studio.

Of course we all bracket our exposures, it would be infantile not to.  Which brackets do I end up using most of the time?-- the one that has caused me to express my opinion to this thread.

>It's the primary reason I shoot raw instead of jpg. Your way of limiting data capture at the point of exposure is akin to shooting jpg. You bake a tone curve in at capture? I don't think so...at least not for me.

I don't shoot jpg.  MegaVision instituted RAW capture in 1996 with our then named MEGA file.  We don't bake in a tone curve either, we're always shooting raw but you get to see the development intention in Photoshoot, expressed in tenths of a stop for push and pull, and tenths of a logarithmic density value in our DR. Change the intention and see the result on the paper with the Color Coded Light Meter.  Shooting the picture saves the raw (our raws are .dng's) to disk; you can use our developing or go to ACR.

Luminance and chromnance are handled separately in Photoshoot, we don't remap ratios of RGB.  And we're fully savvy with regard to ICC profiles, working spaces, and rendering intents.  We also have IPTC, Metadata, and searchable keyword databasing in Photoshoot.


Regarding Ansel's inspection development:

> I specifically said he developed by inspection when shooting orthochromatic films...he gave up instpection development when he switched to panchromatic films.

If you check my previous commentary on this, you'll see I agree.  I'll believe that he made way more pictures with panchomatic emulsions than he did with ortho's.  My comments tried to address that Ansel didn't do a lot of development by inspection and that he dropped it like a hot rock when panchromatic emulsions came about.  I'll also offer that with the panchromatic emulsions, the zone system became more difficult because the film had much better contrast (it became a relatively modern emulsion as we know it), and Ansel used it to shoot images like Mt. Williamson, the Grand Tetons, and Mt. McKinley.  Ansel's best tonal renderings weren't made with ortho films.  My comments about Ansel were directed to this imagery-- I didn't mention development by inspection because I don't think it has merit today.

>Safelights for panchromatic films are not really useful for anything other than seeing a very dim spot in space. :~)

I think I mentioned something to that effect.

Meeting up the first time:

>Pretty sure that was in the early 90's, right? And digital capture back then -WAS- so limiting that film was still far superior to digital capture. A lot has changed in 10 years don't you think Richard?

Yes, it was early on when you talked on a panel regarding copyright-- possibly at the Javits.

Far superior is relative, and although a lot has changed, some things haven't.  In the early days of digital, we were restricted to smaller image areas and smaller target renderings.  When we shot for catalog illustrations (less than full page) we had just adequate resolution with a 4 megapixel 3 pass.  Photoshop was amazing then too.  Yes we had to light carefully, but we could manage tones as well then as we can now-- it was a narrower envelope then but the picture rendering was as good as it is now, at least in process color on press.  I do like today's extra resolution and improved signal-to-noise, and the ability to have the computer on the back of my camera gives me capability I didn't have then.

>I wasn't sure it was you Richard, when you first posted...glad to see you're still around! Now please tell me you haven't drank Rag's Cool-Aid, ok?

I am still around.  And no, I haven't drunk Rag's Cool Aid, but I will say that I've given less exposure to my work; based on the target, the scene contrast, and how I want to render the scene.  Yes I have a cutting edge s/n ratio in my E5 back which allows me this luxury, and I do expose-to-the-right with my Canon Powershot.  I take the path my equipment allows me to take.

I can see that you're still as feisty as always, keep it up!  MegaVision is doing Photokina and Photoplus at the Javits this year; if you're around, stop in and see us.

Richard Chang
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Chris_T

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interesting article
« Reply #118 on: April 30, 2006, 07:32:17 am »

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I agree entirely. I don't think Ansel Adams would have any trouble exposing for digital. He would merely place Zone X at the highest DN of the raw file. In his later books, he recommended against using an averaging meter, but used a 1 degree spot meter to determine dynamic range and place the tones properly. Similarly, chrome users are accustomed to exposing for the highlights.
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What we need is a book or tutorial titled "Digital Cameras for Experienced Film Photographers", which focuses on how digital DR, metering, noise, ISO, etc. differ from film, and how certain photo techniques remain unchanged from shooting film to digital.
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Chris_T

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interesting article
« Reply #119 on: April 30, 2006, 07:35:22 am »

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No, I am only comparing to what prints can display: traditional glossy prints can give a reflectance range of about 50:1 to 100:1, close enough to the 64:1 of 6 stops; less glossy papers give less range than that. This goes with the fact that about a 5 or 6 stops range from highlights to significant shadow detail is considered a "normal range subject", while anything more than about 6 stops requires contrast reduction at some stage to fit the "print gamut", like low contrast printing papers.

As other responses have suggested, DSLR's go comfortably beyond this 6 stop range at least at low to moderate ISO speeds: about 8 to 10 stops depending on which source you trust. Even good compact digital cameras (like the old Olympus E-10 with 5MP, 2/3" format sensor of 3.4 micron pixel pitch) have been measured as giving about 8 stops at optimum, low ISO. Slide film at least seems surpassed for DR by many digital cameras.
[a href=\"index.php?act=findpost&pid=63869\"][{POST_SNAPBACK}][/a]

Thank you and others for commenting on digital DR. All your posts seem to say that digital DR is a function of ISO and noise. That's a relationship not apparent on film.
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