Luminous Landscape Forum

Raw & Post Processing, Printing => Adobe Camera Raw Q&A => Topic started by: Robert Boire on December 30, 2010, 10:56:09 pm

Title: ACR Surprise when converting Canon RAW
Post by: Robert Boire on December 30, 2010, 10:56:09 pm
Hi,

I set up my Canon camera to record both the RAW and jpeg. Naturally when I view the RAW and jpeg versions in DPP (or ZoomBrowser for that matter) they look virtually identical.  However I was surprised to see that some of the RAW and jpeg look very different in ACR. Essentially the RAW version viewed in ACR is somewhat darker than the CANON jpeg. If I convert the  RAW to jpeg within ACR however, then the RAW and new jpeg are very close.

The images on the camera LCD are usually reasonably close to what I see in DPP. When I am shooting the LCD images given me a reasonable indication of whether I am managing to get the shot I want. I can then use ACR (or DPP) to fine tune the final image. So I find this somewhat difference between ACR and DPP RAW troubling since it means the RAW rendering that ACR uses provides unexpected results.

This leads to the obvious question... which RAW version/conversion is correct? And why are they so different?

Thanks
Title: Re: ACR Surprise when converting Canon RAW
Post by: Nick Rains on December 30, 2010, 11:01:40 pm
It is because your default settings in ACR bear no resemblance to DPPs initial settings which use a 'camera style' for the raw much like that of the Jpegs. If you go to the camera calibration settings in ACR you should find some options to choose a Canon-like look.
Title: Re: ACR Surprise when converting Canon RAW
Post by: Robert Boire on December 31, 2010, 11:36:11 am
Thanks.

So I went to the calibration tab in ACR as you suggested and change the camera style from Adobe standard to the same style the picture was shot with..

Yes, it was  a big change and it did shift closer to the image in DPP... However the difference is still quite significant.

Do you have other suggestions?

Thanks
Title: Re: ACR Surprise when converting Canon RAW
Post by: Slobodan Blagojevic on December 31, 2010, 12:03:35 pm
… This leads to the obvious question... which RAW version/conversion is correct? And why are they so different?...

Within the parameters you describe, there is no such thing as "correct" RAW conversion. The "correct" one is the one you like the most. Everything else is just a Canon's or Adobe's approximation/guess what you (actually, what a majority of users) might like the most. As for why they are different… for the same reason ice cream comes in hundreds of flavors: different people tend to like different things.  :)

Btw, there is no DPP conversion that can not be replicated in ACR with a little bit of tweaking. And one would argue that you could actually make a "better" conversion in ACR, given the larger number of parameters under your control.
Title: Re: ACR Surprise when converting Canon RAW
Post by: Robert Boire on December 31, 2010, 01:54:54 pm
Within the parameters you describe, there is no such thing as "correct" RAW conversion.  Everything else is just a Canon's or Adobe's approximation/guess what you (actually, what a majority of users) might like the most. 

Noted. While I recognize the subjectivity of the conversion, nevertheless I would say that if the image I see on the camera LCD screen is a reasonably close approximation of the scene itself  at the time I take the picture (or at least my faulty (and subjective) memory of the scene) and that image is reasonably close to what I see on the computer screen, then the resulting conversion is probably more accurate than some other conversion that looks completely different... or am I missing something?
Title: Re: ACR Surprise when converting Canon RAW
Post by: walter.sk on December 31, 2010, 02:14:19 pm
Noted. While I recognize the subjectivity of the conversion, nevertheless I would say that if the image I see on the camera LCD screen is a reasonably close approximation of the scene itself  at the time I take the picture (or at least my faulty (and subjective) memory of the scene) and that image is reasonably close to what I see on the computer screen, then the resulting conversion is probably more accurate than some other conversion that looks completely different... or am I missing something?

You can create a camera profile for ACR, or you could take a few representative types of image you work with and find the ACR settings that most closely resemble what you saw on the LCD or in DPP, and save the settings as an ACR default.  Or else, just use DPP for conversion and PS for post.
Title: Re: ACR Surprise when converting Canon RAW
Post by: Slobodan Blagojevic on December 31, 2010, 03:43:16 pm
… then the resulting conversion is probably more accurate than some other conversion that looks completely different... or am I missing something?

Without actually seeing what you consider "significant differences" between converters, and without knowing your camera settings (i.e., contrast, saturation, color space) at the time of shooting, I would venture to say that you are missing the following: default RAW rendering is usually duller and less appealing as the converter is trying to preserve as much dynamic range as possible. The converter can not possibly know whether you want to preserve or accentuate highlights or shadows and therefore tries to find a middle ground, i.e. a compromise. And as Henry Kissinger used to say: "compromise is a solution that leaves both parties equally unhappy"  :)
Title: Re: ACR Surprise when converting Canon RAW
Post by: Nick Rains on January 01, 2011, 03:00:13 am
Two points: the camera LCD is a really, really bad tool for assessing anything and, are you using a properly profiled monitor of high quality?
Title: Re: ACR Surprise when converting Canon RAW
Post by: Robert Boire on January 02, 2011, 12:32:58 pm
I recognize that 
the camera LCD is a really, really bad tool for assessing anything

My only point is that if a) the rendering I see on the LCD screen is a reasonable approximation to the scene itself (assuming I am looking at both at the same time and am therefore not suffering from memory lapses) and b) what I subsequently see on the monitor is a reasonable approximation to the LCD screen and c)the ACR raw rendering is not, then it seems logical that the original rendering is "more correct" (what ever that means).  Nevertheless this is getting a bit philosophical..

Yes, I am using a properly profiled monitor. Whether its "high quality" is highly debatable (its a Dell e207). But then again, I am looking at both the "good" and "bad" raw renditions on the same monitor.

Anyways thanks for the pointers.
Title: Re: ACR Surprise when converting Canon RAW
Post by: digitaldog on January 02, 2011, 02:39:42 pm
My only point is that if a) the rendering I see on the LCD screen is a reasonable approximation to the scene itself (assuming I am looking at both at the same time and am therefore not suffering from memory lapses) and b) what I subsequently see on the monitor is a reasonable approximation to the LCD screen and c)the ACR raw rendering is not, then it seems logical that the original rendering is "more correct" (what ever that means).

There is no question the camera manufacturers go to great lengths to produce an LCD preview and a JPEG most users would accept as a reasonable presentation of the scene.  But...
Considering the LCD isn’t a calibrated device, considering its not easily possible in most cases to view that LCD, the hopefully calibrated display (showing a vastly different size preview) and the scene all together, its kind of a stretch to buy into the idea they all correlate. That the LCD is a JPEG in sRGB, displayed presumably on something like an sRGB gamut LCD, that this data is rendered a fixed way with little or no option to tweak it, that visual adaptation is taking place, again, its difficult to agree its representing the scene, any more than agreeing that shooting the scene on one or more transparencies stocks match the scene. Reasonable approximation is what everyone would expect, otherwise no one would purchase the cameras and view the LCD screens (if they were way off, you’d hear most customers screaming). Is a Polaroid a reasonable representation of the film? Even if on one day you shoot Kodachrome and the next Velvia? Is the machine print you get from your color neg a reasonable representation of how you remember the scene? If it were always way off, again, customers would be screaming. In the end, its all very much like the saying “close enough for horseshoes and hand grenades”.

Title: Re: ACR Surprise when converting Canon RAW
Post by: jpassaneau on January 06, 2011, 10:11:23 am
Why not just shoot large JPG's instead of RAW. They will look just like the LCD, probably better. It's not a dumb idea. I shoot large JPG's when I'm doing happy snaps of friends and family or simple vacation photos and shoot RAW when I want the flexibility RAW to get the image I want. Note I said the "image I want" not what the in camera LCD shows which is based on camera manufacturers idea of what a JPG would look like. I'm not always trying to make it look just like I saw through the viewfinder, I want to make it look better or show I felt about the image. RAW is for people that embrace the flexibility of the mode. RAW is just that, raw and needs to be cooked before it's done and that means work for the cook.

John Passaneau
Title: Re: ACR Surprise when converting Canon RAW
Post by: digitaldog on January 06, 2011, 10:15:27 am
Why not just shoot large JPG's instead of RAW.

RAW is just that, raw and needs to be cooked before it's done and that means work for the cook.

Because sometimes the cook adds too much salt.

The basis for this excellent article:http://wwwimages.adobe.com/www.adobe.com/products/photoshop/family/prophotographer/pdfs/pscs3_renderprint.pdf
Title: Re: ACR Surprise when converting Canon RAW
Post by: Peter_DL on January 07, 2011, 05:01:20 am
Why not just shoot large JPG's instead of RAW. ...
RAW is for people that embrace the flexibility of the mode. RAW is just that, raw and needs to be cooked before it's done and that means work for the cook.

Why not just shoot Raw + Jpg in order to have both options.

 
The basis for this excellent article:http://wwwimages.adobe.com/www.adobe.com/products/photoshop/family/prophotographer/pdfs/pscs3_renderprint.pdf

Some of these articles like this one by Karl Lang are still offered in the Design Center,
whereas the former 'prophoto' website incl. white papers seems to be down (although some backuped links still seem to work).

http://www.adobe.com/designcenter/dialogbox/

Peter

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Title: Re: ACR Surprise when converting Canon RAW
Post by: Bryan Conner on January 07, 2011, 06:44:58 am
the image on your camera's lcd screen is a thumbnail produced using the same parameters as the camera jpeg shot settings are set to.  In other words, the camera is processing (guessing at what the scene should look like based on the parameters that you gave it) the raw file and creating the thumbnail.  When you open the raw file up into Adobe Camera Raw, Camera Raw is processing the raw file and creating  the full size image based on the parameters that you have specified.  If you have not changed these settings, ACR is using the settings to produce an image that is what Adobe thinks it should look like.   If you want the Camera Raw image to open as default to look like the thumbnail that you see on your camera lcd, you need to tell ACR to that.  i.e. you need to set the default settings to make the adjustments to produce that look to all of the images.
Title: Re: ACR Surprise when converting Canon RAW
Post by: Peter_DL on January 08, 2011, 05:21:14 am
If you want the Camera Raw image to open as default to look like the thumbnail that you see on your camera lcd, you need to tell ACR to that.  i.e. you need to set the default settings to make the adjustments to produce that look to all of the images.

Never reached this with one single Preset,
without intending to suggest that such mimicry would have been the final goal.

Peter

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Title: Re: ACR Surprise when converting Canon RAW
Post by: Robert Boire on January 09, 2011, 11:49:58 am
Why not just shoot Raw + Jpg in order to have both options.

In fact that is what I do, and they are reasonably similar.

This whole discussion started because the RAW rendering in ACR and DPP are very different and that DPP seems (to me) "more correct", though ACR seems more powerful.

But then as you point out, adjusting
Never reached this with one single Preset,

Title: Re: ACR Surprise when converting Canon RAW
Post by: Chris_Brown on January 09, 2011, 12:06:10 pm
This whole discussion started because the RAW rendering in ACR and DPP are very different and that DPP seems (to me) "more correct", though ACR seems more powerful.

The difference is because DPP and ACR use different camera color spaces as the starting point for rendering color. It's highly unlikely that you'll get an exact match no matter what you do.
Title: Re: ACR Surprise when converting Canon RAW
Post by: Peter_DL on January 09, 2011, 12:17:36 pm
The difference is because DPP and ACR use different camera color spaces as the starting point for rendering color. It's highly unlikely that you'll get an exact match no matter what you do.

So you know the 'camera color spaces' which are used, respectively ?

Peter

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Title: Re: ACR Surprise when converting Canon RAW
Post by: Slobodan Blagojevic on January 09, 2011, 01:47:46 pm
… This whole discussion started because the RAW rendering in ACR and DPP are very different...

I find the "very" part very surprising. I would help if you would post a screen shot of the same RAW file in DPP next to ACR, so that we can see what exactly you find "very" different. It would also help to tell us what camera parameters you are using for your jpegs (i.e., contrast, saturation, color space).
Title: Re: ACR Surprise when converting Canon RAW
Post by: Robert Boire on January 09, 2011, 07:25:40 pm
I would help if you would post a screen shot

Well I suppose I should have thought of that in the first place...It might have saved some confusion.

- CAM.JPG is the jpg saved by the camera itself
- DPP.JPG is the jpg created from the RAW by DPP
- ACR.JPG is the jpg created from the RAW by ACR
- ACR2.JPG is the jpg created from the RAW by ACR but with camera profile set to Camera Landscape instead of Adobe standard as suggested by Peter I think.

All were in sRGB. No adjustments to contrast or saturation though the Canon Picture Style "Landscape" was used.
Title: Re: ACR Surprise when converting Canon RAW
Post by: Slobodan Blagojevic on January 09, 2011, 10:23:49 pm
I would not call it "very" different, but I see what you are saying… there is a difference.

Apparently, Adobe's approximation of Canon's Landscape mode is just that, an approximation. My suspicion is that ACR default Blacks (+5) is too strong in comparison to DPP. Perhaps by moving the slider to +2 or +3 would generate a much closer rendering. I could not confirm that in LR, as jpegs have zero as a default for Blacks, i.e., I could not lower the black point of a jpeg to prove my theory.

However, I did the following adjustments in LR to the jpeg ACR2:

- Fill Light +20
- Blacks +5
- Brightness +15
- Contrast −20

Taking into account that I am doing those adjustments to a jpeg, I believe the rendering is quite close, if not identical to the camera's jpeg:


Title: Re: ACR Surprise when converting Canon RAW
Post by: Chris_Brown on January 09, 2011, 10:38:23 pm
So you know the 'camera color spaces' which are used, respectively ?

In DPP it's possible to open the app folder and find various ICC camera profiles (a lot of 'em) but which is which I haven't a clue.

As for ACR, I recall Eric Chan indicating in these forums that the program uses a combination of Adobe "camera profiles" in relation to ProPhoto to develop a color image.
Title: Re: ACR Surprise when converting Canon RAW
Post by: Alan Klein on January 10, 2011, 11:41:21 am
Can you set camera profiles in Phooshop Elements 8 to more approximate in RAW what the OOC Jpeg would look like?  That would give a good starting point.
Title: Re: ACR Surprise when converting Canon RAW
Post by: Peter_DL on January 12, 2011, 01:20:16 pm
In DPP it's possible to open the app folder and find various ICC camera profiles (a lot of 'em) but which is which I haven't a clue.

Interesting.
If there just would be a way to convert ICC profiles to DNG profiles (?),
then it could perhaps be possible to identify the right DPP ICC profile for the camera by deleting them successively from the DPP folder (test-wise),
and finally, in order to feed it - i.e. the rigth one converted to a DNG profile - into ACR/LR for comparison with the generic DNG profiles for the camera.

Peter

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Title: Re: ACR Surprise when converting Canon RAW
Post by: Schewe on January 12, 2011, 02:36:21 pm
If there just would be a way to convert ICC profiles to DNG profiles (?)

Barking up the wrong tree...ICC profiles really bare no relationship to DNG profiles. Completely different animals...
Title: Re: ACR Surprise when converting Canon RAW
Post by: Peter_DL on January 12, 2011, 04:16:05 pm
...ICC profiles really bare no relationship to DNG profiles. Completely different animals...

Oh, thanks for confirmation.

Peter

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Title: Re: ACR Surprise when converting Canon RAW
Post by: Peter_DL on January 15, 2011, 05:18:59 am
I bring my RAWs into Lightroom/ACR very flat ... Adobe Standard Profile, no TC, no sliders .. with lens correction, Daylight WB and a light default sharpening ... that's my starting point.

Starting with such 'linear' rendition as well, I sometimes tend to end too flat after all editing because my mind keeps the flat starting point for reference. So I prefer to have the option to glance at the Jpg from in-camera processing. It is not necessarily about to mimic its look, but to produce a better rendition or at least not a worse one.

Peter

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Title: Re: ACR Surprise when converting Canon RAW
Post by: wkramer on February 03, 2011, 11:44:51 am
I have a Nikon and the only way to preserve many adjustments you make in the camera when shooting raw is to use Nikon's Capture NX2 to process the raw file and then convert it to something else for PP in Photoshop.  Bringing a NEF (Nikon Raw) file into ACR results in your presets being ignored.  I don't know if Canon has its own RAW editor program that also recognizes camera presets.