Problems with color when importing a .dng into photoshop cs3 - page 2 - RAW Shooting and Processing - CHDK Forum

Problems with color when importing a .dng into photoshop cs3

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Offline zosX

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Re: Problems with color when importing a .dng into photoshop cs3
« Reply #10 on: 07 / February / 2009, 18:36:17 »
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What do you mean that the color matrix for dng4ps2 is better than CHDK? The white balance is still pretty off. The cup is actually white when it is correct. Also as a result of the -50 saturation the color saturation is affected in a pretty negative way. I'm convinced that picasa is importing it correctly as it closely matches the jpegs colorwise. Doesn't picasa use dcraw code for raw converstion? It seems that photoshop just doesn't like the 10 bits or something. Raw Therapee will open the file but will only save as a jpeg or tiff. Its demosaic patterns do weird things to the noise in the RAW too...... Is there anything that is lost in the conversion to tiff? Honestly I would just much rather keep as much of it RAW as I can.......

Am I to understand that other A series import ok into photoshop?

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Offline zosX

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Re: Problems with color when importing a .dng into photoshop cs3
« Reply #11 on: 07 / February / 2009, 21:01:51 »
Ok. After much experimentation, I have discoved that the best way to get the RAW to something that photoshop will import and keep (mostly) original colors. First of all, dng4ps2 works if you save as crw and let it combine the jpeg information with the crw. The resulting dngs open ok in photoshop, though I don't like how the demosaic makes a discernible pattern close up.  The image looks smoother zoomed in in picasa, but I am guessing that picasa does some image smoothing techniques anyways because it uses dcraw for raw conversion and applying the same files through dcraw gives the same mosaic effect as photoshop. Its a minor nitpick though. CS3 has some pretty nice controls for importing raw and allows you to fine tune the noise levels, etc. So anything that uses dcraw will deal with the dng and you can convert it to tif or whatever. If you want to import into photoshop directly, it seems that saving in .crw and running it through dng4ps2 will work and give good color results. I don't know what happened with your example above but I got good results on my end and yeah, the color matrix in dng4ps2 seems pretty good with good color representation.  Maybe something happened in the process of stripping out the dng because the example you gave above didn't look so hot. It should be noted perhaps that dng4ps2 adds exposure information (it seems at least) and the resulting pictures look darker in picassa than photoshop, but I could care less about that personally since anything I share on the web is in jpg format anyways. Oh on a side note. You can convert in picasa if you "SAVE AS" and then type tif as the extension. I've found the image quality with TIFF to be somewhat lower in the conversion for some reason. I don't know if it is the way the TIF is compressed and saved, but it certainly is not pixel pefect.

One question here though. What happens to the bad pixel feature? If you save as crw...you don't get the bad pixel subtraction, am I correct? What about the dark frame subtraction? Doesn't that do the same thing?
« Last Edit: 07 / February / 2009, 22:14:24 by zosX »

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Offline zosX

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Re: Problems with color when importing a .dng into photoshop cs3
« Reply #12 on: 07 / February / 2009, 22:21:02 »
So I go and make some test pictures with crws and dngs because I am BOUND and DETERMINED to get to the bottom of this and low and behold guess what happens? DNGs suddenly import without color issue into photshop! How this happens I have no idea. Perhaps I had something set differently when I took those shots before? I have no idea whatsoever. Anyways the colors look really pretty faithful and it adheres to even custom white balances. I honestly don't know what to say. I'm going to play with this stuff for a while and try to come up with the best results I can and I'll post a reply with whatever else I might have found.

PS: I should add that I *did* change the option for Bad Pixel Removal to RAWConv. It was set to average before. I don't know if that would have really affected the resulting dng files that much, and I do not know exactly what this mystery feature does.
« Last Edit: 07 / February / 2009, 22:28:27 by zosX »

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Offline vit40

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Re: Problems with color when importing a .dng into photoshop cs3
« Reply #13 on: 08 / February / 2009, 03:04:04 »
I took a brief look into 1652.dng. Color matrix doesn't look right to me, so you can't expect good colors. Especially position of red primary - it's (1.57, 0.05) in CIExy diagram, which is WAY OFF. Usual values for small sensors are somewheree around (0.7,0.3). Greeen seems to be somewhere near expected position (although y position probably to high = green oversaturated), blue also doesn't look too good, its moved too far to magenta from my opinion

Zosx, your "it works" example also doesn't look good. Color temperature above 10000k and high tint value - that's far from expected values for a photography taken with a flesh. It should be around 6000K and tint near zero (although I suppose WB from Canon cameras usualy have higher color temperature, about 7000K or so, to give a warmer look, so that usage of flash isn't so obvious)
« Last Edit: 08 / February / 2009, 03:45:33 by vit40 »


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Offline zosX

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Re: Problems with color when importing a .dng into photoshop cs3
« Reply #14 on: 08 / February / 2009, 08:03:12 »
The example is actually a custom white balance that does not look right, I agree. I was more interested In getting the same tones that I was getting in picasa and seeing if the custom WB would hold since the originals I had problems with had a custom WB. So the picture looks equally bad in picasa and cs3, so for me that's a win for right now. Picasa uses dcraw and while dcraw seems to work ok i need to play with it some more.

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Offline vit40

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Re: Problems with color when importing a .dng into photoshop cs3
« Reply #15 on: 08 / February / 2009, 08:11:51 »
I understand that you adjusted WB to get acceptable results, of course. My point was that "unexpected values" you had to use are clear indication that color matrix is off

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Offline zosX

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Re: Problems with color when importing a .dng into photoshop cs3
« Reply #16 on: 08 / February / 2009, 10:13:30 »
You mean the color matrix in CHDK? I could do some test shots with dng output and throw them up somewhere with their corresponding jpegs if you would like to compare. To me the jpeg should be at least, colorwise, somewhat representative of how the dng should look. I'm very much an amateur and I was pretty excited about being able to shoot some raw shots because jpeg is such an inferior format. Even tif or something would have been better..... So I guess what I'm saying is that I have no idea really what to look for in color histograms other than the simple rule that the white balance should be balanced across the middle if possible. I'm going to take some shots later on this afternoon as the sun is out FINALLY and I can get some good contrasty shots which I'll probably just make black and white anyways.... :P

I wanted to shoot some crws process them with dng4ps2 and shoot some chdk dngs as well and compare and contrast the differences.

Finally I never adjusted the white balance in photoshop. The image I posted was just dropped from explorer. I turned off the auto contrast, but other than that the white balance is "As shot" in photoshop. I thought it was fine for the most part and didn't exhibit the problems with the first set of dngs I had tried.

And thanks for responding and what not. If theres anything I can do or test, I'd be happy to do so.

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Offline vit40

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Re: Problems with color when importing a .dng into photoshop cs3
« Reply #17 on: 08 / February / 2009, 12:53:26 »
Yes, I meant the color matrix in CHDK, that was written to DNG in the camera. I think that it's the best to wait until ewavr change the matrix with a new on, hopefully better one. I went through this stuff with A620 and A650, because matrices in dcraw and dng4ps2 also aren't very good, although they are at least near (unlike this one), so I finished up doing my own calibration and, after DNG 1.2 specification came out (with Adobe profile editor), color profile also ...


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Offline ewavr

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Re: Problems with color when importing a .dng into photoshop cs3
« Reply #18 on: 08 / February / 2009, 13:53:36 »
Yes, I meant the color matrix in CHDK, that was written to DNG in the camera. I think that it's the best to wait until ewavr change the matrix with a new on, hopefully better one.

In new build #707 color matrix for A590 is copied from latest DNG4PS2 version:
Code: [Select]
0.726857 -0.176454 -0.124118
-0.071340 0.592001 0.075622
0.063222 0.050547 0.219582
« Last Edit: 08 / February / 2009, 13:56:07 by ewavr »

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Offline vit40

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Re: Problems with color when importing a .dng into photoshop cs3
« Reply #19 on: 08 / February / 2009, 14:37:20 »
This one is slightly better (applied it on 1652.dng with DngSetmatrix), but not much - still wrong positions of red and blue primary, and what's strange, exceptionally high color noise, like this was at least ISO3200 ... For experiment, I applied my matrix for A650 on 1652.dng (it is slightly modified matrix for G10), and result is way better - colors much closer to sample from Picassa and much less noise ... although that is a matrix for different sensor

evawr, BTW, any chances about limiting ISO in movie mode (question I asked several days ago in feature request section) ?
« Last Edit: 08 / February / 2009, 14:56:59 by vit40 »

 

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