Affinity Photo image looks (is?) darker and desaturated compared to vray buffer and everything else

[dennisqdw]

Hi, I'm trying to make the complete transition from photoshop to affinity, and I seem to be having a peculiar problem. When I render an exr file using 3ds Max and Vray (either 16 or 32 bit), and open it in AF it looks somewhat darker and somewhat desaturated. It is not the same big difference as from the typical gamma shift from 1 to 2.2. I am working in sRGB colorspace in AF, and viewing it as sRGB in the vray buffer (and working in vray with linear workflow rendering). And for what it's worth I've also saved the image as an 8 bit tif just as a test, and everything I'm describing here is the same for that image too.

When I compare the RGB values of a single pixel, AF's values are indeed lower than those in the vray buffer. But here's where it really gets weird. If I save the file from AF as a tif, or jpeg (with sRGB profile), and open it in the vray buffer, or even windows image viewer, they all match vray, and none of them match AF. I feel like there must be a preference setting somewhere that I've missed.

Under the color tab, as mentioned, both RGB color profiles are set to sRGB. I've tried changing Rendering Intent to each of the 4 choices with no visible difference, but it is currently on Relative Colorimetric. Black point compensation is checked on. I don't know if "Grayscale Color Profile" can be changed from D50 to anything else, as there are no other options, or even if that matters. BTW I am using a color calibrated monitor that is set to sRGB color space, and D65, luminance 120.

Obviously, I can't color correct in AF if I don't see the image correctly. Does anyone have any ideas what's going on? It's driving me nuts.

thanx to anyone who knows what's going on. --ds

[dennisqdw]

Ok, I've found out a little more info from this very helpful forum post:

So when I use the 32 bit preview as mentioned here, the image matches the vray buffer perfectly. So I need to correct my comment above ("When I compare the RGB values of a single pixel, AF's values are indeed lower than those in the vray buffer.") That pixel disparity comes from the fact that the RGB info values are accurate to the uncorrected gamma, but the image is displayed with gamma correction in order to look "correct". My theory at this point, which is only a guess, is that AP's display gamma correction must be somewhat different than that of vray (however that sort of complicated math is done). Assuming I'm correct, I'm still in the same boat -the image in AP looks a little desaturated, and less "sharp", although I'm guessing that appearance of sharpness is caused by perhaps less contrast?

I've attached a screen grab showing the "same" picture, from left to right, in the vray window, Windows Photo Viewer, and AP. And actually, as you can see they each look a little different from the others (and indeed selecting the same single pixel, will reveal that this is not just an illusion). But to my eyes, the AP image is the most desaturated looking. The differences aren't huge, but they are noticeable.

example of color differences.tif

[Dan C]

Hi @dennisqdw,

Sorry to hear you're having trouble and our sincerest apologies for the delayed response here!

We'd like to investigate this issue further for you, but in order to do that we'd like to request a few sample files from yourself.

Can you please upload the images shown in your screenshot to the below link for me, then once uploaded please reply here to let me know?

https://www.dropbox.com/request/EAERohyIDbPjSQswtiDu

I will be forwarding this thread through to our Photo expert and QA team to try and determine the cause of this for you, as unfortunately I'm not personally 'well-versed' to EXR workflows and I would not wish to provide incorrect information.

Many thanks in advance

[dennisqdw]

Thanx for responding. I have uploaded the file. I'm growing more certain of my "theory" that each software does a somewhat different conversion to display in sRGB space, but I'd love to hear from the experts 😀.

thanx --ds

[dennisqdw]

23 hours ago, BofG said:

I don't know what vray does, but Windows Photo Viewer isn't colour managed, I think it uses the monitor's colour space rather than assuming sRGB. Affinity is fully colour managed and will also correctly use your monitor's profile.

Yes, that makes sense about Windows Photo Viewer. I included it's window because in many ways it's closer to Vray, than Affinity. The monitor is calibrated to sRGB, and Vray definitely color manages to sRGB when you select that option. As I'm rendering in linear space the image is in "fact" dark, until one selects sRGB correction. And of course Affinity adds that correction by default. But now that you've brought up the monitor, it makes me wonder if the two applications interact with the monitor's space somewhat differently. The monitor fwiw is an HP z32x and calibrated with the HP Dreamcolor Solution app. Again, this is all guesswork on my part. Thanx for the response.

[dennisqdw]

I'm using the default profiles that come with vray and Affinity. In the case of Affinity it's sRGB IEC61966-2.1 (Linear). But, indeed, if you're last comment is the case, then that's just the way it is, and I'll have to deal with it. I wasn't sure whether or not each app's profiles are supposed to match or not. I wanted to make certain that I'm not making a mistake at my end. Eventually, I'm converting to Adobe 98 for print. thanx for the response.