Red Shift on JPG Conversion

cdhames

I'm having trouble with a red shift after converting to jpg, I was hoping someone could help out. I work in CS2 still, RAW files converted to TIFF. After I complete all of my post production on the TIFF image, I convert from Adobe RGB to sRGB (EDIT --> CONVERT TO PROFILE). Then I save a copy as a JPG for viewing purposes.

I've always noticed a slight color shift using these steps, but until now it's never been much of a problem. I've taken a break for about a year now and am just getting back into my work, so things are a little rusty. Not sure if I've forgotten something or if I've just gotten more critical of my end-work.

What's interesting is that when I open the JPG back up in photoshop, the colors appear fine. It's only when I view the JPG in a browser window, or 3rd party viewer (anything other than photo editing software) that the unpleasent red shift appears.

Here are the JPGs. The first image has the proper color tone (I had to play with with the contrast, and red/yellow values in order to get the JPG to match was I viewed in Photoshop) that I'm looking for. As you can see, the second image has a noticable red shift.

Hope someone can help!

jfriend

When you view any JPEG with non-color-managed software, even one in sRGB, on a monitor that isn't perfect sRGB (none are), you will see a color shift. That's because non-color-managed apps don't do anything with either the colorspace of the image or the monitor profile. They just dump the images right to the video card. That means you get color display errors. As LCD monitors have moved towards wider gamut display, this "error" in color with a non-color-managed application has actually gotten larger lately.

If your image looks right in a color-managed application on a calibrated display, then you're doing everything possible to display accurate colors. Non-color-managed applications and/or non-calibrated/profiled displays just don't display accurate colors.

The answer is to only use color-managed applications to view your images if you want accurate color display. In the browser world, you can either use Safari or Firefox 3. In Firefox 3, you have to specifically enable color management with a preference. In Safari, it's always on.

On my system (everyone's system behaves differently in this regard), these particular images do show a significant red shift in a non-color-managed browser, but look good in Safari (which is color-managed). I'd say, there's nothing wrong with your JPEGs.

cdhames

Hmm, thanks for the reply. I did recently purchase a wide screen LCD last month, that I've been working on, with a high gamut. That would likely explain why the shift is so much more obvious now.

Most of my work gets sent to the client in JPG format. What would you recommend I do to counteract this? Many of the people I work with aren't the computer savy type, and sending instructions to color proof their browsers isn't an ideal solution for me.

jfriend

cdhames wrote:

Hmm, thanks for the reply. I did recently purchase a wide screen LCD last month, that I've been working on, with a high gamut. That would likely explain why the shift is so much more obvious now.

Most of my work gets sent to the client in JPG format. What would you recommend I do to counteract this? Many of the people I work with aren't the computer savy type, and sending instructions to color proof their browsers isn't an ideal solution for me.

Yes, if you just got a wide gamut monitor that would explain why you see this effect more now. It's actually further from sRGB when non-color-managed software is using it. The only real answer here is for the OS and all the software running on it to become color-managed and for most monitor profiles to be close to accurate. That will happen over time (we're probably talking 4-6 years though).

There is no couteracting this effect. An uncalibrated, unprofiled system running non-color-managed software is a wildcard. It could be off in any direction. You can't aim for it. If you do aim for a particular uncalibrated system, you'll just be making it even worse on someone else's system.

Your best choice is to get the color "right" on a color-managed system because that will make good prints and you are then aiming for the center of the general population. If a particular client asks about it, you can explain that the prints are color corrected on a calibrated system to make accurate prints. Some systems out there don't display colors very accurately. It's hard to explain much more to a non-tech-saavy person. If the system has a decent monitor profile, then a color-managed browser like Safari will at least do a lot better than IE.