Exif Color Space Uncalibrated

[David Rodgers]

This is my current file workflow: open JPG shot from digital camera. Color space is sRGB, so the file title bar shows "image name" (RGB*). The asterisk means that the image color space, sRGB, is different from the one and only working color space in PSE, Adobe RGB 1998. I then save in PSD format, but uncheck the ICC profile box. Close and reopen, and now the title bar shows "image name" (RGB#). The number sign means the image is not tagged with any color space, which is correct, since I just stripped it out in the last save. Now, if I look at the file info, it says, "EXIF color space: sRGB." Seems to me it should say, "unknown," since I saved it untagged, but whatever. Now, I save the image as PSD once more, only this time, I check the box for ICC profile Adobe RGB 1998, so the image gets tagged. Close, reopen, and I get "image name" (RGB), meaning the tagged profile matches the PSE working color space. Good, that's what I want. However, now when I look at the EXIF color space listed in the file info box, it says, "uncalibrated." Anyone know why, or what this means? Sorry for the long post, but I can't seem to find out anything about this and I'm that kind of person who wants to understand everything the program is telling him. Final info; I don't use Adobe gamma for monitor color correction, in fact, I don't have any Windows color profile currently associated with my monitor. Could this be the cause? Appreciate any help or explanations of this phenomenon.

[brent bertram]

David,
The EXIF information is written by your camera into the image file. Elements doesn't modify the EXIF information. The colorspace tag that you are seeing ( whether it's sRGB or AdobeRGB) is actually embedded in the file, but not the EXIF info. That EXIF info is seperate from the embedded colorspace.

It just happens that , by default, Elements 2 and Photoshop 7 respect the EXIF info and use that as a color space on otherwise untagged images. We now have the IgnoreEXIF utilities to change that behavior, however, the EXIF information still remains, but ignored.

To be long winded about it <G> , the EXIF info is not the place where the images colorspace is imbedded. EXIF information is sort of " advisory" info for applications. Even if you had no EXIF info, like from a scanned file, you could still have your favorite colorspace embedded. Forget about EXIF info . It doesn't matter if you ignore it.

:-)

Brent

[David Rodgers]

Brent, I see you answer a lot of posts and I appreciate you taking time to look at mine. I am trying to follow your logic, so bear with me if I repeat back my interpretation of your answer. I understand that the EXIF comes from the camera. My point was that when I open an image, either untagged (no associated color profile)or tagged with a different color profile than Adobe 1998, the file info lists the EXIF color space as sRGB in both cases. Once I save the file with the Adobe 1998 color profile, the EXIF color space citation in the file information box changes to "uncalibrated." I understand that Elements is not changing the EXIF info, but why does it now read "uncalibrated"?
David

[brent bertram]

David,
Groan !!! I'm almost sorry I spoke up <G> . This has turned into an educational experience.

I can't answer the "why" question. What I see happening ( as I manipulate these images like a wildman <G> ) is interesting. It only seems to happen with the PSD format. I also tried TIF saves, but didn't see the EXIF info switch.

I think (?) that the PSD format is more "mature" than the others and that elements changes the EXIF colorspace from a "1" to a "0" .
0=uncalibrated ( or anything but sRGB)
1=sRGB

I suspect , from what little I have read , and from looking at the EXIF info using IrfanView, that what is stored in the EXIF file is either a "1" or a "0" .
Perhaps the EXIF standard is in its infancy and the committee hopes to implement more in the future, but I doubt it. I suspect that part of the save as "PSD" process is the toggling of the "1" to a "0" to indicate that the image is not the original sRGB anymore.

I also saved as a PSD in Photoshop 7, in the ColormatchRGB space and saw the same "uncalibrated" phenomenon happen.

It looks like saving as a PSD in Photoshop with any space except sRGB writes "uncalibrated" in the EXIF info . My suspicion is there are only two choices for that field , sRGB and "everything else " .

My mind is still swirling from keeping track of all these variations of files I've just created <G>.

Thanks for the exercise, Dave,

:-)

Brent
[My disjointed post is indicative of my state of mind. There may be more variations on the above theme, but i suspect that its only a case of Adobe wanting its PSD format to me as "proper" as possible . No other formats seem to touch the EXIF data at all. ]

[David Rodgers]

Brent, I'm glad you were able to duplicate this phenomenon in both Elements and Photoshop. Now I am reasonably assured that it has nothing to do with having no color profile associated with my monitor. And I know what you mean about the confusing proliferation of files resulting from the exercise. This whole thing started because I wanted to edit my files in the same color space as PSE, i.e., Adobe 1998 RGB. It required copious notes and file manipulations before I was able to figure out how to open my files in that color space consistantly. This "uncalibrated" business reminds me of determining the meaning of the # sign and * sign that magically appears/changes after the "RGB" in the file title bar when an image is open. I finally found the explanation for it at <http://user.fundy.net/morris/redirect.html?photoshop141.shtml>. In fact, those #'s and *'s are what caused me to even become aware of color space. Anyway, maybe Adobe could explain the "uncalibrated" to us, but I wouldn't know how to ask them. I guess I've flogged this to death and will leave it in the "unsolved" file for now. Glad you found it a challenge. BTW, your post times are awfully late in the evening. You either work nights, have a bad case of insomnia, or find this entire PSE thing totally consumming....like me!
David

[brent bertram]

David,
Most of my posts are early in the morning in Michigan. I'm up at 4:30 daily ( the dogs are trained to wake me <G> ). My guess is that with only two choices, 0 or 1 in the EXIF field, it is functionally useless. I have used the IgnoreEXIF utility ever since it came out for Photoshop. It also worked for Elements with a little modification, but now Adobe has released the "official" one, and I think everyone should use it.

Then, just being in Full Color Management mode ( AdobeRGB space ) means you'll save your image in that space. Elements won't waste any of our time "honoring" the EXIF colorspace .

This little exercise was the sort of thing that appeals to me, too. I'm more of a technician than a graphics person.

:-)

Brent