Question about Save for Web

I am running PS 7 on a Mac, OS 10.4. I have some pictures in TIFF format that I need to reduce in size to meet the 75 KB posting requirements on a web site. If I use Save for Web, I notice that the color saturation is reduced in the smaller JPEG files, compared to what it is when you just open the original ~ 1.5 MB files in a PS window.

This would make sense, I guess, but what I also notice is that in the Save for Web window, where I have the original, full size file on the left and the previewed compressed file on the right, even the original is displayed with the reduced color saturation. So the file saved for the web is matching those already reduced saturation colors.
Can someone explain what is happening, and if there is anything I can do to retain the better color saturation?

Your image is probably in AdobeRGB. Before saving it for the web, use ‘Convert to profile’ and convert it to sRGB.

Your image is probably in AdobeRGB. Before saving it for the web, use ‘Convert to profile’ and convert it to sRGB.

That works, thanks. One more question please.

If I do the conversion and then save the file, the next time I open it, it again has the color issue when saving for the web. I again have to do the conversion. It apparently doesn’t "stick" with the file.
I think I will just change the default PS color space to sRGB.

Your image is probably in AdobeRGB. Before saving it for the web, use ‘Convert to profile’ and convert it to sRGB.

That works, thanks. One more question please.

If I do the conversion and then save the file, the next time I open it, it again has the color issue when saving for the web. I again have to do the conversion. It apparently doesn’t "stick" with the file.
I think I will just change the default PS color space to sRGB.

and this of course, leads to the question whether there are any sense/value in converting an original sRGB to AdobeRGB.

and this of course, leads to the question whether there are any sense/value in converting an original sRGB to AdobeRGB.

I don’t think the OP said anywhere that he changed the original from sRGB to AdobeRGB, but if he does, it is indeed senseless. I agree with the OP that it may be better for him to work in sRGB all the way. If you do not understand color management, as he already said, working in another color space will only create problems like this one.

On Mon, 21 Jan 2008 10:23:56 +0100, (Johan W.
Elzenga) wrote:

Dave said:

and this of course, leads to the question whether there are any sense/value in converting an original sRGB to AdobeRGB.

Johan Replied:

I don’t think the OP said anywhere that he changed the original from sRGB to AdobeRGB, but if he does, it is indeed senseless. I agree with the OP that it may be better for him to work in sRGB all the way. If you do not understand color management, as he already said, working in another color space will only create problems like this one.

No, you misunderstood. I did not hold that the OP said it, and it could have been a question completely on its own. I only saw the question fitting there because it came to mind when reading this thread.
But, you answered the way I thought you would, by calling it senseless.

Dave wrote:

On Mon, 21 Jan 2008 10:23:56 +0100, (Johan W.
Elzenga) wrote:

Dave said:

and this of course, leads to the question whether there are any sense/value in converting an original sRGB to AdobeRGB.

Johan Replied:

I don’t think the OP said anywhere that he changed the original from sRGB to AdobeRGB, but if he does, it is indeed senseless. I agree with the OP that it may be better for him to work in sRGB all the way. If you do not understand color management, as he already said, working in another color space will only create problems like this one.

No, you misunderstood. I did not hold that the OP said it, and it could have been a question completely on its own. I only saw the question fitting there because it came to mind when reading this thread.
But, you answered the way I thought you would, by calling it senseless.

OK, got it. To elaborate a little: Converting an sRGB image to AdobeRGB is a bit like pouring a gallon of milk into a 1.5 gallon bottle. You do have a bigger bottle now, but the amount of milk stays the same.

On Mon, 21 Jan 2008 16:22:50 +0100, (Johan W.
Elzenga) wrote:

Dave wrote:

On Mon, 21 Jan 2008 10:23:56 +0100, (Johan W.
Elzenga) wrote:

Dave said:

and this of course, leads to the question whether there are any sense/value in converting an original sRGB to AdobeRGB.

Johan Replied:

I don’t think the OP said anywhere that he changed the original from sRGB to AdobeRGB, but if he does, it is indeed senseless. I agree with the OP that it may be better for him to work in sRGB all the way. If you do not understand color management, as he already said, working in another color space will only create problems like this one.

No, you misunderstood. I did not hold that the OP said it, and it could have been a question completely on its own. I only saw the question fitting there because it came to mind when reading this thread.
But, you answered the way I thought you would, by calling it senseless.

OK, got it. To elaborate a little: Converting an sRGB image to AdobeRGB is a bit like pouring a gallon of milk into a 1.5 gallon bottle. You do have a bigger bottle now, but the amount of milk stays the same.

LOL, I like your description:-)
and thanks, that is what commons sense said
but I wanted you to confirm it.

Dave

But then again, does this mean that the only time it’ll make sense converting to AdobeRGB, is when shooting RAW? Because on JPG, the default mode is sRGB. Fuji Finepix s9600

Dave wrote:

But then again, does this mean that the only time it’ll make sense converting to AdobeRGB, is when shooting RAW? Because on JPG, the default mode is sRGB. Fuji Finepix s9600

Yes, if that camera cannot shoot in AdobeRGB JPEG, it only makes sense to use AdobeRGB when you shoot in RAW.

OK, got it. To elaborate a little: Converting an sRGB image to AdobeRGB is a bit like pouring a gallon of milk into a 1.5 gallon bottle. You do have a bigger bottle now, but the amount of milk stays the same.

"Johan W. Elzenga" wrote in message

OK, got it. To elaborate a little: Converting an sRGB image to AdobeRGB is a bit like pouring a gallon of milk into a 1.5 gallon bottle. You do have a bigger bottle now, but the amount of milk stays the same.

I agree with your conclusion, but not the reason. sRGB is a smaller color space that RIB. For that reason any algorithm can only guess at what color is needed to fill the space. The upsizing therefore lead to color distortions.
I am anticipating someone posting that they got do this without loss. Great, I congratulate them, in advance, on their good luck. But, I would not count on getting away with the upsizing on a regular basis.

—
Peter

"Johan W. Elzenga" wrote in message

OK, got it. To elaborate a little: Converting an sRGB image to AdobeRGB is a bit like pouring a gallon of milk into a 1.5 gallon bottle. You do have a bigger bottle now, but the amount of milk stays the same.

I agree with your conclusion, but not the reason. sRGB is a smaller color space that RIB. For that reason any algorithm can only guess at what color is needed to fill the space. The upsizing therefore lead to color distortions.

Peter wrote:

"Johan W. Elzenga" wrote in message

OK, got it. To elaborate a little: Converting an sRGB image to AdobeRGB is a bit like pouring a gallon of milk into a 1.5 gallon bottle. You do have a bigger bottle now, but the amount of milk stays the same.

I agree with your conclusion, but not the reason. sRGB is a smaller color space that RIB. For that reason any algorithm can only guess at what color
is needed to fill the space. The upsizing therefore lead to color distortions.

Nope. The colors will simply be matched one by one, because sRGB does not have any colors that are out of gamut in AdobeRGB. There is nothing to guess. You will end up with an AdobeRGB image, but the *actual* colors will only occupy the sRGB area within the AdobeRGB space. The rest will be empty.