Prophoto RGB Photos look dark on the Web

[Steve]

Thanks Steve,

What really puzzels me is photo #2 I posted up with an embedded profile of Srgb, if you check it now no longer has an embedded profile, do you know why?

Thanks,

Frank

Looks like MrTom answered your question.

 

[Tom Mann]

MrT: "...I checked it and the profile is there..."

Sorta ...kinda...

ICC profile information is / can be stored in two different ways in JPGs. The first, more common method, is to simply place a "tag" in the EXIF data. This is either a short or long integer (ie, only a byte or two long) and simply specifies the name of one of the standard color spaces. If you want to see the correspondence between the INT stored in this field, and each of the common color spaces, Google something like {EXIF JPEG metadata ICC profile tag information}. This should take you right to the correct part of the (long) internationally agreed upon standard.

I'm fairly sure that Bridge (ie, what was used by MrT) only reports the presence or absence of this one INT.

The second way ICC info is stored in an image file is by using what is called an "embedded profile". This is essentially a large matrix of numbers, much like a look-up table. It specifies how the RGB data for each pixel in the file should be transformed to get it into the desired working color space. Because this method adds noticeably to the file size, it is rarely used by web development people who want pages with lots of small images to load quickly. However, photographers who might be using one of the less common color spaces, but want to make absolutely sure their image is seen correctly on ICC-compliant software will use this method. Personally, I'm a "belt AND suspenders" type of guy, so I use both.

I checked, and the OP's image #2 (as posted on PSG) only seems to have the "Tag", not an embedded profile, so Franck is correct.

Since I only have a copy of his image after he posted it to PSG, I can't verify that there was an embedded profile before he posted it. However, because forum software is always trying to save space, and is known to do strange things to colors, I wouldn't be surprised at all if the forum software stripped the embedded profile, but left the tag.

HTH,

Tom M

 

[MrToM]

Looks like MrTom answered your question.

No....I didn't.

...I checked, and the OP's image #2 (as posted on PSG) only seems to have the "Tag", not an embedded profile, so Franck is correct...

Well thanks Adobe for making me look like a crazy fool!

That all makes perfect sense Mr Mann, but when I saved that image as a PSD with an embedded profile I still get the same results as you've shown...



So....Am I going about saving the profile with the PSD in completely the wrong way? (Or not as the case may be.)
Is the checkbox for saving the ICC profile in the "Save As..." window a complete red herring?

That bit doesn't make sense.....so what's going on?

Confusing to say the least! LOL.

Regards.
MrTom.

 

[Steve]

No....I didn't.

Well thanks Adobe for making me look like a crazy fool!
MrTom.

Ah, I guess not. [highfive]

 

[MrToM]

LOL....I'm so sorry for this but I just couldn't resist...

Sorry its a bit off topic, and no offence to anyone.....It's just my warped sense of British humour. (And I need my medication.)

Very Best Regards.
MrTom.

 

[francklouis]

Thanks to both of you steve and Mr Tom and I still don’t havea clear answer to the original way back 4 pages ago, and now it seems we haveanother problem to deal with: What are websites doing to our images once weupload them.
Do websites change the way an uploaded photo looks byremoving the embedded color profile as the PSG website has done, and if that isthe case how does one compensate so that what we see in PScc is what we seewhen posting to a website?

Thanks,

Frank

 

[Steve]

Your welcome Frank
To the best of my knowledge PSG doesn't do anything to your image.
It has to do with your OS and the web viewer it supports.

I was made aware that as of 12/1/2014 of some Image viewing / editing programs that display ProPhoto images correctly on a (Win 8) computer are:
Internet Explorer 11.0.9600 (ie, current version)
Safari 5.1.7
Chrome 39.0.2171.71
Firefox can display ProPhoto correctly, but may need custom settings
Windows 8 Photo Viewer
Picasa
Picasa Photo Viewer stand-alone
Win 8 "Photos" app

But Windows 8 users total about 10%
Windows 7 about 48% and Windows XP about 30%

So if you're post images to people on the web, the majority aren't Windows 8 user.
So you should remember that anything for the general public should go out as an sRGB file.
Period.
End of story.
Doing this ensures that pretty much no matter what software Mr. John Q. Public uses on his system to view your images, they will look the almost exactly the same.

Also remember that even if you go through ACR and select some working color space other than sRGB, in a perfect world, all your viewers would be using only fully ICC-compliant software to view your images, so they shouldn't see any difference, either. Unfortunately, there is a lot of software still in use that is not ICC compliant. The situation is getting much better, but a lot of potential viewers are using older software that didn't have a clue what to do when it ran into an image in anything except sRGB.

These are all points I've mentioned in other recent threads.

 

[Tom Mann]

Hey, Guys - Sorry I've been absent for the last day or two, but between end-of-semester duties, preparing the house for Christmas, getting ready for a trip, etc. I simply didn't have a moment to spare. Anyway, I thought I better catch up with some of these threads that seem to have some loose ends.

@francklouis:

"...I still don’t have a clear answer to the original way back 4 pages ago, ..."

Actually, I believe you do. In fact, the answer was given to you several times, most recently, by Steve. The answer is that for the most consistent viewing of your images with different hardware and software, you must convert (not "assign") your image from whatever working color space you have been using to sRGB before you send it out for viewing by the general public, or printing at low-end print shops. To use Steve's words, "Period. End of story", LOL. The only thing I would add to this is that you do have two ways to convert to sRGB: You can either use "Save For Web" (under the "File" menu), or you can use the "Convert to Profile" (under the Edit menu) followed by a "Save As".

"...and now it seems we have another problem to deal with: What are websites doing to our images once we upload them. Do websites change the way an uploaded photo looks by removing the embedded color profile as the PSG website has done, and if that is the case how does one compensate so that what we see in PS-CC is what we see when posting to a website? ..."

The short answer is, once again, convert your image to sRGB before posting on a website. That way, even if the website / forum software strips out either the color space tag, or the embedded profile, or both, the worst that can happen is that the image turns into one with no color space specified. Such images, are, by default, always interpreted as sRGB, so, once again, if you uploaded it in sRGB, you will have no problems.


@MrTom:

re: "....Am I going about saving the profile with the PSD in completely the wrong way? (Or not as the case may be.) Is the checkbox for saving the ICC profile in the "Save As..." window a complete red herring? "

The topic of color space tags, vs embedded profiles is *REALLY* messy. Prompted by your question, I just spent the last hour or so doing some really detailed testing trying to determine which (common) software recognizes tags, which recognizes embedded profiles, with recognizes neither, and what does the software do if it encounters both, and what do they do when they contradict each other. Also, prompted by your question, I also looked at whether or not the "CMM flags" field actually tells us anything when it says, "Not Embedded".

First, the way to independently turn on and turn off ICC tags and ICC embedded profiles is using the two check boxes in "Save for Web", not the single color-space-related check box in "Save As".

Using the two different "Save for Web" ICC-related check boxes, it was trivial to see that they have different effects on the metadata. If you want to look at this yourself, just scroll down past where you were looking in EXIF_tool_gui, and you'll see that quite a few more lines at the end of the section that appear when you check "embed profile" using "Save for Web". The values for these fields (ie, the "tone reproduction curves") will contain values such as "curves" or "lookup tables" (aka, LUTs), depending on which method they used to embed the profile.

The really disappointing thing is that, like you observed in your experiments using the "Save As" method, the "CMM flags" never changed whether or not the image file actually contained an embedded profile or not. To be honest, I was shocked by this, but apparently, Adobe either doesn't bother to set this field at all, or else, they use it for some other purpose. Instead, when they actually embed a profile, it seems that they expect the receiving software to test whether the fields that contain the actual embedded profile data are present or not.

Knowing this, I re-checked the OP's images. His image #1 was tagged ProPhoto, but didn't have an embedded profile, whereas his image #2 was tagged sRGB, and also contained an embedded profile. For both of these, I "clicked through" to get the file that he uploaded, not the in-forum mid-sized preview, which could easily be different. I just didn't have time to do this.

Before I sign off, I'll just describe one very interesting test that I did: At least Windows 8.1's "Photo Viewer" seemed to display ProPhoto pix perfectly whether just the tag was there, whether just the embedded profile (but no tag) was there, or whether both were there. And, exactly as expected, the image looked absolutely awful when neither one was present (ie, so it interpreted the image as an sRGB). I did not see such consistent behavior in any of the other software that I tried with the exception of Firefox, with full color management turned on.

Now, I really have to sign off: I think that the OP has a clear, very definite answer (ie, "always convert to sRGB when an image is going out to the public"), but the more advanced, detailed points that you and I are getting into probably deserves to be put into its own thread and discussed separately. That being said, I am running REALLY short on time these days, so if we do start such a thread, I can tell you right now that my response time is going to be horrible, at least on and off for the next few weeks.

Best regards,

Tom M

 

[MrToM]

Well there's food for thought!

Very interesting Mr Mann, and many thanks for taking the time to experiment and explain all that, much appreciated.

I'm sure that will be of interest to many others too.

Regards.
MrTom.

 

[francklouis]

Thanks Tom and MR Tom, it all makes sense now.

Frank

Hey, Guys - Sorry I've been absent for the last day or two, but between end-of-semester duties, preparing the house for Christmas, getting ready for a trip, etc. I simply didn't have a moment to spare. Anyway, I thought I better catch up with some of these threads that seem to have some loose ends.

@francklouis:

"...I still don’t have a clear answer to the original way back 4 pages ago, ..."

Actually, I believe you do. In fact, the answer was given to you several times, most recently, by Steve. The answer is that for the most consistent viewing of your images with different hardware and software, you must convert (not "assign") your image from whatever working color space you have been using to sRGB before you send it out for viewing by the general public, or printing at low-end print shops. To use Steve's words, "Period. End of story", LOL. The only thing I would add to this is that you do have two ways to convert to sRGB: You can either use "Save For Web" (under the "File" menu), or you can use the "Convert to Profile" (under the Edit menu) followed by a "Save As".

"...and now it seems we have another problem to deal with: What are websites doing to our images once we upload them. Do websites change the way an uploaded photo looks by removing the embedded color profile as the PSG website has done, and if that is the case how does one compensate so that what we see in PS-CC is what we see when posting to a website? ..."

The short answer is, once again, convert your image to sRGB before posting on a website. That way, even if the website / forum software strips out either the color space tag, or the embedded profile, or both, the worst that can happen is that the image turns into one with no color space specified. Such images, are, by default, always interpreted as sRGB, so, once again, if you uploaded it in sRGB, you will have no problems.


@MrTom:

re: "....Am I going about saving the profile with the PSD in completely the wrong way? (Or not as the case may be.) Is the checkbox for saving the ICC profile in the "Save As..." window a complete red herring? "

The topic of color space tags, vs embedded profiles is *REALLY* messy. Prompted by your question, I just spent the last hour or so doing some really detailed testing trying to determine which (common) software recognizes tags, which recognizes embedded profiles, with recognizes neither, and what does the software do if it encounters both, and what do they do when they contradict each other. Also, prompted by your question, I also looked at whether or not the "CMM flags" field actually tells us anything when it says, "Not Embedded".

First, the way to independently turn on and turn off ICC tags and ICC embedded profiles is using the two check boxes in "Save for Web", not the single color-space-related check box in "Save As".

Using the two different "Save for Web" ICC-related check boxes, it was trivial to see that they have different effects on the metadata. If you want to look at this yourself, just scroll down past where you were looking in EXIF_tool_gui, and you'll see that quite a few more lines at the end of the section that appear when you check "embed profile" using "Save for Web". The values for these fields (ie, the "tone reproduction curves") will contain values such as "curves" or "lookup tables" (aka, LUTs), depending on which method they used to embed the profile.

The really disappointing thing is that, like you observed in your experiments using the "Save As" method, the "CMM flags" never changed whether or not the image file actually contained an embedded profile or not. To be honest, I was shocked by this, but apparently, Adobe either doesn't bother to set this field at all, or else, they use it for some other purpose. Instead, when they actually embed a profile, it seems that they expect the receiving software to test whether the fields that contain the actual embedded profile data are present or not.

Knowing this, I re-checked the OP's images. His image #1 was tagged ProPhoto, but didn't have an embedded profile, whereas his image #2 was tagged sRGB, and also contained an embedded profile. For both of these, I "clicked through" to get the file that he uploaded, not the in-forum mid-sized preview, which could easily be different. I just didn't have time to do this.

Before I sign off, I'll just describe one very interesting test that I did: At least Windows 8.1's "Photo Viewer" seemed to display ProPhoto pix perfectly whether just the tag was there, whether just the embedded profile (but no tag) was there, or whether both were there. And, exactly as expected, the image looked absolutely awful when neither one was present (ie, so it interpreted the image as an sRGB). I did not see such consistent behavior in any of the other software that I tried with the exception of Firefox, with full color management turned on.

Now, I really have to sign off: I think that the OP has a clear, very definite answer (ie, "always convert to sRGB when an image is going out to the public"), but the more advanced, detailed points that you and I are getting into probably deserves to be put into its own thread and discussed separately. That being said, I am running REALLY short on time these days, so if we do start such a thread, I can tell you right now that my response time is going to be horrible, at least on and off for the next few weeks.

Best regards,

Tom M