jpeg color does not match Photoshop color

[thebestcpu]

Hi Puppychew

I took the upper pair of images of he istar hue tests and loaded them into PS on my end. With a cut and paste (and them Layers alignment) I overlayed the PS and Firefox images and both toggled between them and also applied a blend of difference to see how close they were. Any differences were imperceptible to the human eye so I say you have a match.

Note that the text we did has some limitations since the side by side hue test image were not at 100% magnification, they were both at different magnifications, and the process of saving the images on the screen (which are in your monitor color space) and sending them as compressed sRGB images can change this just a bit.

Nevertheless, they were a visual match. Note that your eye will perceive colors differently depending on the surround tones and colors. A field of color surround by white or gray will look different that colors surrounding by black. Just as an example of simple tone differences, the image below demonstrates the "Cornsweet Illusion". On the left, the upper chip and the lower chip have the exact same gray tone. All I did on the right is use the exact same image and place a black band over the middle (you can use you finger over the left one to confirm its the same image). The transition between the two chips creates the illusion that the chips are of a different gray tone (yet they are not).



I got this out of a journal yet could not find the reference. I will try and find it and put in such reference for proper credit if I can find it later.

As far as the second image from Tom Mann. The way to download the image from the web site is to click the image, click again and then again until you have the maximum magnification. Then right click and save the file to your disk (no screen capture involved and same as mine). The image is already in sRGB and the size is 1200 x 1500 pixels. For the experiments to work best it is important to download in this manner.

When you do come across an image with no embedded profile and get the warning message:
- If you chose the working space option, for an RGB image it will use the working space RGB color space as set in Edit > Color Settings
- If you chose assigning a color space, then it will use the one you assign

Note that assigning a color space does nothing but effectively embed that color space with the data. It is not different than if someone gives you an air temperature number yet does not give you a temperature scale to go with it. The temperature data is meaningless without the temperature scale. Similarly, the color data is meaningless without a color scale (color space/profile). So all you are doing is including the color scale so the color management system knows how to interpret the color data properly.

The color space that should be assigned is the color space with which the color data was originally created. In this case is was sRGB. However, if downloaded correctly you would not need to assign a color space.

Hope that helps.

 

[thebestcpu]

One more thing Puppychew.
What is the brand name and model of the monitor you are using in these experiments?

 

[puppychew]

My monitor is Asus - Hdmi

I will make sure I use the Assign profile for all images.

Here is the new test sample. I see the yellow lilly and the skin tone are richer on the Foxfire image.

 

[Tom Mann]

Welcome back, Puppy. I hope you had a nice weekend!

A few things ...

1. I'm a "belt AND suspenders" type of guy when it comes to color management, so, just to check that Firefox is indeed correctly setup to display sRGB images, could you pls. post side-by-side screenshots of my test image with PS (on the left), and Chrome (on the right).

2. re your statement, "I will make sure I use the Assign profile for all images.", that's not quite correct. There is are very good reasons that Photoshop includes both the "Assign to" and the "Convert to" commands. Sometimes you want one, sometimes you want the other. As John effectively said, you use the "Assign to" command when you know the source color profile, but the sender of the image simply forgot to tag the image with the name of a color profile. You might also use the "Assign to" command if the image you are working on looks downright bizarre and you don't know (and can't find out) what the original color profile was, so you try a bunch (of source color profiles, not printer profiles) see if any of them make a huge improvement in the image. One might also use the "Assign to" command for artistic purposes, ie, to intentionally make the colors look weird.

HOWEVER YOU SHOULD USE "CONVERT TO" IF you know the source color profile, but you want to work in another color space. For example, you are putting together a composite, everything else in the composite is in sRGB, but you need to include an image that is in Adobe RGB. Then, to get the proper match, you need to CONVERT NOT ASSIGN that image to sRGB.

3. In case you haven't thought of this, we have absolutely no idea of how these images actually appear to you. This is because screen shots only record the data that is being sent to your monitor, not what you are actually seeing with your eyes. I suspect this may be the reason John asked for the name and model of your monitor. Specifically, some monitors are so bad, even the best hardware calibration systems can't bring them into full compliance with (say) the sRGB spec.

4. "HDMI" is not the model name for your Asus monitor - "HDMI" simply tells us that it can be connected using an HDMI cable. Look on the back and see if there is any other information about it. Failing that, could you tell us how old it is, and roughly how much you paid for it.

Best regards,

Tom M

 

[puppychew]

Sorry for the delay. I was waiting for your reply but this page didn't update.

1) I have to get back to you on this. Chrome does not show up. My friend will help me find it as he did firefox.

2)I am confused with this message. Which should I use?


4) Monitor is Asus PA248Q it cost under $200.

 

[puppychew]

Here is PS and chrome
Does chrome need to be set up for color mgt like firefox?

 

[thebestcpu]

Hi Puppychew

A few items

1) Here is detailed online report about your monitor. I mainly wanted to confirm that your monitor was not a wide gamut monitor and it was not. Its default starts very close to sRGB: http://www.tftcentral.co.uk/reviews/asus_pa248q.htm

2) For the image on assigned a color space, in that partricular case it does not matter if you assign it sRGB or use the other option to assign the default working space (which is also sRGB. Since they are both the same color space, the same color profile will be associated with that image.

3) However, as per a previous post I made, you did not properly download the image. If your either did a screen capture or just right clicked on the image and downloaded in Windows 7, you will download a reduced resolution version that has no embedded profile. I checked this on my virtual Win 7 installation on my Mac.

So we do not introduce any more variables into the system, please download the images using the following process
- hover over the original test image. A hand with a finger pointing should appear as the cursor. Click on the image and it will open up by itself. At this point it may show a cursor with a "-" sign indicating indicating you can click again to magnify (that is an optional step)
- Once you have the isolated image, now right click on the image and choose the save image option.
- When using this approach you will get the full 1200x1500 pixel image with the embedded sRGB profile.

This will remove two areas of uncertainly. While the smaller image on the post very well may still have the color data in sRGB, I do not know what the Photoshop Gurus site does for these compressed images it creates (why take the risk of that uncertainty)

Also, since you have downloaded the image with no embedded profile, while you have assigned the profile in Photoshop, you most likely opened the untagged image in the browser so that also leaves some uncertainly.

Sooooo, per my previous post, please download the images as I specified so the color profile/space is embedded into the image and PS will not ask for any assignment and the browsers will be as color happy as a browser can be

Then after that, put PS display side by side with the browser displays and we can use that as a comparison.

Just trying to minimize the variables and get us back on course.

Hope this is understandable.

 

[puppychew]

Thanks for your through explanation. You had earlier stated (post 61) that I must enlarge the image before saving it. I never knew that.
In the above posts that is how I did it. When opening the image in ps, I was not prompted to assign a profile.

 

[Tom Mann]

...You had earlier stated (post 61) that I must enlarge the image before saving it. I never knew that. In the above posts that is how I did it. ..

I presume you are referring to this statement, "...The way to download the image from the web site is to click the image, click again and then again until you have the maximum magnification. Then right click and save the file to your disk (no screen capture involved and same as mine). The image is already in sRGB and the size is 1200 x 1500 pixels. For the experiments to work best it is important to download in this manner...".


To restate what John said in Post #67, the reason for this procedure has absolutely nothing to do with enlargement. The reason for following this procedure is that, as he pointed out, the in-forum preview image and screen grab images are not the same as the images uploaded to the forum (aka, "the original"). They typically have been reduced to much smaller pixel dimensions than the original, are compressed at quite low quality factors, and, in the case of the in-forum previews, will have color management information stripped from them, and, in the case of screen grabs, will typically have the color profile for your monitor added to them. In contrast, by following the procedure he outlined, you download an exact copy of whatever was uploaded with no modification.

I should add that, in fact, every image that you download from this forum for critical analysis purposes should be downloaded in the way that he described.

HTH,

Tom M

 

[puppychew]

That's good to know. I will do it that way all the time now. Can you see a difference between firefox and chrome?

 

[Tom Mann]

puppychew - re your question, "...Does chrome need to be set up for color mgt like firefox?..."

As far as I know, even the most recent version of Chrome is not fully color managed, and, I don't think there are any configuration changes one can make in Chrome to turn on full color management analogously to what one can do in Firefox. In fact, this lack of tweakability was exactly why I was interested in you checking out the image under question in chrome.

The last time I checked, straight out of the box, Chrome should display sRGB files the same as a correctly configured Firefox installation whether the image is tagged as sRGB or not, and whether the full profile is embedded in the image or not. We are now reasonably confident that with the exception of screen grabs (which often have your monitor profile embedded), and in-line forum preview images, you are now testing you system *only* with images that are unambiguously sRGB and either tagged as such and/or carry the sRGB embedded profile and these should display identically in both Firefox and Chrome.

To be blunt, I wasn't sure if you had configured Firefox correctly (at least for sRGB files), and the test using Chrome was just double-checking that you had done this correctly (at least for this subset of image files).

Tom M

 

[Tom Mann]

That's good to know. I will do it that way all the time now. Can you see a difference between firefox and chrome?

Sorry - we were typing at the same time.

No, I didn't see any obvious differences between FF and Chrome, and that's great. I see exactly the same difference between PS and FF, and between PS and Chrome. Finally, I am confident that we now should have PS, FF, (and Chrome) all configured to display sRGB files identically, and they are not. This is troubling. I have to think about this a bit.

Tom M

 

[thebestcpu]

Hi Puppychew

While the Hue test image I supplied and the side by side in Firefox look very good with minimal differences. However, Tom Mann's test image look different that PS in both FireFox and Chrome.

The good news is that the PS image looks spot on when I bring it back in to my computer and compare to the original.

This would imply that the color management path for FireFox and Chrome still have an issue yet going through PS looks good.

I will assume that all prior steps have been followed in regards to getting the correct image with the embedded profile. I was concerned that you may have not done that given you post #65 which I inferred that you were still seeing an image with no embedded profile.

I will suggest some next steps yet wanted to let you know that suggestions given have been to try and nail the most common problems. I do not think yours is one of the common problems. The other issue is that, by digging in to so many areas, the the possibility of pilot error comes in to to play that something was changed and through to be right by all parties, yet was not input correctly so continuing down more paths could end up having us chase our tails (i.e. you don't catch the problem). If we go down all of the most likely paths, then a detailed step by step of every possible error point with screen shots would be needed to get to root cause. That in my opinion may be beyond productive interchange with forum posts. If we get to that point, you may need expert help from someone who can remotely access your machine to go through and verify every setting, provide files directly, download files directly from your machine to really probe in for what is going on. It is so much easier with hands on when there is a tough problem. All in my opinion. Also, since I am not a Windows expert on their OS related Color Management settings, that person would not be me.

I also think to insure accuracy, we are also at a point where we would need not only screen shots, yet the actual files. This means you would need to share the files through some file sharing service.

Along with that, it would be important what process you are using to obtain your screen shot (exact workflow). Which screenshot software etc. I notice that the images that show up on Photoshop Gurus web site are all sRGB. I would prefer to see the actual screen shot data which should include the embeded monitor color profile. This either implies you are post processing the screen shot (another source of potential error) or that your monitor profile is incorrect and sRGB is being used as the profile (not what was set by your Spyder system).

So before getting into my suggested next steps:
- please provide screenshots in their native condition and not post processed so we can see the monitor profile being used
- Not as critical yet nice would be for that format to be PNG instead of JPEG (avoid compression artifacts which can also shift colors)
- Please determine a way that you can file share with us so we have direct access to the files

With the above said, there are two steps I will suggest. Those suggestions are based on the assumption that Color Management is working for PS and is not yet working for FireFox and Chrome. I am also guessing that the problem is with the Windows 7 Color Management settings. Note these are just guesses based on that there is no pilot error in previous instructions, and that there is a visible difference between PS and Firefox/Chrome images on the display.

There are several steps to try and weed out the issue with my assumed hypothesis.
1) If you make any setting changes in the browsers, please make sure you close and restart your browser to make sure the settings are properly applied (Did you reset your browser at some point after making setting changes?)

2) Please read/reread that information in the following link: http://www.laszlopusztai.net/2009/08/23/stop-losing-display-calibration-with-windows-7/
In particular this time, in the first section in the Devices Tab, please use the "Identify Monitor" button to verify which monitor is being displayed for the associated ICC profile. If the number on your 24 inch Asus diplay shows a different number than in the dropdown on the Devices Tab, change the dropdown to show the 24 inch Asus monitor.

I think the cut and pastes from the article may be an older version of Win 7 and may be somewhat different, yet if you do have the "Use my Settings for this Device" checkbox, do check that box. Does the ICC profile generated by your Spyder software/hardware show up in the lower box on this page. If not, something was not set right or was reset somewhere in the process (earlier versions of Win 7 had this issue). If it is not there, add that profile with the Add button below (you may have to search for it on your system) and remove the incorrect one. Please let us know if this is not set up right via before and after screen shots if you make a change.



3) Note that the browser in their default configuration of Color Management query the OS for what monitor profile to use. It is possible that the OS is not sending the correct profile especially if we have issues in #2 above. There is a way to hardwire Firefox to a particular color profile. This normally is not advisable yet is worth trying temporarily if the OS is not giving the correct profile to use. Here is a cut and paste of the color configuration options in FireFox. Note that for me on my Virtual Windows machine, the profile option is left blank. If steps #1 and #2 do not work I suggest you put in the exact Folder/File path to the correct ICC profile from Spyder in this option, then save and restart Firefox. You would just double click on this option and it will open up a dialog to type in the entire file and file path:



If any of the suggested steps are taken, please retake and repost PS vs Firefox side by side and see if it makes and difference.
Fingers crossed.

 

[puppychew]

This either implies you are post processing the screen shot (another source of potential error) or that your monitor profile is incorrect and sRGB is being used as the profile (not what was set by your Spyder system).

I don't understand what post processing is.

 

[thebestcpu]

Hi Puppychew

A basic screenshot should capture the data that was sent directly to the monitor after it has gone through Color Management. For example, when I do a screenshot, the image captured is exactly the Monitor pixels data and it will include an embedded Monitor ICC profile with the data that is sent to me.

There are many ways to do screen capture included 3rd party applications. I do not know what you are using. I suppose that the screen capture could modify the captured data, convert it to sRGB (as an example) and/or shrink the size, with options of what file format to save it. On my Mac I can set a preference and mine saves it as PNG (JPEG compresses the data).

As far as post processing, one could take the screen capture and for a variety of reasons (e.g. file size), input into Photoshop, resize the image and output again (which would probably change the embedded profile as well). That is what I meant by post processing. In reality if could be done by the screen capture software of by you taking the file into PS and making some changes.

I mentioned this because you said in a prior post as taking a screen shot and using "Save-As" instead of "Save for Web". To me this implied you processed the screenshot through PS.

Hope that clarifies my thoughts.

 

[puppychew]

The way I have always done it was to do a print screen on my computer - no other software.
I then open a new file in PS and paste the image. I crop it and save it as a jpeg.
This I guess is post processing. To get an image in its native condition would be to not crop it?

The only time I do a save to web is if the image is going on my website.

Am I on the right track?

 

[puppychew]

Color management:
Laptop is monitor #1 Asus is monitor #2
Here is a screen shot for monitor 1 and 2. both list the same thing. I don't know if that is the monitor or laptop.
#1 should be the laptop right. There is no listing to choose a laptop or monitors - only printers.

The ICC profiles are names I had used when saving the calibration for the laptop and monitor.

Dropbox link

https://www.dropbox.com/sh/wxv**o1brf2z6sw/AAD3Fstr9pj4b4dIigxOMjrHa?dl=0



View attachment 56779

View attachment 56780

View attachment 56781

Post #73, #3
Firefox config - the color mgt display profile is blank. Do I need to enter a monitor path? How do I find out what the path is?

 

[thebestcpu]

Hi Puppychew

I am not an expert in Windows 7 (or Windows in general) so may be approaching my limit of usefulness.

1) Instead of using the Print Screen to the clipboard you can click on the Windows Icon and type in "Snipping Tool" in the search bar. That program should be native on your installation. You can select the portion of the window you want to capture. Then you can save it to a file directly. Unfortunately, it does not save it with a monitor profile. And since we are not sure which profile is being used for your monitor, it is probably best that you do not go through PS or other program and just post the file created from the Snipping Tool.

2) Note that in your last post the images did not appear. So I think you will need to edit that post and try again.

3) In my prior post, thought I did not say so, I wanted you to try the steps in the order given 1,2,3 and see if the PS vs Firefox image match at any of those steps.

4) The most common location for ICC profiles in Win 7 is C/Windows/System32/Spool/Drivers/Color with the specific ICC profile added after that folder path. That was for step 3 of the last post if you still cannot get a match from PS to Firefox

5) For step #2 in checking the Color Management settings under the device tab (I provided a picture), you should be able to click on the "Identify Monitor" button and a number will flash on each of your screens e.g one will have "1" and the other should have a "2". That should correspond with each being a different device in the dropdown list. The details are in the provided link. If what you see is totally different than this, then I am at the end of the road with my ability to do this through text posts. I am hoping that you will be able to determine the device in the dropdown that is associated with your 24 inch monitor and verify if the ICC profile associated with it is from your most recent calibration with your Spyder system or not. If not, it needs to be associated with this dialog box (again details in the link). Please verify where you are with this #2 step of the prior post and include screen shots. These settings need to be set correctly and then PS compared to Firefox before moving on to the step #3 of the last post. Again, if we get stuck here, then I probably cannot help with short posts given that I primarily use a Mac and you will needs a Windows expert helping possible with an online peer to peer connection to control your computer. We are trying to fix a tough color management problem at the same time you are on a steep learning curve on many fronts. That's a tough combo for forum post solutions.

7) The image data goes through a lot of hoops at many interfaces and is just a matter of tracking through each and everyone of them to get to root cause and verifying all settings are correct (i.e. no pilot error).
Fingers crossed we can hit a breakthrough as I am about at the limit of my expertise on helping via posting.

John Wheeler

 

[puppychew]

1. yes I have the snipping tool and can use that.

2. The images appear when in edit mode however I opened up a drop box account, placed the images in there and posted a link. I tried over and over again but the link does not work. When pasting the link into a tab it works fine but not in my post. Frustrating.
Here it is again https://www.dropbox.com/sh/wxv**o1brf2z6sw/AAD3Fstr9pj4b4dIigxOMjrHa?dl=0
I noticed two astericks appear in place of **.

I typed the above and astericks appeared again
4 and u should be there.

3. Yes I did them in order but again had difficulty. That is why I attached images which for some strange reason will not appear.

Before moving forward let me redo the samples.
Samples are in dropbox - just need to figure out how to let you see them.

 

[thebestcpu]

Hi Puppychew
I put the link in and replaced the "**" as you indicated and I could get access.
I will assume that you are working on updates to the images so will wait for you.
Also, in the Win 7 Color Management page under Devices Tab, I did not see a selected Spyder created profile that was selected. What is the most recent Spyder profile that was created, when did you do your last calibration to create that profile, did you find it in your list, did you verify that you Asus monitor was the #2 device and did you select the Spyder ICC profile for that monitor. I cannot tell from the screen shot you supplied.