Color management in Photoshop

[Mare333]

Hello,
Marianne here. It's nice to meet my fellow photographers and I am really glad I found this forum. Today I hope you can help me out with a question. I have just purchased a monitor and calibrated and profiled it with the enclosed software. So now I have an ICC profile for my monitor. My question, however is about color management IN PHOTOSHOP. I see this term color management IN PHOTOHSOP thrown around all the time on the web, but what does it actually refer to? They say that Photoshop is color managed software, but do we ACTUALLY need to do anything to color manage IN PHOTOSHOP or does the software just do its thing? For example when we are editing and saving the image IN PHOTOSHOP do we ACTUALLY need to do anything to color manage it? Also the ICC profile that I created for the monitor, where does that fit into the picture? Do I need to do anything IN PHOTOSHOP to use this ICC profile or as long as I know my monitor is using this ICC profile displaying the colors according to this ICC profile I don't have to do anything else IN PHOTOSHOP? What I am most interested in is making sure the way I see the image shown on the screen will be the same as the print looks or at least close to it. To my understanding that's what color management is for. As you can see I am pretty confused, I would really appreciate if you shed some light on this subject for me. Thank you very much for your help.

[Manfred M]

Hello,
Marianne here. It's nice to meet my fellow photographers and I am really glad I found this forum. Today I hope you can help me out with a question. I have just purchased a monitor and calibrated and profiled it with the enclosed software. So now I have an ICC profile for my monitor. My question, however is about color management IN PHOTOSHOP. I see this term color management IN PHOTOHSOP thrown around all the time on the web, but what does it actually refer to? They say that Photoshop is color managed software, but do we ACTUALLY need to do anything to color manage IN PHOTOSHOP or does the software just do its thing? For example when we are editing and saving the image IN PHOTOSHOP do we ACTUALLY need to do anything to color manage it? Also the ICC profile that I created for the monitor, where does that fit into the picture? Do I need to do anything IN PHOTOSHOP to use this ICC profile or as long as I know my monitor is using this ICC profile displaying the colors according to this ICC profile I don't have to do anything else IN PHOTOSHOP? What I am most interested in is making sure the way I see the image shown on the screen will be the same as the print looks or at least close to it. To my understanding that's what color management is for. As you can see I am pretty confused, I would really appreciate if you shed some light on this subject for me. Thank you very much for your help.

Welcome to CiC Marianne. Would you mind clicking on the "My Profile" button on the top of the page and entering at least your first name and where you are from?

When you say you have created a profile of your computer screen with the software that shipped with your computer screen, can I assume it is both a hardware PLUS software solution, i.e. there is a device that is placed on your computer screen that works with the software to create a profile? These devices are generally produced by either x-Rite or DataColor.

When we write about "Colour Management", what we are really discussing is coming up with a way to ensure that each device from camera to computer screen to printer show the colour accurately. This is a fairly complex and somewhat finicky process, but if do things correctly, you can be reasonably confident this is happening properly.

In some ways the computer screen is the weakest link in the entire colour managed workflow. Before it can be colour managed, it has to be able to accurately reproduce colours and that is something the screen's manufacturer has to tell us unless one has access to some sophisticated electronic measurement tools. Unless your computer screen says it is 100% sRGB or close to 100% AdobeRGB compliant, you profiling and calibration operations are not necessarily meaningful.

There are two important and independent aspects of setting a computer screen. The first is ensuring that it has been set up to appropriate brightness and contrast levels. Normally for photographic work, one is looking for output in the 80 candela / square meter to 120 candela / square meter range. The underlying assumption is that your workspace is also adequately lit. For most photo editing work, one is looking at a slightly darkened room with a maximum light level at the work area of less than 70 lux.

The second part of this operation is to measure the actual colours that your screen reproduces against a set standard using either a photospectrometer or colorimeter (one of the devices I mentioned previously). The software writes this all into a colour lookup table that your computer operating system loads when it starts up.

The final step is when one prints (if one prints). Photo printers (and the associated inks) and papers will have colour profiles that continue the colour managed workflow, to ensure that the process continues. These profiles ensure that the colour information is correct and the print comes out as close as possible to what you see on the computer screen. These will never be exactly the same as the computer screen is an transmitted light, additive colour, RGB workflow while the printer uses a reflected light, subtractive colour, CMYK workflow.

This is the "simplified" explanation and I hope it makes some sense to you.

[DanK]

Marianne,

This site has a large number of tutorials. There is an entire page of tutorials explaining various aspects of color management at this link: https://www.cambridgeincolour.com/co...t-printing.htm. It probably has more detail than you want, but it would be worth your looking it over.

Dan

[dje]

Marianne the display colour management process is basically handled automatically between Photoshop and the computer's Operating System. If you are using Windows, you can check what monitor profile is being used by going into the Colour Management tab on the Control Panel.



To get this screen open, hit Windows key+R which opens up the run dialogue. In here type in Control Panel and hit enter. Then select Colour management from the Control Panel. Then select your monitor from the device list.

If the profile you created is shown here as the default, it is the one that will be used normally.

I imagine a similar process applies to a Mac but I'm not familiar with that system.

Dave

[Mare333]

Welcome to CiC Marianne. Would you mind clicking on the "My Profile" button on the top of the page and entering at least your first name and where you are from?

When you say you have created a profile of your computer screen with the software that shipped with your computer screen, can I assume it is both a hardware PLUS software solution, i.e. there is a device that is placed on your computer screen that works with the software to create a profile? These devices are generally produced by either x-Rite or DataColor.

When we write about "Colour Management", what we are really discussing is coming up with a way to ensure that each device from camera to computer screen to printer show the colour accurately. This is a fairly complex and somewhat finicky process, but if do things correctly, you can be reasonably confident this is happening properly.

In some ways the computer screen is the weakest link in the entire colour managed workflow. Before it can be colour managed, it has to be able to accurately reproduce colours and that is something the screen's manufacturer has to tell us unless one has access to some sophisticated electronic measurement tools. Unless your computer screen says it is 100% sRGB or close to 100% AdobeRGB compliant, you profiling and calibration operations are not necessarily meaningful.

There are two important and independent aspects of setting a computer screen. The first is ensuring that it has been set up to appropriate brightness and contrast levels. Normally for photographic work, one is looking for output in the 80 candela / square meter to 120 candela / square meter range. The underlying assumption is that your workspace is also adequately lit. For most photo editing work, one is looking at a slightly darkened room with a maximum light level at the work area of less than 70 lux.

The second part of this operation is to measure the actual colours that your screen reproduces against a set standard using either a photospectrometer or colorimeter (one of the devices I mentioned previously). The software writes this all into a colour lookup table that your computer operating system loads when it starts up.

The final step is when one prints (if one prints). Photo printers (and the associated inks) and papers will have colour profiles that continue the colour managed workflow, to ensure that the process continues. These profiles ensure that the colour information is correct and the print comes out as close as possible to what you see on the computer screen. These will never be exactly the same as the computer screen is an transmitted light, additive colour, RGB workflow while the printer uses a reflected light, subtractive colour, CMYK workflow.

This is the "simplified" explanation and I hope it makes some sense to you.

Thank you for your explanation, it totally makes sense You are right I calibrated not only with the software but with a colorimeter. Also my monitor is wide gamut so it INDEED SAYS 99%RGB, 100%sRGB. I got a lot of links about color management. Will read through them and if I still have questions I'll be back to ask them, hopefully I won't need to P.S. I entered my name and location into my profile as you asked me to. Thanks again

[Mare333]

Marianne,

This site has a large number of tutorials. There is an entire page of tutorials explaining various aspects of color management at this link: https://www.cambridgeincolour.com/co...t-printing.htm. It probably has more detail than you want, but it would be worth your looking it over.

Dan

Thank you for letting me know, I will look into it

[Mare333]

Marianne the display colour management process is basically handled automatically between Photoshop and the computer's Operating System. If you are using Windows, you can check what monitor profile is being used by going into the Colour Management tab on the Control Panel.



To get this screen open, hit Windows key+R which opens up the run dialogue. In here type in Control Panel and hit enter. Then select Colour management from the Control Panel. Then select your monitor from the device list.

If the profile you created is shown here as the default, it is the one that will be used normally.

I imagine a similar process applies to a Mac but I'm not familiar with that system.

Dave

Thank you very much for your reply, this information was really helpful.

[Rufus]

The OP was essentially asking whether, having calibrated the screen, there was anything we need to do in Photoshop itself to ensure that colour is managed throughout the workflow. From the other posts is seems the answer is no. We need to calibrate the screen and the printer, but there is nothing to be done in Photoshop. So far as I can tell the only exception is that in Photoshop we might need to consider the sRGB / Adobe RGB options. Personally my current default position is to go for sRGB throughout but that may just reflect a lack of understanding on my part.


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[Mare333]

The OP was essentially asking whether, having calibrated the screen, there was anything we need to do in Photoshop itself to ensure that colour is managed throughout the workflow. From the other posts is seems the answer is no. We need to calibrate the screen and the printer, but there is nothing to be done in Photoshop. So far as I can tell the only exception is that in Photoshop we might need to consider the sRGB / Adobe RGB options. Personally my current default position is to go for sRGB throughout but that may just reflect a lack of understanding on my part.


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Thank you for understanding EXACTLY what I was asking about. And from what I gather from the replies as well the answer is NO.

[pschlute]

Thank you for understanding EXACTLY what I was asking about. And from what I gather from the replies as well the answer is NO.

There are some settings in Photoshop which will affect how your image is viewed and processed.

under Edit/Color settings you can choose your working colour space. I have mine set to Adobe RGB (I too have a wide gamut monitor).

In the same menu there is a tick box for profile mismatches. I have mine set to "Ask when opening".

Another important menu item is edit/Convert to profile. Here the destination colour space is important. If you are editing an image in Adobe RGB for example and want your final image to be displayed on the internet you need to convert your image to sRGB, otherwise your colours will be wrong to anyone viewing them on an unmanaged browser.

Also you want to try and ensure your internet browser is colour managed. This link is quite old, but I found it useful http://www.gballard.net/psd/go_live_...Gprofiles.html

[Manfred M]

The OP was essentially asking whether, having calibrated the screen, there was anything we need to do in Photoshop itself to ensure that colour is managed throughout the workflow. From the other posts is seems the answer is no. We need to calibrate the screen and the printer, but there is nothing to be done in Photoshop. So far as I can tell the only exception is that in Photoshop we might need to consider the sRGB / Adobe RGB options. Personally my current default position is to go for sRGB throughout but that may just reflect a lack of understanding on my part.


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Let me disagree with you here, especially on the print side. No additional steps have to be taken with respect to the screen (sort of), but if one is printing, the appropriate paper / printer profiles have to be installed on the computer (via the paper manufacturer's website) and the correct profile and rendering intent have to be selected when printing.

The Photoshop print settings have to be input; Printer selection (if there is more than one printer), Color Management(Color Handling, Printer Profile, Rendering Intent and Black Point Compensation all need to be set). There will also be some printer settings that have to be handled via the Print Settings box; I can't go into specifics here, as each printer will have a different interface. When printing in colour, the printer's internal colour management must be disabled, otherwise the colour managed data from Photoshop will not be used by the printer.

When starting a new edit the user needs to set the colour mode (RGB), but depth (16 bits) and Colour Profile (when printing at least Adobe RGB, usually ProPhoto RGB and NEVER sRGB). Modern photo printers have wider gamuts than even the best computer screens and exceed the Adobe RGB colour space capabilities, especially with high Dmax papers.

[xpatUSA]

There are some settings in Photoshop which will affect how your image is viewed and processed.

under Edit/Color settings you can choose your working colour space. I have mine set to Adobe RGB (I too have a wide gamut monitor).

In the same menu there is a tick box for profile mismatches. I have mine set to "Ask when opening".

Another important menu item is edit/Convert to profile. Here the destination colour space is important. If you are editing an image in Adobe RGB for example and want your final image to be displayed on the internet you need to convert your image to sRGB, otherwise your colours will be wrong to anyone viewing them on an un-managed browser.

I remember those options from Elements 6! Never understood them back then ...

I was curious about rendering intent in Adobe conversions and found this:

https://help.adobe.com/en_US/creativ...5-A5C35BCEDF67

It seems that Adobe's default (USA, UK) rendering intent is Relative Colorimetric *. If that is so after editing in Adobe RGB (1998) working space, color-gamut-clipping is possible during conversion to sRGB.

https://www.cambridgeincolour.com/tu...conversion.htm

* For some reason, it's 'Perceptual' in Japan.

[Rufus]

I used sloppy terminology in relation to calibrating the printer, Manfred. I need not explain further other than to confess that a little knowledge is a dangerous thing in my hands.

Your comprehensive post 11 adds significantly to the earlier discussion and will hopefully help the OP. I think we are teasing out the information she was seeking.

I am currently trying to get a better understanding of what all these items in the PS Print Settings dialogue box mean and which options I should select. This thread and the one about the pink tint to B&W prints are certainly helping with that.



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[Mare333]

There are some settings in Photoshop which will affect how your image is viewed and processed.

under Edit/Color settings you can choose your working colour space. I have mine set to Adobe RGB (I too have a wide gamut monitor).

In the same menu there is a tick box for profile mismatches. I have mine set to "Ask when opening".

Another important menu item is edit/Convert to profile. Here the destination colour space is important. If you are editing an image in Adobe RGB for example and want your final image to be displayed on the internet you need to convert your image to sRGB, otherwise your colours will be wrong to anyone viewing them on an unmanaged browser.

Also you want to try and ensure your internet browser is colour managed. This link is quite old, but I found it useful http://www.gballard.net/psd/go_live_...Gprofiles.html

Hi, thank you fro your reply. I have watched a few tutorials and now have a much better understanding of the Color Settings and Convert to profile functions in Photoshop. Question - you mention if we have and Adobe RGB file but need an image for the web we convert it to sRGB so that's fine, but can we do it THE OTHER WAY AROUND i.e. if we start with an sRGB image can we convert it to Adobe RGB since Adobe RGB has MORE colors than sRGB? Thanks again for your help and hope you can answer my question.

[Manfred M]

if we start with an sRGB image can we convert it to Adobe RGB since Adobe RGB has MORE colors than sRGB? Thanks again for your help and hope you can answer my question.

No; it is a "one-way" operation only. When one down samples to a smaller colour space, those colours disappear. Upsampling simply maps the colour data from the smaller colour space to the larger one, but there is no more colour information.

As a general rule, working in the largest colour space is best because it has the most colour data. My default colour space is ProPhoto, which covers around 90% of the colours that humans can see. Adobe RGB covers around half of the colours humans see and sRGB is around one third of the colours.

[Mare333]

No; it is a "one-way" operation only. When one down samples to a smaller colour space, those colours disappear. Upsampling simply maps the colour data from the smaller colour space to the larger one, but there is no more colour information.

As a general rule, working in the largest colour space is best because it has the most colour data. My default colour space is ProPhoto, which covers around 90% of the colours that humans can see. Adobe RGB covers around half of the colours humans see and sRGB is around one third of the colours.

That makes sense, thank you so much for your help

[george013]

No; it is a "one-way" operation only. When one down samples to a smaller colour space, those colours disappear. Upsampling simply maps the colour data from the smaller colour space to the larger one, but there is no more colour information.

As a general rule, working in the largest colour space is best because it has the most colour data. My default colour space is ProPhoto, which covers around 90% of the colours that humans can see. Adobe RGB covers around half of the colours humans see and sRGB is around one third of the colours.

We've discussed this before. It still doesn't make sense to me. There're mathematical formulas to transfer from Adobe RGB to sRGB. And mostly mathematical formulas can be inverted.
The sensor collects light through its color filters. Those values will be digitized. In the raw converter the pixel values will be created, RGB values with a correction to the wanted color space.
If you look at that horseshoe you'll see that the analogue range of green is much bigger in Adobe RGB as in sRGB. It looks to me that if you correct those digital values for the other color space you're done.
This writing is just out of my thumb.
How do you get to ProPhoto?

George

[DanK]

And mostly mathematical formulas can be inverted.

No, functions can be inverted, but many mathematical formulas cannot be. The key is whether there is a 1:1 mapping from input to output, as there is in the case of all functions (by definition). Any transformation that results in two or more input values mapping to a single output value cannot be reversed because data has been lost.

I don't know the actual equations, but I think, perceptual and relative colorimetric rendering illustrates this. If I am right, perceptual rendering works by compressing the distribution of color values so that none fall out of gamut. That should be reversible. Relative works by censoring the distribution, transforming out-of-gamut values to in-gamut but leaving the already in-gamut pixels unchanged. That would not be reversible.

[xpatUSA]

As a general rule, working in the largest colour space is best because it has the most colour data.

Not for me, Manfred. I shoot a lot of flowers which have well-saturated colors. If I edit in ProPhoto working-space and make them look really "pretty" * in the review image - and then save as sRGB, gamut-clipping is almost inevitable. An illustration of that in photographic fora is the common occurrence of red flower posts with funny-looking purple areas on the petals which, on examination, have no green in them at all.

* No clipped or bottomed channels in the working-space color-picker.

Which is why I personally use sRGB working-space - because that is what my output is and any gamut problems are immediately shown on my screen.

Not saying you're wrong, only saying that a ProPhoto working-space is not perfect for all workflows ... which is what I hope you meant by "general rule".

[xpatUSA]

If you look at that horseshoe you'll see that the analogue range of green is much bigger in Adobe RGB (1998) [than] in sRGB.

Not that much bigger, George: in "that horseshoe" (CIE xyY 1931 diagram) the range of green is exaggerated perceptually. If you look in the perceptually-equal CIELUV or CIELAB diagrams, the difference is much smaller.