sRGB Color Space questions

[Brian_G]

I'm sure many other people also have a problem understanding color space.

I am preparing a batch of photos to be printed commercially.

The printing company I am using (DSCL) ask that the files be submitted in sRGB color space.
When reviewing the files I note that most of them are in sRGB IEC61966-2.1 color space, which is how they were saved.
However, I have one file whose color profile is called "sRGB built-in"
What is the difference between these two sRGB profiles, and should I re-export the file with the "sRGB built-in" profile using the sRGB IEC61966-2.1 profile?

The printing company also provide a printer profile, which they ask be applied to the prints.
I can see this profile in the drop down list of profiles in the Export dialog.
Do I apply this profile by simply opening the file and then Exporting it with the printer profile I need?
If this is the case, then presumably I don't need to bother about the sRGB built-in/sRGB IEC61966-2.1 question above, since applying the printer profile will override any previous profiles, or do I need to assign the correct sRGB profile first and then assign the printer profile?

There are 12 files involved and I want to get them right first time, since if I have to have them reprinted it starts getting expensive.

[Gabe]

Hi @Brian_G,

 

You don't need to convert it twice. If you have installed the ICC profile from them already, open the image you need to work on, Click on Document>Assign ICC Profile>Assign the profile. Next, you just export as normal as the document ICC profile would be set to the one you chose earlier.

[Brian_G]

22 hours ago, GabrielM said:

Hi @Brian_G,

 

You don't need to convert it twice. If you have installed the ICC profile from them already, open the image you need to work on, Click on Document>Assign ICC Profile>Assign the profile. Next, you just export as normal as the document ICC profile would be set to the one you chose earlier.

Thanks for the reply, but I'm still a little uncertain regarding Color Space.

I currently do my raw development in Lightroom and then pass the result to Affinity Photo if I need any fine tuning.
Lightroom operates in ProPhoto Color space, which is maintained when I start working in Affinity.
When I've finished editing the ProPhoto TIFF file in Affinity, if I then save the file, it appears in the Lightroom catalog alongside the original raw file.
In order to prepare the file for printing, I assume I must then convert it to sRGB before applying the printer profile?
I cannot just apply the printer profile to the ProPhoto 16-bit TIFF file, since the printing company say they want an sRGB file with their printer profile, or does applying the printer profile also convert from TIFF to sRGB?
I previously used to do this within Lightroom, but I'm trying to break with using Adobe so I really need to understand how to create the correct print file from Affinity.

I'm also confused by the Affinity options to "Convert ICC Profile" and "Assign ICC Profile"
Should I use either of these commands, or simply apply the sRGB profile when I Export the (jpg) file?
As it is, if I "Convert ICC Profile" (to sRGB 61966) the image seems to remain the same, but if I "Assign ICC Profile" my ProPhoto image becomes washed out and desaturated.
When should one "Convert" and when should one "Assign" the ICC profile.

One final question.
In the list of available ICC profiles, I see all my monitor calibration profiles, which are obviously not required in this context.
How do I go about deleting my monitor calibration files from the list of ICC profiles?
And, more to the point, why are they appearing in the list in the first place?

[lepr]

.

 

 

[Brian_G]

Thank you for the comprehensive reply, but I think you have misunderstood my problem.

I have prepared print files many times in the past using Lightroom, which seems to be much more straightforward than Affinity.
I simply export the file as sRGB with the supplied printer profile.
My prints have always come back matching my screen image and I have been very happy with the results.
I've never done any of this "Soft proofing" malarkey, and as far as I'm concerned it's not necessary.

As I said, I'm attempting to give up using Adobe, and I want to carry out the same process using AP, which seems to be somewhat more complicated, due to the number of options offered.
Here's my workflow:
Open the edited (16-bit TIFF) file in Affinity.
At the top of the screen it says this file is "RGBA/16 ProPhoto RGB"
I have no idea what this means, but I take it to be a 16-bit RGB file in ProPhoto Color space.
I next need to convert to sRGB and export using the printer profile supplied by the printing company.
In the "Export" dialog (still in the "Photo Persona") I am presented with options to "Use document format" and "Use document profile" and I'm not used to seeing these options.
Do I select "Use document format" or change to RGB 8-bit, or does the fact that I'm converting to jpeg take care of those options?
Do I, at this stage, select sRGB as my color profile, or select the supplied printer profile?

The other option I have is to convert the image to sRGB (using "Convert ICC profile" under the "Document" drop down) and then export it.

My main problem is that I'm confused by the number of options that Affinity is offering, many of which I've never seen before.

[lepr]

.

[R C-R]

1 hour ago, Brian_G said:

I've never done any of this "Soft proofing" malarkey, and as far as I'm concerned it's not necessary.

https://www.cambridgeincolour.com/tutorials/soft-proofing.htm

https://luminous-landscape.com/understanding-soft-proofing/

https://www.slrlounge.com/soft-proofing-lightroom-adobe/

etc.

[Brian_G]

It's all very well taking my comment out of context, but you are ignoring the part above it which says:
"I have prepared print files many times in the past using Lightroom, which seems to be much more straightforward than Affinity.
I simply export the file as sRGB with the supplied printer profile.
My prints have always come back matching my screen image and I have been very happy with the results."

I'm merely trying to achieve the same result using Affinity, which offers a lot more options than I'm used to seeing.

Put simply, my question is: What settings do I use in Affinity Photo to convert a 16-bit TIFF file to an 8-bit sRGB file with a supplied printer profile?

[R C-R]

I am not trying to take anything out of context; just to make you aware of what soft proofing is (& that it is available in Lightroom as well as in Affinity Photo). As for what settings to use, there have been several suggestions about that, with & without soft proofing.

 

Whatever you decide to do, as @owenr suggested it would be a good idea to discuss this with the printing company directly.

[walt.farrell]

1 hour ago, Brian_G said:

Put simply, my question is: What settings do I use in Affinity Photo to convert a 16-bit TIFF file to an 8-bit sRGB file with a supplied printer profile?

I won't pretend to understand everything about color profiles, and maybe I'll learn something from this discussion.

But I must comment on the statement I've quoted: A file has only one color profile as far as I know, so its profile is either sRGB or it's the printer profile you want to use. I don't think it can be both.

What, exactly, have you done in the past in Lightroom with your photos, and the supplied printer profile, before you were using Affinity Photo. I don't think you've told us that, but it may provide the clues to what you need to do when using Affinity Photo.

[smadell]

Here's the thing: Walt is right. Your image file can only have a single color profile. But the phrase "color profile" is used in a few different settings, and is quite confusing. Remember that each pixel in your image is really only described by a series of 3 numbers ranging from 0 to 255. Color profiles determine the actual color that those numbers describe.

Some color profiles (like sRGB, Adobe RGB, and ProPhoto) are also described as color "spaces." They describe the breadth of colors available to an image. So, a pixel in sRGB with a numerical triplet of, say, 255,0,0 will be displayed as the most intense red that sRGB has available. But that same pixel (255,0,0) in an image using the ProPhoto color profile/space will describe an even more intense red, since ProPhoto is a wider gamut.

"Assigning" a different color profile means that you are keeping the numerical triplets the same, but are letting the new color profile set the colors. So, starting with a ProPhoto image and assigning the sRGB profile to it will always wash out the most intense colors. On the other hand, "converting" to a new profile will try to keep your colors the same, but will allow the numerical triplets to change.

Unlike color space profiles, some profiles (especially those for your monitor and those for printers) are really translations. They work in tandem with a peripheral device to keep the colors of an image reasonably constant. So, my monitor profile translates what's in my image file in order to display it properly on the screen. My printer profile translates that same file to allow my printer to print out the proper colors. If I want what I see on my monitor to match what gets printed by my printer, I need to tell my monitor to use the appropriate monitor profile, and I need to print using the appropriate printer profile.

Let's assume that you have calibrated your monitor properly. No matter what color space your image is using, you need to tell your monitor to use the monitor profile so that the image is displayed properly. In this case, your print shop is telling you that they want the image document to exist within the sRGB color space. Therefore, whatever work you do on your image, you need to CONVERT the image to the sRGB profile - either by choosing "Convert ICC Profile..." from the Document menu, or by choosing Export... from the File menu, clicking the "More" button, and choosing sRGB in the "ICC Profile" section, and making sure that "Embed Profile" is checked.

There are only 2 places where the "Printer Profile" that your print shop has supplied are going to be used. Most importantly, the print shop will use the profile when THEIR computer sends the image to THEIR printer. This printer profile will translate the color triplets in your image document into the correct colors. This is a translation that is specific to their setup. The only use that YOU have for the printer profile is to "soft proof" your image. Inside of Affinity Photo, you can Convert to sRGB profile (which will limit the gamut of colors available to your image, but which will probably not make any visible change to the image on your monitor). Then you can place a Soft Proof Adjustment layer on the top of your Layers stack, and choose the printer profile as the one being used by the adjustment. This will give you an approximation of what your eventual image will look like, given the setup that the print shop uses.

In summary, (i) convert your image to sRGB; (ii) use a Soft Proof Adjustment to check out of gamut areas (but remember to disable or remove the Soft Proof adjustment before you save/export the document); and (iii) send it off.

[Brian_G]

On 07/04/2018 at 3:45 PM, walt.farrell said:

I won't pretend to understand everything about color profiles, and maybe I'll learn something from this discussion.

But I must comment on the statement I've quoted: A file has only one color profile as far as I know, so its profile is either sRGB or it's the printer profile you want to use. I don't think it can be both.

What, exactly, have you done in the past in Lightroom with your photos, and the supplied printer profile, before you were using Affinity Photo. I don't think you've told us that, but it may provide the clues to what you need to do when using Affinity Photo.

Thanks Walt, that answers one of my questions.
I was uncertain if I needed to convert to sRGB and THEN apply the printer profile, or just to apply the printer profile.

In Lightroom part of the file export command looks like this:

So in the same menu you have the image type and the Color Space options, so under Image Format I enter JPEG and under Color Space, I enter the Printer profile (which appears on the drop down list.)
This has always worked fine. I've never "Soft proofed" and the prints come back matching what I see on my monitor screen.
What I want to do is produce the same result using Affinity, but I'm presented with a list of options that I'm not familiar with, and I want to be certain I am choosing the right settings.

 

[Brian_G]

On 07/04/2018 at 4:30 PM, smadell said:

Here's the thing: Walt is right. Your image file can only have a single color profile. But the phrase "color profile" is used in a few different settings, and is quite confusing. Remember that each pixel in your image is really only described by a series of 3 numbers ranging from 0 to 255. Color profiles determine the actual color that those numbers describe.

Some color profiles (like sRGB, Adobe RGB, and ProPhoto) are also described as color "spaces." They describe the breadth of colors available to an image. So, a pixel in sRGB with a numerical triplet of, say, 255,0,0 will be displayed as the most intense red that sRGB has available. But that same pixel (255,0,0) in an image using the ProPhoto color profile/space will describe an even more intense red, since ProPhoto is a wider gamut.

"Assigning" a different color profile means that you are keeping the numerical triplets the same, but are letting the new color profile set the colors. So, starting with a ProPhoto image and assigning the sRGB profile to it will always wash out the most intense colors. On the other hand, "converting" to a new profile will try to keep your colors the same, but will allow the numerical triplets to change.

Unlike color space profiles, some profiles (especially those for your monitor and those for printers) are really translations. They work in tandem with a peripheral device to keep the colors of an image reasonably constant. So, my monitor profile translates what's in my image file in order to display it properly on the screen. My printer profile translates that same file to allow my printer to print out the proper colors. If I want what I see on my monitor to match what gets printed by my printer, I need to tell my monitor to use the appropriate monitor profile, and I need to print using the appropriate printer profile.

Let's assume that you have calibrated your monitor properly. No matter what color space your image is using, you need to tell your monitor to use the monitor profile so that the image is displayed properly. In this case, your print shop is telling you that they want the image document to exist within the sRGB color space. Therefore, whatever work you do on your image, you need to CONVERT the image to the sRGB profile - either by choosing "Convert ICC Profile..." from the Document menu, or by choosing Export... from the File menu, clicking the "More" button, and choosing sRGB in the "ICC Profile" section, and making sure that "Embed Profile" is checked.

There are only 2 places where the "Printer Profile" that your print shop has supplied are going to be used. Most importantly, the print shop will use the profile when THEIR computer sends the image to THEIR printer. This printer profile will translate the color triplets in your image document into the correct colors. This is a translation that is specific to their setup. The only use that YOU have for the printer profile is to "soft proof" your image. Inside of Affinity Photo, you can Convert to sRGB profile (which will limit the gamut of colors available to your image, but which will probably not make any visible change to the image on your monitor). Then you can place a Soft Proof Adjustment layer on the top of your Layers stack, and choose the printer profile as the one being used by the adjustment. This will give you an approximation of what your eventual image will look like, given the setup that the print shop uses.

In summary, (i) convert your image to sRGB; (ii) use a Soft Proof Adjustment to check out of gamut areas (but remember to disable or remove the Soft Proof adjustment before you save/export the document); and (iii) send it off.

Thanks very much for the lengthy reply.

I think one of the reasons I'm a little confused is because AP offers many more options than I'm used to seeing, so I'm unsure exactly which to choose.
This is exacerbated by me having experimented with different settings and become even more confused.
I recently created a file to use in a club projected image competition, and when shown it was very desaturated, so I think I must have left it in ProPhoto color space instead of converting it to sRGB, which is what our club projector requires.

The printing company ask that the print files are submitted to them with their printer profile attached, which is what I've done in the past and received excellent results.
As I've said previously, I've never "Soft Proofed" and always thought it was a process for those who print their own images.

With all the advice and suggestions, I think I'm now ready to send off some files for printing, so thank you every one for the help information.

 

[Woodkopf]

Apologies for late response, (playing catchup).

On the DScolour Labs Technical Support webpage is a "Step by Step guide to Editing your image" (- http://dscolourlabs.co.uk/about/Technical_Support), which suggests photos should be edited in sRGB colour working space, softproofed using their Lustre or Gloss profiles, (which can be downloaded & installed).  Then if you are happy with the result, to select the appropriate colour profile using "Edit/Convert to Profile".

However at http://dscolourlabs.co.uk/about/NEWNEW_Technical_Support, they 'DSC' state "DON'T FORGET TO SAVE YOUR IMAGE IN sRGB AND USE THE CORRECT PAPER PROFILE IF REQUIRED."  Which I find confusing.