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Author Topic: Unexpected result after converting image profile to softproof profile  (Read 8174 times)

walter.sk

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I have been processing and preparing image files to upload to Costco for my wife, and ran into a problem.  Here is my workflow in Photoshop CC 2018 and Lightroom Classic:

1) I optimize the raw file in LR, then edit it in PS, and save it as a Tiff.
2) After opening the edited tiff again in LR, I softproof it using the downloaded Costco profile for the Fuji Frontier with Luster paper, making the softproofed version a Proof Copy, adjusted to look as close to the original Tiff as possible.
3) I send the Proof Copy back to Photoshop, where I make the canvas about 2% bigger so that when Costco makes the image a bit larger for full bleed I don't lose any of the actual image I want.  I then switch from 16-bit to 8-bit, and Convert to Profile from Prophoto to the Costco profile.

While I did this with two files last week, and they were printed by Costco and came out fine after specifying "No Automatic Corrections," or whatever the actual term is, I repeated what I thought was the same procedure this week, with horrible results, looking way oversaturated and as if I somehow had double profiled them.

The question is, if I softproof an image in LR using the Costco profile, and adjust it to best resemble the original, and then convert the image to the Costco profile, is this actually causing a problem such as double profiling?
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Mark D Segal

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Re: Unexpected result after converting image profile to softproof profile
« Reply #1 on: March 21, 2018, 07:27:48 PM »

I don't believe you are double profiling with the procedure described in your last sentence. The softproof happens in the Develop Module using the Costco profile as the device being simulated. It isn't doing anything to your image file; it is only simulating your edits within that space; presumably you have paper white and black ink being simulated with the Costco profile. When you export the edited file from Lr I assume you have that Costco profile embedded. Then you bring it to Costco asking them to print it without adjusting anything, right? I think that's where the problem starts and perhaps first thing is that you need to have a conversation with them asking them exactly what they did.
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Mark D Segal (formerly MarkDS)
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walter.sk

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Re: Unexpected result after converting image profile to softproof profile
« Reply #2 on: March 21, 2018, 08:27:41 PM »

...Then you bring it to Costco asking them to print it without adjusting anything, right? I think that's where the problem starts and perhaps first thing is that you need to have a conversation with them asking them exactly what they did.
Fortunately, I didn't have them print it.  I just uploaded the file to my wife's "album" and clicked on the image to view it.  It was horrible.  I checked her account preferences, and she has set as a default "Auto Correct Off."  I opened the same file in LR and it was garish, although it did look a lot more reasonable when I checked the Softproof box again.

I dunno...maybe I was over-aggressive when doing the softproof optimization.  However, I've been softproofing for many years and printing myself, and haven't run into this phenomenon, at least in this century!
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Mark D Segal

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Re: Unexpected result after converting image profile to softproof profile
« Reply #3 on: March 21, 2018, 08:47:15 PM »

Ahah - the Costco profile is probably a smaller colour space than Lr's working space, so when you first put it under soft-proof you probably ramped-up stuff like Clarity and Vibrance to better simulate what it looked like without softproof. So then if you turn softproof OFF with those adjustments done, the non-softproofed version should look hyped, because you intentionally hyped it. No problem there.
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Mark D Segal (formerly MarkDS)
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walter.sk

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Re: Unexpected result after converting image profile to softproof profile
« Reply #4 on: March 21, 2018, 10:04:08 PM »

Hmmm...

I'm going to have them do a test print and see what happens.  Maybe the way to go would be to convert to sRGB and 8 bits, and then convert to the Costco profile.  That may be what I did last week when it seemed to work OK.
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Mark D Segal

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Re: Unexpected result after converting image profile to softproof profile
« Reply #5 on: March 21, 2018, 10:11:22 PM »

Actually I was in the back of my mind wondering about a working space mismatch (because I remember from my scanning days that SilverFast performed better in aRGB(98) than in ProPhoto), but then thought perhaps the embedding of the Costco profile should over-ride this. Maybe not - I forget. Why not give them two versions - one worked-up in ProPhoto and the other in sRGB, both with the Costco profile embedded and see how they compare after printing.
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Mark D Segal (formerly MarkDS)
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Doug Gray

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Re: Unexpected result after converting image profile to softproof profile
« Reply #6 on: March 21, 2018, 10:30:02 PM »

Hmmm...

I'm going to have them do a test print and see what happens.  Maybe the way to go would be to convert to sRGB and 8 bits, and then convert to the Costco profile.  That may be what I did last week when it seemed to work OK.
I wouldn't do that. Especially if your original image is in a larger gamut like Adobe or ProPhoto RGB. You would be likely to clip the more saturated colors and get bad results.

I don't use Lightroom for conversion to Costco Profiles. But this process works whether you convert to the printer's profile with either Photoshop or Lightroom.

Give an image tagged in a Costco (or any other) printer's RGB space:

If you want to check how an image will look when printed then, from Photoshop, convert the image you would send to Costco and is tagged with the Costco profile, to a standard colorspace recognized by whatever app your wife is using. Usually they can handle standard RGB profiles.

Do it like this: From the tagged Costco image, convert to ProPhoto if the app can handle ProPhoto, otherwise sRGB using Colorimetric without selecting BPC. Important. Don't select BPC here. This produces what is, in effect, a soft proof image of what Costco should print, adapted to the display white point. Looking at it is the same as viewing a soft proof but without showing paper color and should give a good match to what Costco prints when sending the Costco tagged to Costco printers w/o color management per DryCreek's instructions.
« Last Edit: March 21, 2018, 10:48:52 PM by Doug Gray »
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walter.sk

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Re: Unexpected result after converting image profile to softproof profile
« Reply #7 on: March 22, 2018, 09:40:48 AM »

Do it like this: From the tagged Costco image, convert to ProPhoto if the app can handle ProPhoto, otherwise sRGB using Colorimetric without selecting BPC. Important. Don't select BPC here. This produces what is, in effect, a soft proof image of what Costco should print, adapted to the display white point. Looking at it is the same as viewing a soft proof but without showing paper color and should give a good match to what Costco prints when sending the Costco tagged to Costco printers w/o color management per DryCreek's instructions.
Sounds like a plan!  I printed this out and will try it.....
I tried it and need to ask:  did you mean Relative Colorimetric or Absolute Colorimetric?
« Last Edit: March 22, 2018, 10:09:30 AM by walter.sk »
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Rand47

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Re: Unexpected result after converting image profile to softproof profile
« Reply #8 on: March 22, 2018, 10:00:15 AM »

Actually I was in the back of my mind wondering about a working space mismatch (because I remember from my scanning days that SilverFast performed better in aRGB(98) than in ProPhoto), but then thought perhaps the embedding of the Costco profile should over-ride this. Maybe not - I forget. Why not give them two versions - one worked-up in ProPhoto and the other in sRGB, both with the Costco profile embedded and see how they compare after printing.

I’ve been following this thread with much interest.  Since I do all my own printing, exporting files for printing at a lab is something I don’t understand well.  Andrew Rodney helped me in another thread quite a bit, BUT in following this thread I find myself confused.  “Embed, convert, tag . . . “. Are these synonyms?  I think I understand well the soft proofing using Costco’s ICC profile.  (We’re talking LR Classic CC here.)  Now I’m ready to export the soft proofed version of the file from LR so that I can take (or upload) to Costco for printing.  What EXACTLY do I do in the export dialog in LR with the file?  Convert, embed, tag... with Costco’s ICC profile - what the heck does this mean?  I feel like there’s a huge hole in my understanding and would be very grateful for some education here.  Thanks in advance for any help in getting me straightened out.  Apologies to the OP for hitch-hicking on the thread.

Rand
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Mark D Segal

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Re: Unexpected result after converting image profile to softproof profile
« Reply #9 on: March 22, 2018, 10:19:34 AM »

I’ve been following this thread with much interest.  Since I do all my own printing, exporting files for printing at a lab is something I don’t understand well.  Andrew Rodney helped me in another thread quite a bit, BUT in following this thread I find myself confused.  “Embed, convert, tag . . . “. Are these synonyms?  I think I understand well the soft proofing using Costco’s ICC profile.  (We’re talking LR Classic CC here.)  Now I’m ready to export the soft proofed version of the file from LR so that I can take (or upload) to Costco for printing.  What EXACTLY do I do in the export dialog in LR with the file?  Convert, embed, tag... with Costco’s ICC profile - what the heck does this mean?  I feel like there’s a huge hole in my understanding and would be very grateful for some education here.  Thanks in advance for any help in getting me straightened out.  Apologies to the OP for hitch-hicking on the thread.

Rand

Yes, it's easy to get confused with jargon so don't be too hard on yourself. 

Now my understanding: specifically in Lr, when you export a raw file using CMD-SHIFT-E (if you are on Mac) CTRL-SHIFT-E (Windows), you can select in the File Settings Section for the Color Space what profile to include with the photo so that the onward processing device (in this case a Costco printer) will know how to interpret the colours. So you select the Costco profile and once exported the file will have the Costco profile embedded. But then the photo is purposed to that one onward processing option: the Costco printer.

The more flexible approach would be to export it in either ProPhoto or ARGB(98) depending on how much gamut the image needs, then open it in Photoshop and in the Edit menu go to Assign and assign the profile corresponding to the output process that will then handle the Photo. You can always go back and re-assign any other profile for another purpose afterward. By assigning a profile, the image is "tagged" with this profile and the onward process knows how to interpret the file colour values.
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Mark D Segal (formerly MarkDS)
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Doug Gray

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Re: Unexpected result after converting image profile to softproof profile
« Reply #10 on: March 22, 2018, 10:44:20 AM »

Sounds like a plan!  I printed this out and will try it.....
I tried it and need to ask:  did you mean Relative Colorimetric or Absolute Colorimetric?
Relative intent. It makes the whites match.

Warning. When you convert an image to a printer/paper profile, how it looks depends on the settings and assumptions of the application. This is because the image does not carry information about how the image was converted but only the raw rgb values that would go to the printer. This can be pretty wrong depending on assumptions the application makes about what options to choose to interpret the device rgb values. To see how the image, when printed, will actually look, you have to first convert it back to a "regular" rgb colorspace using either Relative Colorimetric without selecting BPC or Absolute Colorimetric.  Absolute will decrease the brightness in an attempt to show the actual paper color when printed which is usually shifted somewhat in tint and reduced in brightness because paper cannot go all the way to L*=100.
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Rand47

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Re: Unexpected result after converting image profile to softproof profile
« Reply #11 on: March 22, 2018, 10:54:27 AM »

Yes, it's easy to get confused with jargon so don't be too hard on yourself. 

Now my understanding: specifically in Lr, when you export a raw file using CMD-SHIFT-E (if you are on Mac) CTRL-SHIFT-E (Windows), you can select in the File Settings Section for the Color Space what profile to include with the photo so that the onward processing device (in this case a Costco printer) will know how to interpret the colours. So you select the Costco profile and once exported the file will have the Costco profile embedded. But then the photo is purposed to that one onward processing option: the Costco printer.

The more flexible approach would be to export it in either ProPhoto or ARGB(98) depending on how much gamut the image needs, then open it in Photoshop and in the Edit menu go to Assign and assign the profile corresponding to the output process that will then handle the Photo. You can always go back and re-assign any other profile for another purpose afterward. By assigning a profile, the image is "tagged" with this profile and the onward process knows how to interpret the file colour values.

Mark,

Thanks a ton!  The “Ah ha!” light has come on.  The bit I was missing was the Photoshop step and “assign” =‘s “tagged” concept.  For my purposes, the LR export method will be better, as I will just keep those files separated out from my LR catalog and re-named for easy ID.  But for sharing w/ others in the camera club, this fuller explanation is also VERY helpful.  Thanks again . . .

Rand
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Doug Gray

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Re: Unexpected result after converting image profile to softproof profile
« Reply #12 on: March 22, 2018, 11:10:01 AM »

Yes, it's easy to get confused with jargon so don't be too hard on yourself. 

Now my understanding: specifically in Lr, when you export a raw file using CMD-SHIFT-E (if you are on Mac) CTRL-SHIFT-E (Windows), you can select in the File Settings Section for the Color Space what profile to include with the photo so that the onward processing device (in this case a Costco printer) will know how to interpret the colours. So you select the Costco profile and once exported the file will have the Costco profile embedded. But then the photo is purposed to that one onward processing option: the Costco printer.

The more flexible approach would be to export it in either ProPhoto or ARGB(98) depending on how much gamut the image needs, then open it in Photoshop and in the Edit menu go to Assign and assign the profile corresponding to the output process that will then handle the Photo. You can always go back and re-assign any other profile for another purpose afterward. By assigning a profile, the image is "tagged" with this profile and the onward process knows how to interpret the file colour values.

I don't believe that's correct. If the exported image was in a regular RGB space you would want to convert it, not assign it. Assigning the image to the printer colorspace just tells the application to interpret the RGB values as printer space RGB values and they can be quite different colors. The only reason ever to assign, vs convert, is when the image is untagged and you know what the tag should be, or when the image tag is incorrect. The latter sometimes occurs when importing an untagged image which is automatically tagged on import. Otherwise one shouldn't assign a colorspace.

General rule. Anytime you find yourself in the Assign->Assign Colorspace menu stop and ask yourself why? Is this really what you want. It rarely is.
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digitaldog

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Re: Unexpected result after converting image profile to softproof profile
« Reply #13 on: March 22, 2018, 11:43:39 AM »

Hmmm...

I'm going to have them do a test print and see what happens.  Maybe the way to go would be to convert to sRGB and 8 bits, and then convert to the Costco profile.  That may be what I did last week when it seemed to work OK.
NO, don't do that. Pointless and only useful to clip colors you possibly produced and can output (but maybe NOT see on-screen).
See:

The benefits of wide gamut working spaces on printed output:

This three part, 32 minute video covers why a wide gamut RGB working space like ProPhoto RGB can produce superior quality output to print.

Part 1 discusses how the supplied Gamut Test File was created and shows two prints output to an Epson 3880 using ProPhoto RGB and sRGB, how the deficiencies of sRGB gamut affects final output quality. Part 1 discusses what to look for on your own prints in terms of better color output. It also covers Photoshop’s Assign Profile command and how wide gamut spaces mishandled produce dull or over saturated colors due to user error.

Part 2 goes into detail about how to print two versions of the properly converted Gamut Test File  file in Photoshop using Photoshop’s Print command to correctly setup the test files for output. It covers the Convert to Profile command for preparing test files for output to a lab.

Part 3 goes into color theory and illustrates why a wide gamut space produces not only move vibrant and saturated color but detail and color separation compared to a small gamut working space like sRGB.

High Resolution Video: http://digitaldog.net/files/WideGamutPrintVideo.mov
Low Resolution (YouTube): https://www.youtube.com/watch?v=vLlr7wpAZKs&feature=youtu.be
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digitaldog

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Re: Unexpected result after converting image profile to softproof profile
« Reply #14 on: March 22, 2018, 11:45:50 AM »

“Embed, convert, tag . . . “. Are these synonyms? 
No. Embed and tag mean the same thing; place the actual ICC profile inside the document to define it's color space. If you use the Assign Profile command in Photoshop as an example, you tag the document with that new profile. The profile is embedded and saved inside the document. If you convert from say sRGB (ugh no!) to a printer output color space, the data does change from one color space to the other and, the output color space in this case, the printer profile, gets embedded (tagged) in this document.


BIG difference between Assign and Convert!

Photoshop CC's Color Settings & the Convert to Profile and Assign Profile command.
This new video covers everything you thought you wanted to know about the Photoshop Color Setting dialog. It also discusses the Convert to Profile Command and the Assign Profile Command. Photoshop CC 2017 is used in this video and it updates the video on this subject I Published on June 28, 2012.

High Rez: http://digitaldog.net/files/PhotoshopColorSettings.mp4
Low Rez (YouTube): https://www.youtube.com/watch?v=6JaHOGDK5OI
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Mark D Segal

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Re: Unexpected result after converting image profile to softproof profile
« Reply #15 on: March 22, 2018, 05:20:50 PM »

I don't believe that's correct. If the exported image was in a regular RGB space you would want to convert it, not assign it. Assigning the image to the printer colorspace just tells the application to interpret the RGB values as printer space RGB values and they can be quite different colors. The only reason ever to assign, vs convert, is when the image is untagged and you know what the tag should be, or when the image tag is incorrect. The latter sometimes occurs when importing an untagged image which is automatically tagged on import. Otherwise one shouldn't assign a colorspace.

General rule. Anytime you find yourself in the Assign->Assign Colorspace menu stop and ask yourself why? Is this really what you want. It rarely is.

I'm not so sure about this. The context here is dealing with a service bureau or external photo processor. To prepare photos for these outfits you would anyhow softproof your file with their profile (if they are serious enough to give it to you) so that what comes out of their process is what you expect. So then remains the question of what you send them. This depends on their instructions. If they tell you they want the photos in sRGB or ARGB(98), that means their process will tag the image with their output profile for printing. If they tell you to assign their printer profile, that means they are expecting to receive a print-ready file that they don't need to do anything with other than process it. I've never seen instructions in this context asking people to Convert.
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Mark D Segal (formerly MarkDS)
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Doug Gray

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Re: Unexpected result after converting image profile to softproof profile
« Reply #16 on: March 22, 2018, 05:42:13 PM »

I'm not so sure about this. The context here is dealing with a service bureau or external photo processor. To prepare photos for these outfits you would anyhow softproof your file with their profile (if they are serious enough to give it to you) so that what comes out of their process is what you expect. So then remains the question of what you send them. This depends on their instructions. If they tell you they want the photos in sRGB or ARGB(98), that means their process will tag the image with their output profile for printing. If they tell you to assign their printer profile, that means they are expecting to receive a print-ready file that they don't need to do anything with other than process it. I've never seen instructions in this context asking people to Convert.

Mark,
This is true for most all external processors that expect sRGB or Adobe RGB but Costco is a different critter. They allow you to send them RGB images in device space. So conversion to device space using whatever options are desired (Perc. Rel. Col, BPC, Saturation, or even Abs. Col.) is done by the customer and the converted file is uploaded along with instructions not to do auto adjustments. DryCreek has extensive instructions on how to do this and maintains a database of profiles for a variety of locations and printers Costco uses. It provides customers an unusual level of control for those that choose to use it.

https://www.drycreekphoto.com/icc/index.html

That said, I can't imagine a print vendor asking to assign an image created in a standard RGB space to a printer's profile. That would usually produce bad results.

To further expand on why assigning a printer profile to an sRGB image is bad, there exists no printer than can print the sRGB gamut, let alone the large number of printable colors outside of sRGB which would presumably be clipped. The only way it would begin to work is if the printer profile was severely malformed as there is no way the colorimetric tables could fit sRGB. Correction. It's possible to double profile a printer such that the profile the printer uses is restricted to sRGB. For instance make a normal printer profile then create a second profile but print the target in sRGB using the first profile to manage coior (instead of color management off). This profile could then be assigned to the image. It would, of course, limit colors to those printable in sRGB. But doing something like that is weird, to say the least.
« Last Edit: March 22, 2018, 07:02:23 PM by Doug Gray »
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Rand47

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Re: Unexpected result after converting image profile to softproof profile
« Reply #17 on: March 22, 2018, 07:08:19 PM »

All . . .

I'm really glad I was moxie enough to expose my ignorance on this more fully.  This discussion has been VERY helpful.  Doug, thanks for the explication of the Costco situation, Dry Creek's instructions in this regard are far from clear to me.  Probably because I was reading my ignorance into the situation. 

As I said, I do all my own printing on my SC P600 and SC P5000 printers.  When I need to go BIG for someone, I have access to, and the ICC profiles for the papers I use for, an SC P20000 printer.  I soft proof here as normal and take the soft proofed files to the location where we print them in the same way I do here in my own digital darkroom. 

But this subject has been one of great confusion for folk I've been trying to help in our local camera club who only use labs of one sort or another.  I've been educated enough (thanks to Andrew) to steer them away from the "one size fits all labs"  (e.g. one who will remain nameless that has a single ICC profile for all their papers/printers!  LOL), but I've not been savvy enough to be able to provide really good direction for Costco (especially) and some other labs that have multiple, paper-specific profiles, and instruct to soft proof "to" but not convert the file on export. 

So again, thank you for this discussion and any ongoing insight that may/will be provided.  If you genuine experts have to nuance your responses to get me to "get it" - then I don't feel so bad about not getting it on my own!   ::)

Best regards,
Rand
« Last Edit: March 22, 2018, 07:27:59 PM by Rand47 »
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Mark D Segal

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Re: Unexpected result after converting image profile to softproof profile
« Reply #18 on: March 23, 2018, 12:07:31 PM »

Having referenced some guidance material on preparing images for an external processing lab, I think some clarification of the details of what to provide them may be helpful here. If you have the lab’s profile and if you know which RGB colour space they want the photos to be in, you set-up a proof condition in Lr or Ps to soft proof your photos with their printer/paper profile. If the lab ONLY specifies the working colour space in which they expect the photos (e.g. sRGB, ARGB(98)) you should convert the photo to that working space. If the lab specifies that the image should be in a colour working space such as sRGB or ARGB(98) AND still provides a paper/printer profile for soft proofing, then you should work in the requested colour space and in the soft-proof condition dialog you should select both the printing service’s profile and “Preserve RGB Numbers” option, which for soft-proofing purposes will simulate what the print would look like if these RGB numbers were sent to this printer/paper combination. If the lab allows you to send the photo for printing readied with their printer profile, you should convert the image to that profile using the Convert to Profile procedure in Photoshop, but tell them you’ve done that so they won’t make any further adjustments. This is supposed to be the surest way of getting back what you expected. (ref. Tom Ashe, "Color Management and Quality Output", Chapter 16).

Having done this, I would observe the photo is now purposed to that one output condition.
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Re: Unexpected result after converting image profile to softproof profile
« Reply #19 on: March 23, 2018, 12:32:32 PM »

Having referenced some guidance material on preparing images for an external processing lab, I think some clarification of the details of what to provide them may be helpful here. If you have the lab’s profile and if you know which RGB colour space they want the photos to be in, you set-up a proof condition in Lr or Ps to soft proof your photos with their printer/paper profile. If the lab ONLY specifies the working colour space in which they expect the photos (e.g. sRGB, ARGB(98)) you should convert the photo to that working space. If the lab specifies that the image should be in a colour working space such as sRGB or ARGB(98) AND still provides a paper/printer profile for soft proofing, then you should work in the requested colour space and in the soft-proof condition dialog you should select both the printing service’s profile and “Preserve RGB Numbers” option, which for soft-proofing purposes will simulate what the print would look like if these RGB numbers were sent to this printer/paper combination. If the lab allows you to send the photo for printing readied with their printer profile, you should convert the image to that profile using the Convert to Profile procedure in Photoshop, but tell them you’ve done that so they won’t make any further adjustments. This is supposed to be the surest way of getting back what you expected. (ref. Tom Ashe, "Color Management and Quality Output", Chapter 16).

Having done this, I would observe the photo is now purposed to that one output condition.

Mark, could you talk a little bit more about "Preserve RGB Numbers" is used for and what it actually does?  It looks to me like it shows a preview of the transformation without a rendering intent.  Are you saying that a commercial printing service would print without applying a rendering intent, and that we should re-adjust the image with a curve to apply a rendering intent by eye?  I'm not trying to make an argument here, just trying to learn about this :)
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