How to get what the client is seeing on her monitor to print

[TᴀW]

Hello again!

I'm still working on these childrens books, and here's where I'm at.

I calibrated and profiled my monitor and the client's monitor.

The client has been merrily filling in the black outlines of her drawings in Photoshop. She picks the CMYK swatch that looks good on her monitor and fills in the drawing.

Now, I have on my computer a copy of her monitor profile. When I open her PSD images (which are in CMYK mode, with a generic coated SWOP profile), it seems to me that I should:

(a) discard the attached profile, preserving the CMYK numbers

(b) convert the image to the RGB profile of her monitor

(c) convert the image to the CMYK profile of the printing press (or perhaps back to a generic CMYK profile, since we don't yet know where we're printing).

Is this correct?

Or perhaps, when I open her PSD images, I should

(a) use the embedded profile (US Web coated SWOP)

(b) convert to the destination profile of the printing press

Any guidance appreciated,

Ariel

[Lou Dina]

Ariel,

If you want control over your color, you are going to have to learn the basics.  Sorry, but there is no good way around it and it takes some study. I will try to give you a little guidance for now, but you need to read a good color management book, like Real World Color Management to get your arms around the concepts.

1.  First, I will assume BOTH you and your client have properly calibrated monitors and that they are calibrated to the exact same parameters.  If not, game over.  You will never see on your monitor what she sees on hers unless this is true.

2.  Your client needs to specify a CMYK working space to give the CMYK numbers color meaning.  If she does not do this, then find out what her "default CMYK" is set to in Photoshop.  If she has not picked a CMYK space, Photoshop will assume what is set under "Color Settings".  Ideally, she would save her files with the CMYK profile embedded in the file.  This makes it clear what she is using.

3.  Once you know what flavor of CMYK she is using, then you should "Assign" that same exact CMYK profile to it when opening.  If the file has the CMYK profile embedded when saved, you will know exactly what she is using, even if she doesn't know. Now, if all of the above have been done, you should see on your monitor what she saw on hers.

4.  Until you know where you will be sending the file for output, leave the profile set to what she used.  You should ask your printer for their specifications for file preparation....ie, color profile, resolution, ink limits, etc.  After you have found out from your printer what they want, then you can address conversion, if required.  They may want you to supply US Web Coated SWOP v2 files, and if that is the space you are using, then you should be done.  Of course, you need to check resolution, verify that ink limits are below their maximum, etc.

Sadly, not all printers know what they are doing.  Some are clueless about color management, profiles, dot gain, ink limits, etc.

Get the book or study the subject on internet sites.  If you don't understand the principles, you will continue to struggle and your jobs may not turn out well.  One other thing....insist that the printer provide  a color "contract" proof of the job BEFORE it goes to press.  If it looks terrible, something is wrong and you can catch it early and figure out what needs to be changed.  If it looks great, then it is the printer's obligation to match the proof on press, within reasonable tolerances.  Once you sign off on the contract proof, it should be set in stone (for both of you).

Lou

[TᴀW]

Lou,

Thanks for responding.

First off, I have borrowed and read a copy of Real World Color Management 2nd edition. It's still on my shelf, and I'm trying to figure it out. But this stuff is confusing (and I have two degrees from a top British university -- but not in color management).

1. The parameters of our monitors are close, but not identical. I couldn't get her cheaper monitor dark enough. But anyway, our viewing environments are

pretty different. So I suppose I should just ignore what I'm seeing on my monitor (I'm not doing colour adjustments, just the layout etc.).

2. Her files are being saved with the default US web coated SWOP.

3. Okay, this is making sense. I think I went on a wild goose chase by asking her for her monitor profile. After all, when she chooses a CMYK number + a CMYK press profile (the default), we now have an "objective" colour defined (I guess that means a specific Lab colour?) And because her monitor is profiled, Photoshop knows what to do to get her monitor to produce that same Lab colour. And when I open that image on my computer, since my monitor is also profiled, Photoshop should know what to do to get it to produce that same Lab colour. So, if what I'm saying here is correct, the only thing I don't understand is why you said I won't be seeing the same colour on my monitor as she is on hers. And the only answer I can think of (please correct me if I'm wrong), is that our viewing environments are different.

So to summarize: I should simply let Photoshop "use the embedded profile".

Let me know if I'm not understanding this properly.

Thanks,

Ariel

[Lou Dina]

Ariel,

Yes...it is confusing at first.  If you will be doing a lot of this, it is worth understanding.  If this book is a one time shot, then maybe not.

I said IF your monitors are both accurately calibrated  to the same parameters, you should see the same thing.  But, if hers is calibrated to very different parameters than yours, you will see a different interpretation of the numbers on your screen than she does on hers.  Yes, ambient lighting environment can have some impact, so it would be best if you both worked in a moderate to dimly lit environment. 

Photoshop, being a color managed application, will see the monitor profile in the loop automatically and will instantaneously adjust colors as they are being sent to your monitor (and hers).  So, all you need is an accurate monitor profile, and Photoshop will get the colors right.  And yes, Lab is operating silently in the background as the universal translator.  Your CMYK numbers, PLUS a correct color profile, are enough to identify the exact hue, saturation and brightness of a given color.  Even though you may have a CMYK file on your screen, Photoshop is silently keeping track of everything in the background in Lab terms.  Lab is the only color space on your system that is "device independent" and unambiguous.  It doesn't need a profile, since it IS the standard.  A given set of Lab coordinates always means a specific color, regardless of the monitor, printer or press used for final output.  But that is not true of CMYK or RGB...they need a profile in addition to the numbers.

So, I think you have it now.  Yes, let Photoshop use the embedded profile IF one is embedded.  If one is not embedded, you need to find out what your client used, or what the default setting is in their Photoshop program, so you can ASSIGN the same profile to the file.  You want your CMYK numbers AND your CMYK color space to match hers.  Clear?

Lou

[TᴀW]

Lou,

If you will be doing a lot of this, it is worth understanding.  If this book is a one time shot, then maybe not.

Well, till now I've been doing mainly book interiors without colour. But I feel I should know about colour management, because it keeps coming up. Anyway, no harm in exercising those flabby grey cells!

I think I'm getting it slowly. I've understood what you've just said, except for one thing:

But, if hers is calibrated to very different parameters than yours, you will see a different interpretation of the numbers on your screen than she does on hers.

CMYK numbers + a CMYK press profile = Lab colour.

RGB numbers + my monitor's RGB profile = Lab colour.

RGB numbers + her monitor's RGB profile = Lab colour.

Where does monitor calibration come into this? I understand that monitor calibration and monitor profiling are two separate issues. If we've all got our profiles sorted out, why should the monitor calibration make a difference here? Ambient lighting I understand will make a difference, but if you could "throw some light" on how calibration fits into this equation, that would be great.

[Printer_Rick]

Arïel wrote:

CMYK numbers + a CMYK press profile = Lab colour.

RGB numbers + my monitor's RGB profile = Lab colour.

RGB numbers + her monitor's RGB profile = Lab colour.

Where does monitor calibration come into this? I understand that monitor calibration and monitor profiling are two separate issues. If we've all got our profiles sorted out, why should the monitor calibration make a difference here? Ambient lighting I understand will make a difference, but if you could "throw some light" on how calibration fits into this equation, that would be great.

CMYK numbers + a CMYK press profile = Lab color

I would say this is true, and the Lab values are re-interpreted back into RGB for display. You don't see this happening. But the monitor being an RGB device, this has to occur.

There are also separation parameters built into a CMYK profile, but that is more of a concern for images. I believe you are dealing with illustrations. I forgot to ask something earlier - were these illustrations created from scratch in CMYK? If so, please disregard what I said earlier about source RGB, it does not apply.

RGB numbers + monitor profile = Lab color

No, this isn't quite true, unless it's an RGB image tagged with a monitor profile (not a good idea). RGB files typically have device independent display profiles. Most of the time this is either sRGB or aRGB. These translate to Lab values, which are then rendered into your monitor's RGB color space.

You may ask why everyone doesn't use monitor profiles, to avoid this. The reason is simple. It's a device profile, and the image being repurposed (for print or web) has no relation to a specific monitor. sRGB describes an average PC monitor, but not a specific monitor. aRGB was designed as a good source space for print design.

These two spaces (sRGB, aRGB) are fixed, and used the world over. Monitor profiles vary greatly, there is a lack of consistency. That's why they don't make good source profiles for file conversions.

The monitor calibration and profile go hand in hand. A new profile is generated when you calibrate, or the old one gets overwritten.

[Printer_Rick]

Arïel wrote:

RGB numbers + my monitor's RGB profile = Lab colour.

RGB numbers + her monitor's RGB profile = Lab colour.

I've done some thinking on this, maybe this will help:

A monitor is an individual's proofing tool. You have mentioned using monitor profiles as document color spaces, and I've stated that's a bad idea but I don't know if I've explained properly.

People should use a universal color space (such as aRGB) as a document RGB color space. If you use a monitor profile as an RGB document color space, you're defining the file source color based on your individual proofing tool. This is not ideal, because a proof is a destination, not a source. Monitors can't be universal. They are all different. Some are better than others (as you stated, yours is better than your client's). And monitors don't get passed around with files.

A monitor is not very different from a calibrated desk top printer, in a proofing sense. The actual printout has no relation to to the file, it is a representation of the file. Just like what you see on the monitor has no relation to the file, it's an interpretation of the file color. The advantage with the printout (recorded color information) is you can distribute it as a real physical reference, no need to send the print device.

It is true that if a file has someone else's monitor profile embedded, Photoshop can still render the color accurately on your monitor. But with RGB images, users deal primarily with image capture. Most of the time the capture device is a digital camera. The camera embeds a source profile. It never embeds a monitor profile, because the monitor has no relation to the capture. If you convert the file to a monitor color space, it is a totally unnecessary conversion and you may end up clipping colors in the process (the monitors color gamut can be limiting).

Good color management is all about two things:

1. Preserving the source color.

2. Proofing the source color to match the final destination. This can be a soft proof or a contract proof printout. With good color management, the proof color is an accurate rendition of the final destination, in your case the press result.

By the way don't feel bad about being confused by all of this color management stuff. I don't fully understand it either. I'm not sure anyone does. Looking through all the Adobe forums, many of the questions and problems can be traced back to a breakdown in color management.

Let me know if any of this doesn't make sense. I will post about CMYK - CMYK conversion from InDesign sometime soon.

[TᴀW]

Hi Rick,

Most of the time the capture device is a digital camera

Right, but in this case not, because she's picking colours based on what she sees in the swatches palette on her monitor. The way it looks to me, this situation can be regarded in two ways:

1. She's choosing colours from swatches (let's say RGB swatches). So she's got RGB numbers + her monitor profile = a Lab colour. So to reproduce that on my monitor I should use her RGB numbers tagged with her monitor profile...

2. or, You could say: she's choosing swatches + a press profile = Lab colour. Her monitor is profiled, so Photoshop knows how to get her to see that Lab colour on her monitor. And for me to see those colours, I need her swatches embedded with the press profile she's using, and because I've got a profiled monitor, Photoshop will again produce the right Lab colour on my monitor.

I think that (2) is more normal? And anyway, in fact she's choosing from a bunch of CMYK swatches.

[Printer_Rick]

Arïel wrote:

Hi Rick,

Right, but in this case not, because she's picking colours based on what she sees in the swatches palette on her monitor. The way it looks to me, this situation can be regarded in two ways:

1. She's choosing colours from swatches (let's say RGB swatches). So she's got RGB numbers + her monitor profile = a Lab colour. So to reproduce that on my monitor I should use her RGB numbers tagged with her monitor profile...

2. or, You could say: she's choosing swatches + a press profile = Lab colour. Her monitor is profiled, so Photoshop knows how to get her to see that Lab colour on her monitor. And for me to see those colours, I need her swatches embedded with the press profile she's using, and because I've got a profiled monitor, Photoshop will again produce the right Lab colour on my monitor.

I think that (2) is more normal? And anyway, in fact she's choosing from a bunch of CMYK swatches.

2 is much more normal. The only time you'd have the 1 scenario is if the RGB image has her monitor profile embedded.

You can in fact see profiled RGB on two different calibrated monitors, and see consistent color (if that's what you're asking). On both monitors the document RGB (i.e. aRGB) is translated into Lab, then back to the monitor RGB. This happens behind the curtains.

But with this job, you are dealing with CMYK images so a document RGB color space is a non-issue.

[TᴀW]

Thanks Rick, I think I'm beginning to get a handle on this!

[Printer_Rick]

Arïel wrote:

(a) discard the attached profile, preserving the CMYK numbers

(b) convert the image to the RGB profile of her monitor

(c) convert the image to the CMYK profile of the printing press (or perhaps back to a generic CMYK profile, since we don't yet know where we're printing).

Is this correct?

Or perhaps, when I open her PSD images, I should

(a) use the embedded profile (US Web coated SWOP)

(b) convert to the destination profile of the printing press

Any guidance appreciated,

Ariel

Your 2nd choice is better, much better.

Best case scenario would have been only one conversion, RGB - CMYK. But since it's already been converted to CMYK, it is best to do a 2nd conversion, to the profile that describes the true printing condition (the press profile you mention)

[Printer_Rick]

Lou beat me to it, his advice was very good.

It may very well be that leaving them US Web Coated SWOP v2 is the best route. When you mentioned a press profile, I assumed that the printer had supplied you with one. If that is the case then a CMYK - CMYK conversion is in order, as I mentioned before. DO NOT go back to RGB.

Whatever you do don't follow that first sequence. You mention discarding the attached profile, that's not a good plan. And don't use her monitor profile, that has no meaning on your machine.

You also mentioned:

The client has been merrily filling in the black outlines of her drawings in Photoshop. She picks the CMYK swatch that looks good on her monitor and fills in the drawing.

Please elaborate on "CMYK swatch" Are you referring to a physical swatch book, or swatches in Photoshop?

[TᴀW]

Rick,

Thanks for you response.

I loaded up the Focoltone library into her swatch palette, and she's picking colours from there and using them in her artwork, based on the way they appear on her screen.

Since her monitor is calibrated and profiled, this should be fairly accurate?

[Printer_Rick]

This depends on 3 things I think:

1. Her monitor is accurate and room viewing conditions are ideal.

2. She is in CMYK mode, or in RGB with Proof View enabled, so she sees a CMYK rendering

3. US Web Coated SWOP v2 closely describes the print condition you will use

There is great, great debate on CMYK - CMYK conversions, which I mentioned earlier. Technically when following good color management practices to the T, all color information should be converted to the press profile that accurately describes the final print condition (press, paper, ink, screening, etc)

But to be honest there aren't many people who do that. I am a printer, and most of what I get is CMYK. Probably 90% is US Web Coated SWOP v2. This is the "Generic CMYK". Please understand there is really no such thing as a generic CMYK, I call it that because it is the Adobe default and it's what almost everyone uses. Yes, extremely color conscious designers do not do use this default. But most designers and print buyers I know are more concerned with turnaround time than with color (sadly enough).

My dilemma as a printer is, do I convert this CMYK, or no? The answer is a resounding no, unless the customer specifically requests it. The reason I cannot, must not convert, is because if a color issue arises, it's on me. I have taken ownership because I changed the file. Not only that, but it is an extra step in the prepress process. It is treating CMYK just as you would RGB. RGB is a red flag in the print industry, if you start treating everything like RGB then everything is a red flag, which is completely counterproductive.

The print industry standard is to preserve incoming CMYK numbers in all circumstances, unless there is specific, special instruction not to do this, or if there is a concern with Total Ink Limit. This arises depending on the paper being used – uncoated paper cannot receive as much ink as coated paper. So if that is a concern then yes, I have to convert the customer CMYK to my uncoated CMYK, otherwise the whole job prints wrong and we have to reprint.

I am very glad to see you are concerned with color. As I stated most of the time these days it's all about how fast the job can get out the door. Any focus on quality is preferable to rushing jobs through. These days I don't deal with a lot of color issues, and to tell the truth I kind of miss that.

Technically, when you perform a color conversion, there is a loss of quality in the pixels of the image. This may not make sense, but it is true. This is another reason that as a printer I can't go converting CMYK - CMYK. Many times the damage is not at all noticeable, so the concern for accurate color may outweigh the slight hit to the gray levels in the channels. I must stress – do not take the files back to RGB, then to CMYK again. One conversion of a file is always the best workflow. That's why I mentioned earlier than it would have been best if you had received the source RGB from your client.

But don't worry about that too much, from another perspective it is good that she converted to CMYK. The reason I say that is, if she had been working in RGB, the chances of her always remembering to turn on Proof View every time she opened an image are slim to none. This is a major flaw in the Photoshop application, the fact that you cannot save a file with Proof View enabled.

Bottom line, if US Web Coated SWOP v2 is not your exact printing condition, then you may want to convert to the proper press profile for the most accurate color result. Please check with the printer, thoroughly describe your situation. They may say "just leave it US Web Coated SWOP v2". Or they may say "yes, definitely convert to our press profile".

If you do perform a CMYK - CMYK conversion, remember the principle behind this course of action. Yes, your client did not see the final conversion, or the final destination CMYK on her monitor. However, the idea behind the final conversion is to preserve appearance, in the true print condition.

When you convert to to the final CMYK, you should not see a huge color shift, the color should be mostly preserved. That is color management, working just as it is supposed to. If for some reason you see a drastic color change when you convert, let us know we will try to figure out the problem.

I apologize for rambling on and on, I get carried away sometimes.

[TᴀW]

Rick,

Thank you for taking the time to contribute your experience here. It's becoming clear to me that the best course of action is to allow all the CS applications to preserve the embedded profile (the default SWOP), and eventually convert to the press profile if they have one.

Since after going through Photoshop and Illustrator (I'm having to use both), the book will actually be laid out in Indesign, it seems that the best approach is to convert to the press profile at the time I export from InDesign to PDF?

[Printer_Rick]

Arïel wrote:

Rick,

Thank you for taking the time to contribute your experience here. It's becoming clear to me that the best course of action is to allow all the CS applications to preserve the embedded profile (the default SWOP), and eventually convert to the press profile if they have one.

Since after going through Photoshop and Illustrator (I'm having to use both), the book will actually be laid out in Indesign, it seems that the best approach is to convert to the press profile at the time I export from InDesign to PDF?

You can do that but it is very tricky. ID defaults to preserve CMYK numbers.

It can work if the ID CMYK profile is the same as the images. Then when you export you convert to the press profile.

If you are using all three apps with common colors, you need to make sure these colors remain consistent. You don't want the Photoshop red, InDesign red, and Illustrator red being 3 different things.

I will think about this some more and get back with you. CMYK - CMYK can be difficult. Perhaps that's another reason it's not a print industry standard!

[Printer_Rick]

Arïel wrote:

Since after going through Photoshop and Illustrator (I'm having to use both), the book will actually be laid out in Indesign, it seems that the best approach is to convert to the press profile at the time I export from InDesign to PDF?

Before you perform any special CMYK - CMYK conversion, please do the following:

1. Open an image with all your swatches. The image currently has US Web Coated SWOP v2 embedded.

2. Go to Proof Setup: Custom.

3. Select the press profile.

4. Click "Preserve numbers". Don't click the options at the bottom. Hit enter

5. Hit "Command Y" over and over. Do you see a big color shift? Let me know then we will proceed further.

[TᴀW]

Rick, thank you. I'm away for the weekend and will look at what you've written more carefully at the beginning of next week.

Thanks to all and have a nice weekend.

Ariel

[TᴀW]

5. Hit "Command Y" over and over. Do you see a big color shift? Let me know then we will proceed further.

Well, I don't have the final press profile yet, so I just chose a Japanese coated one at random.

And yes, there is a biggish colour shift, specifically, the colours get darker. Without "Preserve CMYK numbers" there still is a shift, but much less (which makes sense, I guess, because the whole point is that the profile adjusts the CMYK numbers so as to preserve the Lab value as much as possible with the new press profile.)

[Printer_Rick]

Arïel wrote:

5. Hit "Command Y" over and over. Do you see a big color shift? Let me know then we will proceed further.

Well, I don't have the final press profile yet, so I just chose a Japanese coated one at random.

And yes, there is a biggish colour shift, specifically, the colours get darker. Without "Preserve CMYK numbers" there still is a shift, but much less (which makes sense, I guess, because the whole point is that the profile adjusts the CMYK numbers so as to preserve the Lab value as much as possible with the new press profile.)

You understand this well. If when you get the profile, if you do not see a big shift with preserve numbers, you may be able to leave the images in their current color space.

If you do a CMYK - CMYK conversion, I will explain in more detail. This conversion involves using Acrobat Pro (hope you have this application)

[TᴀW]

"This conversion involves using Acrobat Pro (hope you have this

application)"

Yes I do. I can see what's coming: Tools>Print Production>Convert Colors (am

I right? )

That's a dreaded little dialog box right there. In fact, I've tried on

several occassions to use it to convert a colour pdf to greyscale, and it

always fouls up when it hits richs black (registration black). It will not

get rid of the numbers on the CMY plates. If you know how to fix that

problem, I'd love to hear!

[Printer_Rick]

Arïel wrote:

"This conversion involves using Acrobat Pro (hope you have this

application)"

Yes I do. I can see what's coming: Tools>Print Production>Convert Colors (am

I right? )

That's a dreaded little dialog box right there. In fact, I've tried on

several occassions to use it to convert a colour pdf to greyscale, and it

always fouls up when it hits richs black (registration black). It will not

get rid of the numbers on the CMY plates. If you know how to fix that

problem, I'd love to hear!

Convert colors to Output Intent, and select your working gray profile

This converts everything to grayscale. If there is Device Gray, the number values won't change, but it will become calibrated.

And you are right, this tool is the best way to do CMYK - CMYK, you can enable "Preserve Black".

For example if everything was US Web Coated SWOP (ID, AI, PS), you would output from InDesign using PDF/X-4 with "Convert to Destination" Document CMYK

It is best to convert the colors in the PDF (I think) because there everything is composited into an output file. If all support files were set up properly, you will know that everything in the PDF is US Web Coated SWOP. You can convert to a new Output Intent using Acrobat. Then thoroughly check the entire PDF. The AI blue, the ID blue, the PS blue - they all need to be the same blue, right? Use Output Preview in Acrobat Pro to measure the values, you will know if all your colors are consistent.

[TᴀW]

"If there is Device Gray, the number values won't change, but it will become

calibrated."

Are you saying that rich black (100,100,100,100) is considered a device

grey? I still don't understand why Acrobat doesn't change 100,100,100,100

to 0,0,0,100 even when I choose a gray profile? I suppose it doesn't make a

difference for the press, because they're only printing the black plate. But

it causes a problem in that doing a preflight check for "Outputs more than

One Plate" throws an error?

[Printer_Rick]

Arïel wrote:

Are you saying that rich black (100,100,100,100) is considered a device

grey? I still don't understand why Acrobat doesn't change 100,100,100,100

to 0,0,0,100 even when I choose a gray profile? I suppose it doesn't make a

difference for the press, because they're only printing the black plate. But

it causes a problem in that doing a preflight check for "Outputs more than

One Plate" throws an error?

No, you need to convert to a gray output intent. Then you won't have any CMY, nothing but black ink. In Output Preview you will only see Black.

Try Dot Gain 20 as an Output Intent, you shouldn't see any registration color.

On another note, try to avoid outputting registration marks (unless your printer is asking for them for some reason). They just cause problems. As long as you include bleed area, the trim box within tells the page size, that's all a printer should need.

[TᴀW]

Rick, this is incredibly useful. Dot gain does indeed pass the Preflight

test! (with preserve black and embed output intent selected). I've always

used Gray Gamma 2.2.

Can you explain, though, why using Gray Gamma doesn't get rid of

registration black, whereas Dot gain does?