Color profiles and Color Settings in Illustrator

[Custom_Grafx]

Have been reading alot about color profiling and setup in versaworks re ink limits and the such since about last november - and finally getting my head around it all.

The internet helped alot with the above, and I have been reading like mad about everything, and have enjoyed learning so many new and useful things.

I'm now trying to find information about what settings to use in AI so that I see what I'm going to get out of versaworks as closely as possible.

I have an x-rite i1, and I have used it to both create a monitor profile for my monitor, and to also linearize my roland printer, and to create custom profiles for different types of media as well.

The question I'm asking I guess, is what do you put your color settings on in AI? Do you go to view and change your proof options to your custom monitor profile? When you print from AI to VW, do you go to the color managment section in the print dialog and change the profile to your custom ICC that you created with your i1?

Why can't I find straightforward info and steps on this very simple request anywhere on the net?

Many thanks in advance,
John

 

[eye4clr]

First, sort out the simple workflow....Only convert your file from it's native RGB or CMYK working space to the printer's output profile ONCE! This seems obvious but is a common mistake when you're first getting started. Another way to present this is do not convert to the output profile in Ill. AND in your RIP. Be absolutely certain it is only getting applied in one or the other. For simplicity, 99% of people apply in the RIP and keep the design and layout apps passive players in the color conversion process.

Second, make sure your working space profiles agree in your desktop apps and you RIP. So if you use sRGB and US Web Coated SWOP in adobe apps, be sure your RIP has it's input profiles set the exact same way.

Be sure your monitor profile is actually being used by your OS. Adobe apps will recognize this automatically. Your RIP may need to be configured as to what monitor profile to use.

Do not use your monitor as the proofing profile. The monitor is not the thing you're trying to proof for, the print is. The monitor profile's only role is to display what is in your file accurately. It is not a working space profile, nor is it your final output for printing. You may set the proofing profile in the adobe apps to be your printer profile. This will give a more accurate presentation (using the monitor profile) on your monitor as to how it will print. Note that this does not actually convert the file. It is simply an on the fly simulation on screen.

We can go on and on about soft proofing on the monitor and the whole WYSIWYG thing. Personally, I find that if your profiles are well made and functioning properly, and your workflow is in place properly, you don't usually need to fuss with a softproof. The output will naturally be close to the on screen display.

If you really want to get serious about your soft proof, expect to invest in proper lighting and or a light box, and be sure you have a high quality monitor that allows you to adjust the individual R, G, and B settings individually to fine tune the white balance (AKA color temperature expressed in degrees kelvin). For the huge majority of users, it simply isn't worth the hassle and expense of getting really serious about the soft proof.

Hope this helps.

 

[Custom_Grafx]

Hi there, and many thanks for the time you took to reply.

I read through everything a few times, and there's still a couple of things I don't get.

I have a few questions;

Keep the design app "passive".
How do you do this? In AI, in edit/color settings, do you do this by turning rgb and cmyk color managment settings to "off"? What about when you 'print' to your RIP from AI, what do you have as your settings in the 'color management' section? Color handling, printer profile and rendering intent. I usually have it as, "let illustrator determine colors", change printer profile to my custom ICC that I have made for my media, and rendering intent as "relative colorimetric" usually, and for photos, "perceptual".

The thing I find confusing is that AI doubles up what the RIP has in there? Like the intents for example. Also, should I be using US SWOP in the AI printer dialog because in VW it's US SWOP?

 

[toli13]

The media profiles you have created are the output profiles for Versaworks. In the print dialogue of AI you should set "Printer defines Colours" (or similar, mine is in German). As eye4clr said, this is the way to let the RIP do the colour conversion. AI hands out the data to the RIP in the colour space you have set in general AI settings. So, for example, you have set Adobe RGB(1998) as your RGB colour space, no transformations to CMYK will be done by AI if you do not set "Illustrator defines colours".
Tilo

 

[eye4clr]

Tilo is spot on.

Let's talk output only right now from Ill -> RIP. Do as Tilo says exactly. Otherwise, what may be going on is Ill converts to from your working space to the printer profile you built, then the rip does the exact same conversion again. This will likely produce some spectacularly bad results. You only want one conversion from working space to output profile (you built). Generally it is cleanest and easiest to just have the RIP do this. This is what I mean by having your workstation apps be "passive". It is not generally their job to convert from working space to output profile.

The settings within the adobe products color policies (not the ones in the print dialog) are how incoming files are handled. Normally you want to be made aware of files that are coming in with embedded profiles that differ from your working space. Just yesterday I had some images come in with some random "linear rgb" profile. I have no clue what that is, so it is my responsibility to reproduce what is in the file. So I converted to my RGB working space when brining it into Photoshop. This brought the odd-ball images in line with my day to day workflow while removing the possibility that the RIP will think the image is something it is not as my RIP's input profiles are in agreement with my adobe apps. Had photoshop been set to "use embedded profile" without giving me the dialog on open, I would have skipped merrily along and sent the wrong color format to my RIP.

Set your design apps to "Preserve Embedded Profiles" but have all the check boxes CHECKED for Profile Mismatches, Missing Profiles, and Ask When Pasting. Then you'll be made aware of files coming in that don't match your in house setup. When confronted with a profile mismatch dialog, convert to from the embedded profile to your working space. When given a Missing Profile message, assume the file is sRGB or US Web Coated SWOP and either have these as your day to day working spaces or assign them to this incoming file then convert to you working space if it differs from these common profiles.

The dogmatic rules for rendering intents has been Perceptual for images, and Relative Colorimetric for vector and spot. This is fine in theory, but in practice there are so many files that are partially rasterized to resolve transparencies and effects that you may have a mix of raster/vector where you don't expect it. For safety sake, it is usually easiest to just go with Perceptual for everything for basic printing needs. Also it seems that Onyx has some pretty nasty relative colorimetric rendering so I stay away from it.

 

[Custom_Grafx]

Many thanks guys - I appreciate the info and help. It's starting to make more sense to me now.

One last question (for now), in the print dialog box, there is a box "preserve CMYK numbers", should I check this or uncheck it? Why would I want or not want to preserve CMYK numbers? Again, is this something that the RIP should decide and if so, should I uncheck this?

Oh, another question just came to mind... In VersaWorks RIP, there is a checkbox for whether or not you want to use the embedded ICC profile. Is there a best practice for this option? Should it always be checked?

Thanks in advance,
John

 

[toli13]

Hi John,
if you keep this "preserve CMYK numbers" activated, what I suggest, the values you set in Illustrator for your vector designs won't be affected by perceptual rendering intent. So, if you set a pure green for some object it will be sent as 100% Y + 100% C to your RIP. Otherwise your green will be included in the transformations caused by the perceptual rendering intent. Perceptual means, that the relations between the colours visibly don't change, but all colours are changed a little to get all colours inside the gamut. All colours will be "squeezed" the same amount, even those which are already inside the gamut. So the relations between the colours keep about the same, but your green will be finally something like 98% Y + 97 % C + 3% K or so. Hope, I've explained that correct, as I'm no colour scientist. Maybe eye4clr can check this, as he's obviously more an expert than me.
In VersaWorks you should have the checkbox activated. This means for example, if you have set Adobe RGB (1998) as your RGB workspace and you get an sRGB image with included profile from somebody to print, your RIP will choose sRGB as source for the colour transformations instead of the preset. Otherwise VersaWorks assumes, that it's an image with Adobe RGB (1998) and prints nicely red skin tones. Nevertheless you always should be careful with customer files you don't know which colour space they are made in. Always ask for that. It's a huge difference between sRGB and Adobe RGB (1998).
Hope, this helps
Tilo

 

[eye4clr]

preserve = YES

It is in line with what's been said so far. Leave the final conversion step to your RIP and use the design/adobe apps to funnel incoming files into your in-house workflow.

 

[Custom_Grafx]

Many thanks to both of you for all this help. I am printing this out and keeping for reference. Amazing how hard it is to find this info in the one place on the net. Maybe there needs to be a site dedicated to color management for the sign industry. I know this forum has a section like that though... hopefully this thread will be of use in future searches

 

[signswi]

Keep in mind you want to stay working in .ai as .eps doesn't properly support ICC and can sometimes cause problems. Also there are many, many color forums but most are targeted for offset, and those that cover large format tend not to be great. It also gets confusing with the different standards on the two sides of the pond. A number of photography forums also cover large format color management as so many photographers print their own now. I like a GRACoL workflow myself, just throwing that out there--even though it's offset targeted like SWOP the gamut is much larger and nicer for large format. Not as good as rolling your own but that's another thread...

 

[Rooster]

Keep in mind you want to stay working in .ai as .eps doesn't properly support ICC and can sometimes cause problems.

.pdf is the new .eps with full icc support.

If your rip has a black point compensation feature, then you can let the rip handle the color conversion. Without that feature the 3/4 tones will appear very dark compared to your monitor. If your rip doesn't have it, then you can convert the files to the output profile in either photoshop or during the pdf process and apply it then.