....these keep printing with a red / purple / blue / green gradient, despite various attempts to reconfigure my color management settings (both with "none" and "convert to cmyk"). Most of these files are .ai files placed into InDesign....obviously they appear correctly on my screen on the original file and the exported pdf. Additionally, the files print correctly to color laserjet printers at school, so I am beginning to think it may be an issue with Lulu.
Does anyone know if it is something I am doing wrong, or if it is a common issue with Lulu printing?
Thank you very much for the help!
"..keep printing with a red / purple..."
Are you saying you've received the product from Lulu?
Yes...I have printed several tests, experimenting with different color management settings that could be causing issues...and each copy has similar color gradient issues.
CAD drawings have gray lines representing hatches or distant building lines
Most likely, the color build of these hatches are a percentage of CMY with little or no black. If this is the case, the color build should just be a percentage of black.
I think you are right! Thanks for the help!
In illustrator in the "color" dialog box, the fader shows 50% grayscale. When I switched to the CMYK fader, it shows only about 2% black.
I must admit that I am quite ignorant about this topic.....Is there a way to change this color build without going through all of the layers and changing each to a different grayscale color? These were colors automatically assigned from my original CAD file...I guess I just don't understand this concept of a color build.
Again, thank you for the help!
It sounds like they are starting out as 50% black (grayscale) and are being converted to CMYK. This would happen if there is a profile conversion going on during export and you don't have preserve numbers selected, or a conversion happening during the place operation and your policy is to convert to the current workspace and preserve appearance rather than numbers when there is a profile mismatch.
What do you see for numbers in the Separations Preview in ID, and the Output Preview in Acrobat Pro (if you have it) before sending to LuLu? Move the curso over one of these lines to read the numbers.
Most of the lines have these or similar numbers in both previews in InDesign and Acrobat:
I exported with the following settings for output:
Conversion: Convert to Destination (Preserve Numbers)
Destination: US Web Coated (SWOP) v2
Profile Inclusion Policy: Don't include profiles
Also, my file has the following color settings:
RGB: Preserve Embedded Profiles
CMYK: Preserve Numbers
However, this last "Preserve Numbers" I may have changed after already placing my files....if this is the case, can I just re-place my files with this setting and have the appropriate grayscale colors?
Thanks a lot!
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Well, it appears the problem is in the import, not the export. Try replacing one file and see if the numbers work. If not, you should probably resave all the files WITHOUT embedded profiles and place those, instead. With no emebedded profiles, ID will automatically presume they are in the current working space and preserve the numbers for CMYK.
Are you sure, though that the color mode on these drawings is CMYK? If it's RGB, then that would explain why you get CMYK grays and black -- you are converting all RGB to Swop on export.
I am going to make this suggestion, avoid the Color Management route to solve this problem. You may find yourself getting nowhere trying to wrap your head around the concepts of color management, application color settings, profiles, embedding profiles, etc. In Illustrator, switch to CMYK color mode. And then accomplish global color changes by selecting like color elements and applying the desired color.
I checked the original file in Illustrator, and it was still in RGB mode. However, I saved it in CMYK and imported it back into InDesign, but the Separations Preview reads the same numbers as before. Will it not convert if the file was created in RGB? Again, I don't know how the files were saved originally in terms of color...they were just exported from my CAD software.
What is the best way to save a file without embedded profiles? I have been importing the drawings directly from illustrator as .ai files....in order to save without profiles does it have to be a .pdf? Also, what numbers should I see in the Separations Preview - approximately the same values for all four?
Thank you again for all the help. I have been reading about color management online for a week....and I think I only confused myself more. This discussion has been great!
I am beginning to think this is the best way...Color Management has been pretty frustrating so far. The only issue is that the drawings are actually quite intricate, with a wide range of grays representing lines that are farther away. And there are eight drawings that I would have to do this to....so I would like to save some work if at all possible.
In any case, thank you very much for the suggestion...I may end up going this route, and next time I will be better informed!
When you converted from RGB to CMYK, if you select one of the gray lines, what colors are listed?
This would be a pretty simple fix, as Jeffrey suggests, just select the line, then select the same stroke color to get them all, and change to a percentage of K only.
The following colors are listed when I use the CMYK fader:
With the RGB fader:
With the Grayscale fader:
These are the same values as before....Is there more to conversion than just changing to "CMYK Color" under File > Document Color Mode?
I will probably just spend some time to go through and change the colors as Jeffrey suggested...I'm just trying to understand a bit more how this works.
Thank you again for your time!
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OK, lets back up a bit.
If the file is in RGB mode, the only numbers that really count are the RGB, and it seems pretty evident that that's the case. The other numbers are simply waht the RGB values would convert to, IF the file were converted to one of those other modes. If the file were in CMYK now, and the line were really gray made only from black ink, the value of the gray slider would be the same as the K value in the CMYK sliders, and there would be 0 in C, M and Y.
RGB colors, even blacks and grays, always convert to 4-color mixes when going to CMYK. In order to fix this, you are going to have to move these drawings out of RGB space. If they have colors other than black and grays, then you should change the color mode of the files to CMYK, then fix the grays. If they are only grayscale, you can convert to CMYK mode and use Edit > Colors > convert to graysclae to do it all in one step in Illustrator.
Ahhhh....Okay. That makes sense. Thank you very much for the information! Most of the drawings are completely grayscale, so I should be able to use the "Convert to Grayscale" function. I am quite sure that this will print correctly with Lulu....In any case, I will post here with my results when I get the book next week. Thank you again for all the time and patience today....I now understand a bit more about color management in InDesign.