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Topic: Global Change: Convert to Color Space  (Read 437 times) previous topic - next topic

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  • Joe
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Re: Global Change: Convert to Color Space
Reply #15
So would the Default Settings be considered horrible? Cause that's what's being used here, much as I think it's wrong.

Default settings are almost as bad as color management being turned off. In PitStop set the color profiles that you use in Photoshop/InDesign/Illustrator/Acrobat. Whatever you do; don't turn them off.

I might agree with that if all we used Pitstop for was converting RGB images to CMYK, But we rarely convert images from one color space to another in Acrobat and we prefer using whichever profile gives the best results when we do convert anything. And if you do convert anything with 100% black text to gray you really are going to get gray instead of black with anything other than having color management turned off. Using default settings or any color management profiles for everything is not a good thing. The operator should always use whatever achieves the best result for any given subject matter.

 Best result no matter what the intended output intent is? You should use the right profile, which may or may not be a canned profile. Another benefit of using a good profile from you data is consistent separations. Meaning the separations are done in a consistent way with a consistent dot gain/curves, G/UCR, white point, TAC, etc. Consistency is the key.

Black type converting to gray is a strange one. There is little reason to convert K of CMYK or separation black to device gray unless your black & white printer has a problem interpreting K of CMYK or separation black as a black click. And even then, the problem is in PitStop and its color conversions. Here it would be better to use the remap color function to remap the channel to device gray rather than to convert.

In this case callas still does it better even though they use the same LittleCMS engine. It's not the engine, it's the logic running it.

The text I am referring too is usually 100% K but just happens to be on a page that needs to be converted to B&W. The 100% K turns to around 85% - 90% black unless you turn color management off.

As far the output devices we don't use any kind of proofers. We only output one-bits tiffs for the platesetters and we have adjustment curves and dot gain curves for each press. But we still do not do any kind of manual conversion between color spaces for images as we let Prinergy do all of that during refine. The conversions we do in Pitstop are usually just color to grayscale and truthfully none of the built in profiles do a good job at that. And having CM turned off doesn't do a great job converting images to gray either. Hence we get close with whatever profile looks best and then adjust it from there with curves or brightness/contrast with Pitstop.
Mac OS 10.12 Sierra | Prinergy 7.5 | Adobe Creative Cloud 2017 | Two Luscher XPose 160 CTP units

Prepress: One who does precision guess work based on unreliable data provided by those of questionable knowledge.

  • mattbeals
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Re: Global Change: Convert to Color Space
Reply #16
The problem of the black type going to 85% is because of the max black in the ICC profile you are using. If you are using an ICC profile with a 85% max black you're probably using SWOP v2; the extracted black channel from that profile; one of the dot gain profiles; or one of the gamma profiles.

Best to make your own 0% dot gain gray profile with a max K of 100, then save that profile out of Photoshop and use that for your gray profile. But you shouldn't have to tinker with it for a black click. Understandably with some RIP's/engines you do need to do this. That's where the remap comes in handy; it's not a color conversion that happens in the traditional way through the CMS.
Matt Beals

Everything I say is my own personal opinion and has nothing to do with my employer or their views.

  • DigiCorn
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Re: Global Change: Convert to Color Space
Reply #17
Once you go black, you'll never go back
Peon/Cog

"In wine there is wisdom, in beer there is Freedom, in water there is bacteria."
― Benjamin Franklin

"Always do sober what you said you'd do drunk. That will teach you to keep your mouth shut."
― Ernest Hemingway

Re: Global Change: Convert to Color Space
Reply #18
Quote
The conversions we do in Pitstop are usually just color to grayscale and truthfully none of the built in profiles do a good job at that. And having CM turned off doesn't do a great job converting images to gray either. Hence we get close with whatever profile looks best and then adjust it from there with curves or brightness/contrast with Pitstop.

I'm pretty sure that one could build the action list to turn CM off and convert everything that is not an image, then turn CM back on and convert only the images... However remapping is often the better approach if you don't wish to affect values.

The March 2015 webex workshop covered grayscale conversions/mapping in depth:
https://www.linkedin.com/groups/6801080/6801080-6006090175053119488

  • Joe
  • [*][*][*][*][*]
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  • Master of Nothing
Re: Global Change: Convert to Color Space
Reply #19
Quote
The conversions we do in Pitstop are usually just color to grayscale and truthfully none of the built in profiles do a good job at that. And having CM turned off doesn't do a great job converting images to gray either. Hence we get close with whatever profile looks best and then adjust it from there with curves or brightness/contrast with Pitstop.

I'm pretty sure that one could build the action list to turn CM off and convert everything that is not an image, then turn CM back on and convert only the images... However remapping is often the better approach if you don't wish to affect values.

The March 2015 webex workshop covered grayscale conversions/mapping in depth:
https://www.linkedin.com/groups/6801080/6801080-6006090175053119488

Yes I was at the webex. Just haven't gotten around to trying those things yet.
Mac OS 10.12 Sierra | Prinergy 7.5 | Adobe Creative Cloud 2017 | Two Luscher XPose 160 CTP units

Prepress: One who does precision guess work based on unreliable data provided by those of questionable knowledge.