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Hi guys,
I've recently discovered this amazing article that explains how to deal with Total Area Coverage (or TIC) for prepress issues.
The procedure is fine, effective and everything, I love it, but… recording the steps within an PS.Action doesn't work. I've done many Actions before, but here, it seems there's a problem with recording the selections, layers and so on.
I don't understand why it doesn't work and wonder whether I need to think about writing a proper script to achieve the same result or if there is another way to create that Action (more simple to use).
What do you guys think about it ?
I'm talking about this article
https://creativepro.com/reducing-total-ink-with-selective-color-adjustments-in-photoshop/
Thanks for any intake/ idea/ light or existing solution ^^
Fred
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My best advice is to ignore that piece utterly. TAC is an attribute of the ICC output profile for conversion to CMYK; get the ideal (correct) profile that defines those conditions and just use that.
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Hi,
Thanks for the answer 😉
I would have loved to agree with you, cause it would mean things could be kept simple. But it's not in our business, I'm sorry.
I understand that icc profiles are meant to deal with that kind of stuff but it would be a big mistake to blindly rely on them because of one simple question : How do they they reduce the TAC ? What if the files are in RGB, CMYK? have a dominant color etc. We could also simply use the function "Apply Color custom CMYK Profile in PS, set up 300% TAC and Bang! Done". Somethimes it "works", sometimes it kills your picture, turning blacks into bad greyish colors. Not acceptable at all. Dealing with TAC is no easy business and doing it the wrong way can definitely kill the aspect of your image.
Long story short, it's safer to handle the images manually and the article provided above is by far the best option I've found so far. The only downside of it… I can't make an PS.Action out of the the procedure
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I understand that icc profiles are meant to deal with that kind of stuff but it would be a big mistake to blindly rely on them because of one simple question : How do they they reduce the TAC ?
You do not seem to quite understand Color Management.
The TAC is applied in the conversion from the profile connection space to the target CMYK space addording to the parameters in the ICC Profile.
With RGB (and Lab obviously) to CMYK-conversions that is unproblematic. (Edit: Because the Color Space’s TAC will simply not be exceeded that way.)
With CMYK to CMYK-conversions it can be problematic because it can dirty up primary colors and make grayscale compenents 4C-gray.
(Banding can happen in both cases.)
But if CMYK-to-CMYK is a frequent task for you you may want to look into Device Link Profiles and purchase software for their creation, because they only connect one specific Color Space to one other specific Color Space.
The old Custom CMYK is best avoided altogether.
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If you work in RGB and convert to CMYK it's impossible to exceed TAC. That's when the built-in profile limitation applies.
But yes, it's easy to exceed TAC if you work in CMYK and don't watch it..
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I suppose especially in publishing one can get images and ads from various sources and some of that material may be CMYK and some of that may be the wrong CMYK … so CMYK-to-CMYK-conversions may be necessary.
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Spot on!
that is what is happening to us
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IMO, best way to convert CMYK material to another CMYK colour space is by using a color server, any CMYK > CMYK conversion in Photoshop (because it uses a 3 colour PCS) inevitably unravels the black channel which means any black only object will now be 4 colour not black. Plus it messes up in other ways
GMG make a nice color server used for exactly this purpose.
I hope this helps
neil barstow, colourmanagement net :: adobe forum volunteer:: co-author: 'getting colour right'
google me "neil barstow colourmanagement" for lots of free articles on colour management
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Exactly; CMYK to CMYK more often than not will hose black gen. The proper tools for this are Device Link Profiles.
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A Device Link Profile connects one Color Space to one other Color Space, so one may have to create specific profiles for each unwanted Color Space one receives an image/ad in.
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Hi Dain, what's good to know is that there's a seemingly undocumented procedure to use devicelink ICC profiles in Adobe Photoshop.
Of course someone has to build the device link profiles for you, in this example it shows a devicelink profile we made that converts between the Fogra 39 & Fogra 37 colour spaces. it worked well.
This was an image conversion so I did not test the preservation of the black channel.
Photoshop / Edit / Convert to Profile / click Advanced see dialog below
device link profiles are specially constructed for each conversion, so we need to know the source space (of the existing document) and the destination space (the press ICC)
Worth some testing? perhaps
Does anyone know where this "advanced" Photoshop feature is documented please?
more reading:
https://www.pdfa.org/why-devicelink-profiles-should-interest-you/
I hope this helps
neil barstow, colourmanagement net :: adobe forum volunteer:: co-author: 'getting colour right'
google me "neil barstow colourmanagement" for lots of free articles on colour management
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And for CMYK to CMYK conversions there exist Device Link Profiles which can change TAC while maintaining pure blacks, primaries, …
If you insist on the Selective Color Layer-approach you may want to cosnider using Blend if-settings instead of a Layer Mask.
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Thanks for the answers guys,
I actually didn't know about Device Link profiles. I'm definitely gonna have a look at them.
What do you mean by using Blend-ins?
would you mind telling me more about it?
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Many years ago I intended a 3-part series on the layer option blend-if sliders... And stalled after part 1!
https://web.archive.org/web/20100116171247fw_/http://members.ozemail.com.au/~binaryfx/blendif.html
Take note of the animated GIF files illustrating the text.
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Blend if-settings can make a Layer affect only certain parts of the underlying Layers’ luminance. Similar to a Layer Mask, but with drawbacks (no Filters, no Curves, … on the »Mask«) and benefits (changes in the underlying Layers do not necessitate re-creating the Layer Mask).
And one can split the Blend if-handles by alt-click-dragging them.
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...and let's not forget, per channel. Split per channel Blend if opens up a whole new world of layer blending.
I love Blend if, I don't think I have many files that don't have a Blend if applied somewhere.