How to preserved black text during CMYK conversion?

[orthodax]

I have a recevied a flattened ad in TIFF format which has an embedded SWOP COATED ICC profile.

This ad needs to be printed in our newspaper which use an ISOnewspaper icc profile.

Now the question is how do I convert file from SWOP COATED to ISOnewspaper while preserving the TEXT as black text only.

My current procedure is like this:

1. OPen the file as is.
2. Check the Maximum TAC via Histogram marked it with a colorsampler. (This ads goes up to 300% TAC)
3. Using Selective color, I've selected BLACK and subtracted 20% each for CMY and black unchanged.
--- i was able to bring down the TAC to 240%
4. Then I assign ISOnewspaper as a new profile.

By doing this i was able to maintain the text as black only color.

Tell me guys is this right thing to do. Or is there a better and safer way to do this.

Thanks in advance ;-)

[DCurry]

Rather than Assign your newspaer profile, it would be better to Convert to it - that way, your Total Ink Coverage would be correct from the start. Then you can go in and fix your blacks that got converted. You'll keep the overall color looking as intended and it's probably easier anyway.

If the black type is large enough, you might not even need to worry about it.

[mattbeals]

there's no easy way to do this. It depends on the profiles and the color conversion engine. PhotoShop isn't well suited for this particular process since device link profiles are best suited. Programs like Callas pdfColorConvert, Alwan CMYK Optimizer, GMG, Best Color, etc. are more suited for this.

Your work-around "works" for this particular ad and seems to work well even though I don't think that it will be a long term solution. If you want to see pdfColorConvert let me know.

[orthodax]

Thanks Matt!

Could you tell me more about this PDFcolorconvert and other programs you've mention. And could you recommend which of hem is better in terms of quality and easy to use.

I hate complicated things ;-)

Thanxs,

"Sorry if I keep on asking things, hopefully in time I could also contribute here ;-)"

[Shanavaz]

I can tell you the way, But the black texts may knock out the underlying colours. Go to Color settings > CMYK > Custom CMYK > Black generation > change to Maximum.

Convert the file to lab colour and again change to CMYK. You get all blacks in black channel.

[Joe]

Originally Posted by Shanavaz

I can tell you the way, But the black texts may knock out the underlying colours. Go to Color settings > CMYK > Custom CMYK > Black generation > change to Maximum.

Convert the file to lab colour and again change to CMYK. You get all blacks in black channel.

Yes, that works. I use it all the time but be careful. That does a Maximum Black GCR change to color images also which can drastically change the way your color images print.

[JRomano]

Originally Posted by orthodax

I have a recevied a flattened ad in TIFF format which has an embedded SWOP COATED ICC profile.

This ad needs to be printed in our newspaper which use an ISOnewspaper icc profile.

Now the question is how do I convert file from SWOP COATED to ISOnewspaper while preserving the TEXT as black text only.

My current procedure is like this:

1. OPen the file as is.
2. Check the Maximum TAC via Histogram marked it with a colorsampler. (This ads goes up to 300% TAC)
3. Using Selective color, I've selected BLACK and subtracted 20% each for CMY and black unchanged.
--- i was able to bring down the TAC to 240%
4. Then I assign ISOnewspaper as a new profile.

By doing this i was able to maintain the text as black only color.

Tell me guys is this right thing to do. Or is there a better and safer way to do this.

Thanks in advance ;-)

If you can get a mask to select the type I would Convert to your ISO Newspaper profile and then fill to history in the selected area which will put your 100% K type back to what it was originally before the conversion.

It works, sort of a pain but....it works.

We have done it for a catalog going on an uncoated stock, I would have to go back and restore all of the original black only shadows.
Fun at its best.....a fast machine helps

A color server would be the way to go if you have the money.


John

[Jezza]

Originally Posted by orthodax

"Sorry if I keep on asking things, hopefully in time I could also contribute here ;-)"

You are contributing

Like Joe says, be careful messing with GCR it can radically alter the printed piece