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PenmorLitho
03-06-2013, 06:25 AM
Hi everyone,

We've got CMW5 on a Konica C8000 and I'm trying to figure out the best way to handle blacks.

Ocassionaly we will have 100k in a vector image and 100k in a halftone image and with the source profile it converts both blacks differently. The vector image will stay black, as it should, but the grayscale image will turn 4 color.

Any suggestions? How you have your color setting setup?

Thanks

256shadesofgrey
03-07-2013, 01:56 PM
Is the whole file CMYK? Nothing special about that bitmap image?
k handling settings set to 'normal' or 'off'?
Hth

PenmorLitho
03-08-2013, 09:05 AM
Its a PDF so not totally sure how it was built. I think where it turns 4C its the image box with transparency over 100K object.

The settings are set to Pure Black on.

Lou_P
03-08-2013, 12:01 PM
You want to set Gray processing for CMYK to text./graphics/images. Also, it sounds like you have transparency present if there's a drop shadow, so process the job with APPE preferred.

~Lou

PenmorLitho
03-08-2013, 01:03 PM
You want to set Gray processing for CMYK to text./graphics/images. Also, it sounds like you have transparency present if there's a drop shadow, so process the job with APPE preferred.

~Lou

Yeah. setting the Gray Processing for CMYK to text/graphic/image works, but I've found if I've got a 4C image and some pieces happen to be equal amouts you get that 4C piece of the image to print gray only and looks strange.

I'm not sure of this APPE setting or where it is found.

So far the best result is just turning off the source profile all together.

Lou_P
03-08-2013, 05:51 PM
Setting gray for CMYK to Text/Graphics/Images only effects colors that are 0 in all channels but K. A pixel that has C=M=Y is not gray in CMYK because of gray balance - you know how 50/40/40 C/M/Y is required to get a gray on a conventional press. If you are seeing dropouts in 4C images those areas must be black only. This is unusual in a color separation but can happen if the designer did special effects in Photoshop although a good designer would always use a rich black (100K + 40 C) to get the proper appearance on a conventional press.

To enable APPE you need to turn it on in configure (avaialbe from Device Center in Command Workstation) then you will see the option to "Adobe PDF Print Engine Preferred" in the Job properties and you can turn that on.

Then remove raster and print the job again. Let us know what you find.

PenmorLitho
03-11-2013, 05:03 AM
Setting gray for CMYK to Text/Graphics/Images only effects colors that are 0 in all channels but K. A pixel that has C=M=Y is not gray in CMYK because of gray balance - you know how 50/40/40 C/M/Y is required to get a gray on a conventional press. If you are seeing dropouts in 4C images those areas must be black only. This is unusual in a color separation but can happen if the designer did special effects in Photoshop although a good designer would always use a rich black (100K + 40 C) to get the proper appearance on a conventional press.

To enable APPE you need to turn it on in configure (avaialbe from Device Center in Command Workstation) then you will see the option to "Adobe PDF Print Engine Preferred" in the Job properties and you can turn that on.

Then remove raster and print the job again. Let us know what you find.

I'm using Fiery System 9, went to the device center and into the configureation settings and I cannot find, "APPE Preferred" setting anywhere.