CMYK document + RGB image + Selective Colour Adjustment = "Wrong" colours in print

[joe_l]

It seems to be not a bug, although this is what I thought before.

Setup:

1. CMYK document + placed RGB image (in my test case a simple fill with #ff0000)

2. Applied a Selective Colour adjustment by setting Cyan and Black both to -100% at Reds

Visual appearance fine, but not matching to the printout on a HP Colour Laserjet M751. Obviously the printout shows what has to happen with the adjustment values. BUT what "annoys" me, is the fact, that printing directly and printing from PDF differ so much.

Lessons learned: a) Don't mix colour spaces b) Don't be lazy c) Print from PDF in any case.

[stokerg]

Hi @joe_l,

Just thought i'd let you know your post hasn't been missed.   I'm currently working from home and don't have access to a printer.  I'll be back in the office on Wednesday and will do a couple of test prints and see what results i get.  Personally from just working in Tech Support, i've learnt over the years to always export to PDF and print from the PDF.  I suspect printing directly from the app is using a different route and causing the difference.  Once i can see the issue for myself from a test print, i can get more information on the issue and if this is expected or not  

[joe_l]

4 minutes ago, stokerg said:

Personally from just working in Tech Support, i've learnt over the years to always export to PDF and print from the PDF.

Normally also my route, but sometimes I am lazy. 🤦‍♂️

[joe_l]

16 hours ago, stokerg said:

Once i can see the issue for myself from a test print, i can get more information on the issue and if this is expected or not 

Made some further tests and this one cannot be expected IMO ... maybe ... possibly:

1) Rasterise the image (delete the adjustment before). Does rasterising an image convert it automatically to the document colour space?

2) Add adjustment again and print.

Result: Wrong colour.

3) Delete the adjustment and convert image to image resource. Resource manager is now showing the image has the document colour space.

4) Add adjustment again and print.

Result: Still wrong colour.

So does this mean the image still carries the "original" colour space throughout the whole process and there is no chance of changing it? Or is just the adjustment and the print engine to blame?

[Leigh]

On 7/19/2022 at 8:02 AM, joe_l said:

1) Rasterise the image (delete the adjustment before). Does rasterising an image convert it automatically to the document colour space?

Yes. 

Just wanted to let you know that we're still investigating. I'm also seeing the same issue when printing to a Canon Inkjet in the office. Changing the Colour Management settlings within the Print dialog made no difference.

[Duskstalker]

@Leighi just want to report that with my epson ET7750 i also have issues with printed colors from CMYK publisher documents.

whenever i export to PDF and print with acrobat pro, the colors are correct.

this is where i have issues:

publisher document in CMYK, pictures (jpg) in CMYK, placed (embedded or linked doesnt matter) in the document. when i print the document, no matter what i configure in the affinity publisher printer menu, i always get wrong and oversatured colors in the pictures (vectors created in publisher seem to be fine). theres something going on in the CMYK color management system. that said, all affinity apps also display CMYK clamped in the srgb colorspace, that also produces wrong CMYK screen output (especially on calibrated wide gamut displays).

printing RGB pictures in affinity photo seems to work normal or at least not as obviously broken.

if you need more infos, please just hit me up. i will provide everything you need. i can do some comparison test prints and scan or photograph them.

[Leigh]

Thanks for letting us know @Duskstalker - I will make @stokerg aware that you're also having the issue. Looks like one for the developers.