Could you post the image in question and maybe a scan/photograph of the printed result?
Was the image part of a page in a design application? Could it have been affected by overlying elements?
On what printer are you printing? Waht are your color management settings?
…some casual printing place.…
Well, that doesn't help anyone who might want to answer your question, does it?
The background black pixels in that screen shot are all identical:
R = 1
G = 1
B = 1
except for a thin 0,0,0 frame around the color panel.
The black in the color swatch inside the color panel is 3,0,0.
I went to a place called officeworks in epping if it helps.they do printing.
but i dont know what settings they used.does this help?
What print process (offset, inkjet, …)?
And the screenshot really does not provide a lot of help, could you post the image (lores or section) and a photograph of the printed result where on can discern the two different colors?
am i allowed to post an image from the inernet here btw?
You are making it impossible for anyone to help in any way.
The web site of your print shop says they generate "Kodak quality prints". For the process it was a blunder for you to convert your image to CMYK. Whatever possessed you?
They also offer large posters, and I'm guessing that means large-format inkjet printers, for which RGB images are also expected, and CMYK would be totally inaproppriate there too.
The image you posted tells me nothing, it just makes me wonder what you are trying to describe.
You can post a link to any Internet image or site here, sure.
ok i hope this image is big enough so you may see the difference with the black variations.
clicking with the eyedropper tool on both black background give it the same cmyk value.
but in the print version of this,i can see the right side of image another black variation.
if you click onto the picture you can see the black background has a difference.
If one brightens the image significantly (with Curver for example) the borders do become noticeable.
C i must tell u that these are yuo seperate images,batman is a photo from the internet.and the right hand side is a layer filled with black.
so which is the best way to blend these two and get a black that will unite these 2 layers?
For starters make the added black area the same black as in the image.
Other options would be softening the mask of the image or even using Blend if-settings to hide its blackest parts.