Black image on a black box don't match

[mrsubtraction]

I have an image of a person silhouetted against a black background. The image itself is grayscale and I've made sure the black parts are 100% black.

When I place this image against a black background in InDesign, the two different black backgrounds look different. I don't understand why, or how to fix this.

I'm printing this on an at-home laser printer and the blacks are showing up as different tones. But even when I export the layout as a PDF, you can see different blacks in the resulting PDF.

Any help would be appreciated!

[Derek Cross]

Open the image in Photoshop and sample the black part of the image with the Eyedropper tool, add the additional bacground and colour it with the new black you've sampled from the image, then Place it as a PSD file in InDesign.

[mrsubtraction]

That worked, thank you Derek. I wish I could get the actual spot black in InDesign to match the image black though. This seems like an unnecessary workaround. 

[Brad @ Roaring Mouse]

Your background colour is a simple box defined as 0C 0M 0Y 100K

Your image, although greyscale, has an assigned ICC profile (Generic Grey Gamma 2.2)

What is happening is that your image is being color managed and converted to CMYK according to your Color Settings and Color Management policies, converting it to a mix of CMYK, while your box is being left alone.

What are your specific Color settings? and what have you used for PDF export re: Output tab?

If you are printing directly from InDesign, what are the Color Management settings in the print dialog?

Is your printer B/w or color? Postscript/non-PS?

The fix may be a simple change in your export settings.

[mrsubtraction]

Thanks for the response Brad.

I tried going into the image doc in Photoshop and setting Assign Profile > Don't Coolor Manage.

In InDesign, I have Appearance of Black set as Output All Blacks as Rich Black. I tried setting it to Output All Blacks Accurately too.

To generate the PDF I'm using InDesign's Export feature and selecting Adobe PDF as the output type.

My printer is a black and white HP LaserJet Pro. Printing directly from InDesign (as well as printing from the output PDF via Preview app on macOS) produces the same result: two different blacks.

So I'm a bit stumped. Everything I try produces the same result. Any further help would be much appreciated!

[Brad @ Roaring Mouse]

"My printer is a black and white HP LaserJet Pro"

Specifically, which model? It makes a difference if you are printing to a Postscript driver or a non-PS (RGB-based) printer.

When printingh directly from InDesign, what does your print dialog show in the Color Mangement section?... 

Also: when you export a PDF, which setting are you using? specifically in the Output section:

 

[mrsubtraction]

My laser printer is an HP LaserJet Pro M201dw. I believe it's a PostScript printer. 

Here are screenshots of my InDesign print dialog…

And the Export dialog…

Is that helpful? Thanks again.

[Brad @ Roaring Mouse]

I've taken a look at the driver for your printer, and it is a PS-capable driver, but for some reason its PPD is not showing up in your Print Dialog, so i'm wondering if you don't have a correct driver installed.

 

Otherwise,whatever you have installed is assuming RGB, so the answer for now (as others have said) is to make sure you have changed your ID Preference for Blacks to Print Rich Blacks is your best bet so it forces a more pure RGB Black.

BTW: I printed your "Troubleshooter" file to the PS driver for your printer and it worked perfectly; both the background and image came out only on the Black layer as they should have.

[Brad @ Roaring Mouse]

Also: what is your setting for Handling of Blacks in ID's prefs?

[Brad @ Roaring Mouse]

The other thing you could do is to remove the profile from the image in Photoshop (Assign Profile > Don't Color Manage)

[Dave Creamer of IDEAS]

Is your image truly grayscale or and RGB/CMYK image with color removed?

[mrsubtraction]

It's truly grayscale. It's set to Image > Mode > Grayscale.

I'm stumped.

[rob day]

I'm stumped.

Hi @mrsubtraction , Try turning on Overprint/Separation Preview:

[rob day]

My printer is a black and white HP LaserJet Pro. Printing directly from InDesign (as well as printing from the output PDF via Preview app on macOS) produces the same result: two different blacks.

Also, if the final output is to your HP Laserjet (not an offset press), set your Appearance of Black Prefs to Rich Black:

And then set the Export>Output>Destination to Document RGB with Simulate Overprint turned on:

If that doesn’t work could you share the sample ID and PSD files?

[mrsubtraction]

I didn't have the same color profiles but setting it to Acrobat 4 compatibility and turning Simulate Overprint has definitely improved the situation. The problem is that now there's a very fine stroke at the edge of the image, regardless of how I crop it in the frame. I'm attaching a PDF here for demo purposes as well as the source files. Thank you so much for looking into this!

[mrsubtraction]

When I preview the PDF that I attached in that reply, the "very fine stroke" doesn't show up. So I'm attaching here a screen grab of what the PDF looks like in Preview. That stroke also shows up when I print it on my HP LaserJet, FWIW.

[rob day]

The stroke is being caused by the compression settings—the image is getting downsampled and compressed resulting in the fringe pixels. Either mask the image with its parent frame or turn off downsampling and compression.

[Dave Creamer of IDEAS]

Check the following:

Separations in InDesign (Window>Output>Separations),

Separations in Acrobat Pro (Print Production tools>Output Preview).

The image is getting converted to color along the way. With the DIRECT Selection tool, select the image (not the frame) and see if a color has been applied to it or the background.

[rob day]

The image is getting converted to color along the way.

Hi @Dave Creamer of IDEAS , I’m not sure what InDesign Export settings @mrsubtraction used but if you check the Sample.pdf with Acrobat’s Object Inspector, the background and image exported unchanged—the background as Device CMYK and the image as profiled Grayscale. A composite printer would interpet the blacks as different colors.

[Dave Creamer of IDEAS]

What would cause the color breakdown? The numbers look like a Photoshop black conversion.

The background shows properly as 100K. 

[rob day]

What would cause the color breakdown?

The image in the PDF is a Grayscale with an embedded profile, so with Coated GRACoL set as your Simulation profile the image would convert from the Gamma 2.2 gray profile to Coated GRACoL CMYK, which would always convert to 4-color (try it in Photoshop).

I’m actually not sure how the PDF’s Grayscale image gets a embedded profile out of InDesign? All of the PDF/X presets put grayscales on the CMYK black plate, so grayscales export as Device gray or Device CMYK (no profile) and would stay on the black plate. Maybe @mrsubtraction could let us know what Export preset was used?

[mrsubtraction]

@rob day This is a bit beyond my depth but here is a screen grab of the Export dialog box as I used it. Does it offer any clues?

[rob day]

Does it offer any clues?

Strange, I can’t replicate your export that included the Gray Gamma 2.2 profile. Tried your setting in CC2021, and CC2024 and both exported the expected Device Gray, which displays and prints the image black and the background black as the same color.