> Sometimes printer drivers won't use the black cartridge to print photos/graphics.
> Only for text. So for color photos it makes dark colors (including black) by mixing
> the other colors. And you could get gross looking pictures as a result
> You might want to check the printer settings in paint.net for anything that might
> cause this kind of issue, like:
> (1) Is the app doing color management? Maybe try to let the printer manage colors.
> Photoshop has this.
> (2) Is there a setting in the printer driver to explicitly tell it to use the black
> cart on photos? Maybe enable it.
> (3) Did the paper settings somehow get messed up? The amount of ink it puts down is
> tied to paper settings so if you get it wrong...
Note the issue is either paint.net or paint.net not liking Canon printers. You've pretty much duplicated the unhelpful answers:
1) There's no suggestion of settings for paint.net that would fix this, or where such settings might be.
2) The printer works fine when other apps print the image.
3) Both apps send the image to the same printer dialog before it is printed.