If you are an Aperture users, and you have tried to apply a transparent watermark to your image, only to find out that it gets exported as a blackbox, pull your hair out no longer. I had been having this trouble for some time, and most of the posts that I could find seem to think that people don’t know how to make transparent PSD files, or tiff’s, or that it is hit and miss whether your Mac will work or not.
Well the solution seems to be even easier than that, maybe, it has to do with the colorsync profile that your Mac is using. Mine for instance was using a custom color profile, that was made by a Pantone Huey (color correcting device). Perhaps you just picked something different that you liked? Well if you are getting the black boxes then close Aperture, switch to Adobe RGB 1998 and re-open and export in Aperture. Viola! That should get rid of the blackbox issues.
If it doesn’t fix it for you then save the Watermark you are using as a PNG file, set back up Aperture and with the Adobe profile export again. This should fix it for sure. I really hope that Apple fixes this bug, it seems that most real Photographers (amateurs or otherwise) are going to use the Watermark feature AND a custom color profile. This is a major oversight.
…Speechless.
I was in the same situation as you. Looking for this answer was not easy. BUT THANK YOU for posting!!! Honestly, you’ve made my day!