GIMP - Softproofing - Printer Profile?

First of all, I callibrated and profiled my monitor with a Spyder3Pro. Then a Costco print came out about 40% darker than my monitor image. Next, I downloaded my local Costco’s printer profile. Now, when I either softproof or assign the profile to my image, I would expect the monitor image to become about 40% darker, but that’s not what happens. The monitor image gets about 20% lighter. What’s going on?

Also, Costco told me to embed the printer profile within the image file, but I found comments on the internet saying you should never embed the profile in the image file. In my mind, it seems you should not embed the profile, the only purpose of downloading the profile is to see on my monitor what the Costco print will look like.

Where am I going wrong with any of this?

I really need to solve this print color problem ASAP, because I have a chance to start selling poster size prints of my blender creations.

I told Costco I plan to sell prints they make for me, and the Costco guy is being very helpful by not charging me for test prints (12x18 inch). For each new Blender creation, I must go through 1, 2, or maybe 3 test prints to get the color, brightness, and contrast just the way I want. I would rather not have to do it this way. It would be much better if I had confidence that what I see on my monitor will be what the Costco print will look like, but as you can see from the first part of this thread, I’m not there, yet and I need your help!!!


Set your RGB profile to None. This is for your working color space, and using your printer profile here will really screw things up. This is for if you are working in something other than sRGB color space. AdobeRGB is a good example of a working color space.

Also, turn on the “Color Management Filter”