Colors in PNG inconsistent between Windows and Mac


I have a PNG file on my Windows machine of a proposed logo that someone sketched out in PowerPoint. I am tasked with making a master version in Illustrator, and then saving various copies for web use, Word, etc.

The logo is a uniform red color, with white lettering. Simple enough.

Here's my question: When I open the PNG on my Windows machine (where I have PowerPoint) and also on my Mac (where I have Illustrator), the red shade looks darker on Windows. At first I thought it might be that my crappy Dell monitors weren't calibrated as well as my new MacBook Pro, but when I check the color with the eyedropper tool I get RGB values of (181, 10, 0) on Windows, and (188, 0, 10) on the Mac. Same PNG file, totally different colors.

What could be causing this difference? I'm not well-versed in color management profiles, is that what's tripping this up? And how do I ensure that the final logo looks the same across different devices?

EDIT: Here is a cropped portion of the PNG in question:

enter image description here

  • On Windows with Paint.NET, the uniform color shows up as (181, 10, 0)
  • On Mac OS X with Pixelmator, the uniform color shows up as (188, 0, 10)
  • On Mac OS X with Illustrator CS3, the uniform color shows up as (188, 0, 10)
  • On Mac OS X with Photoshop CS3, the uniform color shows up as (181, 10, 0)

What does it show up as on your computer?

EDIT 2 I created the PNG by taking a screenshot of the logo, with the indention of tracing it in Illustrator, so this is not a problem with PowerPoint exporting badly. The problem is with the colors in the resulting PNG file.

3/23/2011 1:46:00 PM

Before I say, "The people you're making this for couldn't see the difference if there lives depended on it".

I offer this: I think you're comparing Apples to Oranges, then trying to ask why things are different. The programs you're comparing are completely different (demographic, intended use), you shouldn't expect a seamless use between them - especially at the level you're examining color. You're also using an OS capture procedure to get your base image. I'd say your results are to be expected - they're pretty good.

enter image description here

I did what you did (screenshot the image above and opened Ps, then Ai - both were (181,10,0)). However, I did not get 181,10,0 in Ai until I chose RGB from the preferred color type from the File Menu. Place vs Open yielded different results as well.

(The color swatches above are in order as you have them in your question).

Comparing RGB values makes them seem that they're very different. Perceptually speaking, not so much.


I just caught one of your comments on @DA01 answer.

PNG retains color, JPEG is lossy...both true. BUT your OS isn't necessarily generating the highest quality/most reliable color file - it's snapping a quickie image for you. Your OS doesn't give you the option of PNG8, PNG24, DPI settings, JPG 80% quality, JPG 100% quality....all of those factor into the overall quality and portability of your file.

The screen capture wasn't built to be an industry-standard color manipulator like Ps, or Ai. When you're using those two programs your color choices become hard coded into the files (very easy to see if you create a spot color in either, then place the image into InDesign).

3/24/2011 3:14:00 AM