Why don't my colors look the same on all computers?

Monitors are a interesting animal. You might almost get away saying that no two monitors show the same color. Have you ever gone into a store, looked at TV screens and noticed the difference in display? Sometimes the difference is between models, sometimes you can see the difference between individual units of the same model. The same is true about computer monitors. We don't normally think about it, but, it is pretty much true.

Historically, there are colors called websafe colors. Websafe colors are touted as displaying identically across all computers. Though websafe colors may not display identically across different computers, they are fairly consistant and on a single computer the colors will be consistant. There is a fundamental set of websafe set of colors and you can ask photoshop to display colors that are websafe. As monitors get better, more and more consistency exists between monitors over a wider range of colors, but, the problem still exists ... even in shades of gray.

Interestingly, for some colors, you can ask the browser to generate a color and display a photoshop picture with that theoretically identical color on it and some monitors display the colors differently. This happens even more frequently if the website is using "transparent" areas and you have png images.

Limit your colors to websafe colors and the problem decreases significantly, use random colors that you just really like and you need to be aware that not everyone will see what you see on your computer ... and colors you are expecting to be identical can require kludging to get them to match ... as you have done.

Incidently, there is another possibility. Sampling using Photoshop can return a "bad" color. It is not Photoshop's fault. Unless the color is black or white or a very pure color, Moving the sampling probe around a little and probing, sometimes you can get different results. Contrary to many peoples expectation, it can be an interesting problem to "duplicate" colors if you don't actually know the original color code.