I'm having an issue with Illustrator CS5 that I've seen mentioned in many, many forums, but I haven't found an answer that has fixed my problem.
When I use Save for Web & Devices... to create a png, it comes out in nice beautiful colors. When I use Export... or Save Selected Slices... to create a png, it comes out in very dull colors.
It seems to affect all the colors, but here's an example:
(created with Save for Web & Devices)
(created with Save Selected Slices... and identical to those created with Export...)
Also, in the dull versions the black becomes a dark gray.
Here's some info about my setup:
Finally, here's something interesting that may help with troubleshooting:
While I was exporting this with all the different settings, at one point I decided to paste two of the exported pngs into Illustrator so I could put them right next to each other and compare the colors. To my surprise, the dull exported pngs appear bright and normal when they are pasted into Illustrator.
If you can help shed some light on this, I'd appreciate it. Soon I will need to be exporting some slices, and I need the colors to come out right at that time.
Update: As suspected, the document was created in Adobe RGB (by someone else, not me). Here's an informative article that explains why my colors were coming out dull in detail: http://www.kenrockwell.com/tech/adobe-rgb.htm
I'd guess that the problem is your starting point for the document. Choose "Web" for the document type rather than Basic RGB, or be very sure the color space is sRGB and not the wider Adobe RGB. Going that route, I see no difference in the output of Export or Save for Web, and wouldn't expect to.
When you Save for Web, you don't see a problem because AI converts the color profile to sRGB while preserving the appearance.
The other setting that you should change is the Black. Always keep it at "Accurately" for display and output. You can be seriously embarrassed otherwise.
As a general rule with color profiles, don't use "Assign...". Instead use only "Convert to Profile" with either "Perceptual" or "Relative Colorimetric" chosen in the options if you need to change the color profile of a document. An Adobe RGB image assigned an sRGB color profile will appear dull, because there is no conversion involved. The color numbers are simply interpreted differently. Converting from one to the other preserves the appearance by changing the underlying numbers.