matching paint

hi,
I am having a hard time matching the paint on parts chopped, especially when the original has a nice glossy shine to it and the donor is kinda flat... any techniques or whats the best way to match paint??
also I was working on a pic for a contest that had the rear of a yellow Porsche on the road... i forgot what website its from and I want to upload it before the contest ends... any info would be appreciated...
this forum rocks btw!!!!!:D

matching stuff is much trial and error mix combinations of techneques ie colour adj and hue, then abit of brightness & contrast

a little noise over the final image will take the drawn/airbrush look out

photo-chop.com is the site with the yellow porsche dead line is 1st jan this forum will rock when theres more users

as for matt and glossy finishes that you may have to adj by hand ie ad reflection to bits or remove gloss from the others

thanks a mill Zammo....