An author friend of mine who does her own covers just got her print proof back from CreateSpace. She suffered a shock. What, in eBook, looked great, what came in through the mail was a lot different–namely darker.
Yeah. That happens. Remember: there’s a lightbulb behind the eBook cover, the light that makes your screen glow. There’s no lightbulb sandwiched into the dead-tree cover of your trade paperback or hardcover.
Solution: Raise the levels by 0% to 30%, usually, on average, about 15-20%. Lighter covers require less, dark covers require more. Then, before uploading your cover to CreateSpace, take it down to your local professional print shop and spend $15 to see if it’s how you want it.