I have an old version of Photoshop that won't run on my MacBook, so I decided to give some of these new Core Image image editors a try. None of them including Pixelmator, Acorn and Chocoflop were fast, even for simple tasks, and none of them were usable for larger images. I thought maybe it was unoptimized code, or whatnot... But then I tried adjusting colors for a picture in Preview. Preview beachballed on me and simply couldn't keep up with the slider movement. This was on a 3072x2304 pixel photo. What is going on here? My MacBook is maxed out with 4 GB of RAM, and I know there was plenty of free RAM, as Activity Monitor told me so. Was Preview using Core Image to do the adjustments? If so, are Core Image editing features simply unusable on a new MacBook at this point? I simply cannot understand why I cannot drag the contrast slider quickly from left to right on a Photo in Preview without getting the colorful beach ball of death each time. These are things I could do easily and quickly on my G4 eMac with Photoshop and other image editing tools.