I would like to take pictures and use it as a wallpaper for my 27" iMac and so the highest resolution is 2560 x 1440. My question is, is there a specific type of camera I should buy and use to get that high resolution? I'm thinking of getting the new Sony Nex but I'm not sure and I can only afford cameras less than $1,000. Sorry for the ignorance, I'm new to the digital photography and I just bought the 27" iMac and loving it! Any help or suggestions will be greatly appreciated. Thanks. 