White House Custom Colour is good, if you’re color managed (they prefer profiled files, and obviously your results will be better that way anyway). You can find them at http://whcc.com . You’ll have to sign up as a business, but they don’t ask for a tax ID number or anything. I’ve used them before and their quality is excellent. They do require you to do some test prints when you first start your account, but that helps you ensure that your color is where it needs to be. Ordering can be a bit fussy, but their new ROES java based system is much easier than the old FTP system. Shipping is built into the price and it’s fast–2 business days.
One other option would be http://mpix.com which is a division of Millers Labs. I’ve used them for some smaller prints, but I have a professional photog friend who uses them for all her prints. The quality is great as well, and base prices are a bit cheaper than WHCC (though neither is unreasonable), but MPIX charges shipping on top of base price so it’s probably a wash. If you’re satisfied with the color and don’t want them to futz with it, be sure to check the box at the end (or uncheck it, can’t remember) that you don’t want them to color correct. You can end up with over-saturated or really off colors otherwise.
One last bit if your’e interested. Both offer prints on canvas gallery wrapped/stretcher frame, which can be really stunning. I’ve not done canvas at either place, but I’ve heard the MPIX canvas quality is pretty cheap, but lots of folks have raved about WHCC’s canvas. If that’s something you’re interested in, that’s someting else to consider.
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