Posting a PM reply with similar question, it may help others on similar issue.
Hi there,
Sorry to bother you, just like to enquire from the seniors here. Before sending your photos to the photo shop what sizes do you guys resize them to first? in terms of pixel ?
Thanks in advance!
Regards,
depends on what paper size are you printing it, there are two things to consider, #1 image ratio and paper size ratio, #2 resolution.
#1, you are using a canon 450D, the image ratio is 2:3, so if you print a 4R (4"x6") photos, S8R (8"x12"), since the paper size having the same ratio, you need not re crop your image, but if you want to print other paper size like 5R (5"x7"), or 8R (8"x10"), you need to crop it yourself before you send it for print, altho the lab can crop it for you, but it may not in the way you want it.
#2, the minimum requirement for decent quality printing is 250ppi, usually we give 300ppi for easy calculation. so a 4R (4"x6") photo, you need to have 1200x1800pixel, a S8R (8"x12") you need 2400x3600pixel, you can give higher than 300ppi, for an example, you can send a original large jpg to print a 4R, but you can't give lower than 250ppi. the photo it will be pixelated.
hope this help.
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