help with resolution/DPI

[jjeanjones]

Hi all,
Am new member here and enjoy photography as a hobby. Recently having troubles getting some of my images the quality needed to order as gifts, such as photo blankets/poster prints etc. I currently have 10.mp camera and getting a new 12.1mp soon isn't this adequate for large size prints? Keep getting flags that resolution too low for quality enlargements. What am I doing wrong? using highest settings on camera and have tried scanning 35mm prints at 1200 dpi and still not working, Any ideas or help would be greatly appreciated as trying to get jump start on Christmas gifts.

[dcclark]

10 MP is MORE than adequate for large prints. Heck, I've printed 6 MP and 7.1 MP images up to 18x24 before. Resolution (DPI/PPI) really doesn't matter much. The larger the print, the farther away you will be viewing it from, and so you won't notice the minor differences in quality. 1200 dpi is ridiculously high quality -- you really can't see any difference if you're above 300 dpi.

Question: where are these "flags" coming from? Most online printing services accept anything down to 100 dpi. Notice that setting the DPI in software doesn't do anything for print quality -- it's just a number stored in the file which helps software display rulers and such on your photos.

(As an interesting sidenote: my department got a "welcome to Mathematical Sciences" poster printed, with a photo of our building. It was accidentally printed from a preview image, so it was something like 12 dpi -- seriously. But it's a large poster, and from 10 feet away, you don't notice the chunkiness at all!)