My wife gave me a Canon EOS Digital Rebel XSi camera recently and I wonder how large a print I can order. I always use the highest JPEG size and quality when taking photos. When I open them in Adobe Elements 7, and check the size, the information shows 59 x 37 inches. Is it really possible to get a print that large with JPEGs from this camera? J.R.
Well, J.R., the simple answer is no. A 12-megapixel image simply does not have enough pixels for such a massive print if you expect good quality. When checking the size data in Adobe Elements, you will also note that the software indicates Resolution: 72 dpi. (The term dpi means dots per inch; think of it as pixels per square inch of a print.) That’s a very low level of resolution suitable only for images viewed on a computer monitor. You need a resolution of at least 200 dpi — and preferably 240 dpi — for a true “photo-quality” print.
Try this. Open the Size or Resize utility in your Adobe software. (Use this command to do so: Image > Resize > Image Size.) Make sure that there is no check mark in the Resample Image box. Now, change the resolution amount from 72 to 240 dpi. The software will then show you the new document size at 240 dots per inch: roughly 17.8 x 11.87 inches. Assuming that your JPEG image photo is very sharp you should be able to get an excellent print of this size. (Set the resolution to 200 dpi and the size will increase to roughly 21×14-inches; print quality may still be acceptable at that size.)
Of course, the larger the print the lower the quality will be; after all, the number of pixels per square inch gets smaller as print size gets larger. Even so, you can probably get an even larger print of good quality-perhaps up to 13 x 19 inches– from your technically excellent JPEGs. There are methods for adding pixels (called interpolation) that can allow for making much larger prints.
However, for the very best results, remain conservative as to the size of prints you order. If you want only a poster, many stores will make one for you in dimensions up to 20 x 30 inches at relatively low prices. But don’t expect true photographic quality given the extra large size and the lower quality of the paper that’s used for posters.