Shooting at 72 dpi

<p>please can anyone explain why my Canon 40D and Canon 50D are shooting my images at 72 dpi. They only shoot at 300 dpi in the raw setting, but then my file sizes are much too big. The problem came to light when I enlarged a 15M image to 16"x12" and there was evidence of pixelation and colour breakdown. Can I manually adjust these cameras to shoot at 300 dpi. All my Nikon cameras shoot at 300 dpi.</p>

<p>Thank You</p>

<p>72dpi is just a metadata tag, it means nothing. Your actual image size in the pixel dimensions.<br>

16x12 isn't very large, prints of that size should be absolutely fine. How did you enlarge the image? Interpolated on screen?</p>

<p>The tag of 72dpi is an old number in printing; about 4 centuries; it is printers points; its the original Mac tombstones monitor pitch.<br>

Just do NOT worry about the 72 number; it will be around after we are all dead and gone .<br>

Worry about what matters; ie pixels.</p>

<p>You have to set the camera's largest setting, this will give you the maximum resolution for your camera. Then use "JPG FINE" if you don't want RAW. Ignore the "dpi" output. My Canon files say 72 dpi, too, and it means nothing. This has no effect on your enlargement.</p>

<p>When I adjust image size in Photoshop, it gives little hints for changing sizes:<br>

<strong>Bicubic smoother</strong> (Best for enlargement)<br>

<strong>Bicubic sharper</strong> (Best for reduction)</p>

<p>Set your dpi to 300 in the image size window and tell it how big the print will be. It will interpolate the pixels for you. Follow up with final sharpening just before you save to print. This should take care of the resizing problems.</p>

<p>A camera doesn't "shoot" at any dpi. The pixel dimensioins are what matters, e.g. 3000 x 2000 pixels for a 6 MP camera. JPEG Large or RAW files have the same pixel dimensions, but the JPEG file will be compressed giving you a smaller file. Ignore dpi until you print.</p>

<p>If you open the image up in an image editor like Photoshop and look at the file size, you will see 72DPI is only valid if you plan to print at a size of something like 48x72 inches or larger. Crop the image to 8x10 or letter size without doing any interpolation and look at that file size setting again and I bet you'll find the image is natively around or more than 300PPI without you doing anything else.</p>

<p>You need to understand what you are seeing before deciding it's a problem.</p>

<p>You start messing with interpolation without knowing what you are doing, and to a file that probably honestly needs nothing like that done at all and you can wind up with something much worse</p>