can my iPhotos which show at 72 DPI be got to 300 DPI?

DPI does not mean anything for a digital image, upping the DPI will not magically increase the resolution of a low resolution image. What counts is pixel size. How large is this image in pixels?

DPI is used in software like Photoshop when it prints an image. If you need to set it for that reason, you wil need some external software like PhotoShop, PhotoShop Elements or Gimp.

Open the image in Preview.app. Go to the menu Tools > Adjust Size . . .

When the pane opens, uncheck Resample Image and then enter the DPI you want, and click OK.

Save the image with a new name.

MtD

...or Preview. Thanks Meg the Dog. 8^)

This might help shed some light on the matter: The Myth of DPI.

OT