The pictures that come directly from my digital cameras are huge -- something like 45 inches by 34 at a resolution of 72 dpi. If I reduce them to 12 by 9, they fit reasonably well on the screen (at 72 dpi) and still look good but the files are about 1/15 as big.

As far as I can remember, if I PM a 12 x 9 image it stays somewhere around that size but if I view it in my album or post it to a Social Group, something (I don't know if it's my browser or PC) insists on resizing it considerably smaller than that as soon it displays completely. When I've wanted to see an image in its original size I've been known to freeze it by clicking the Stop button when about 95% of the image is displayed. So far I've been lucky; the details I've most wanted to see haven't been in the bottom 5% of the picture.

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I trust that people outside the US are still on speaking terms with inches (2.54 cm) so I can get away with not translating all this into metric units.