A straight-forward answer to this might be out there, but I haven't
found it yet. (All file sizes are approximations, but representative of
When saving JPEG's, the Quality drop-down menu gives you the choice of
Low, Medium, High, Maximum. Choosing Maximum gives a setting of 10.
However, you can increase the setting to 12. I've noticed that if I open
a JPEG that is, say, about 1.3mb and save it at the "default" Maximum
setting of 10, it compresses it to, say, about 900k. If I save it at the
"maximum" Maximum setting of 12, I actually end up with a larger file
than I started out with of about 3mb. Apparently it is uncompressing the
original compressed jpeg?
What's up with this, and practically speaking, should I be saving at 10
(Take it as read that I know about tif being non-lossy, and jpeg being
lossy, etc. I'm just wondering about this Photoshop jpeg Quality thing.)