: file size after "save as"


csonni
Aug 31st, 2005, 05:11 PM
Just tried out my new Canon S2 IS- love it. I have been wondering about this for quite some time- why is it that when I save the original image ("save as") through Photoshop, after only 2 Unsharp Masks (both at 45%) the image file size jumps from 2.3 to 6.2 megs?! Even when "save as" without any post-processing, the image file size jumps at least a meg or more. Should I not be saving them in PS? What gives?

farfisa
Aug 31st, 2005, 05:26 PM
One thing is that Photoshop images don't use JPEG compression, so they store info for every pixel; the other is that Unsharp Mask sharpens the image and "creates" more detail, which is more info for photoshop to store, thereby increasing file size. Make sense?

comprehab
Aug 31st, 2005, 05:29 PM
Save the photo as a JPEG instead next time.

csonni
Aug 31st, 2005, 07:14 PM
comprehab- I save all of them as JPEG. So with PS saving "more detail", does this actually make for a better image?

ArtistSeries
Aug 31st, 2005, 09:41 PM
JPEG is"lossy" format - you loose information. Saving with a better rate will not help regain that information.
What maybe also happening in your case, is that you are saving lots of extra information.
Try "Saving for web" in Phostoshop and see if there is a difference.