How many JPEG cycles?

Bodley

I'm saving for potential print sizes varying from 4x6 to 16x20. In PSCS saving at JPEG 10, how many open-modify-save cycles does it take to degrade the photo.

Greg

BigAl

One (jpeg is a lossy compression technique).

Rather save in PS's native format until you're finished, then create the final jpeg.

regards
alan

Shay Stephens

JPG is not evil
No offense intended to anyone, but there is a lot of misinformation floating around when it comes to jpg compression and quality. The situation is not nearly as bad as the detractors make it out to be. You can safely recompress images using jpg level 10 a handful of times before any noticeable changes occur to the image.

Case in point, exhibit A and B:

Exhibit A - A first generation jpg image (100% crop) showing fine detail.


Exhibit B - A sixth generation jpg of the same image.


Now if you will be so kind as to load the first generation image into your image editor and then load the sixth generation image on top of that so you can blink test them, you will see that very little changes between the two (you might want to zoom in 200% or more).

I dare say one could open and resave many more times before an image would degrade sufficiently to be noticed by the average person.

Bodley wrote:

I'm saving for potential print sizes varying from 4x6 to 16x20. In PSCS saving at JPEG 10, how many open-modify-save cycles does it take to degrade the photo.

Greg

dragon300zx

Shays right.

JPG isn't as bad as it is made out to be. In the olden days you would notice it more and it was bad because the images you started out with sucked. They weren't the quality of the images we have today. Today you won't notice that much unless you really screw around alot.