Photoshop Compression Bloat.
I just created twenty-five square JPEG thumbnails, 50 pixels wide, through a batch process in Photoshop CS. Each thumbnail should be an extremely small image once completed. Each thumbnail, however, averaged 40-50K in size, which is unbelievably huge. (Again, this is a 50x50 pixel image!) I re-did the batch and changed the JPEG compression settings to low quality. The bloated file size did not change. Instead of a folder of 25 images that should have totaled around 125K, I ended up with a folder 10 times that amount, at around 1 MB.
Obviously something was wrong, so I re-created the batch using ImageReady. It compressed the images correctly; each individual thumbnail was less than 10% the size of the corresponding thumbnail created through Photoshop.
This brief contact with ImageReady (I haven’t used the program for web-related work since I switched to Fireworks several years ago) left me with several questions.
Why do batch actions in Photoshop royally suck as compared to the same batch actions in ImageReady? (ImageReady’s options and settings are intuitive and easy to understand; Photoshop most definitely is the opposite.)
Why does compression and optimization, as in my case above, differ so greatly between the two programs?
Why does ImageReady even exist? Why not just make it part of Photoshop? It doesn’t seem like such a problem from a UI standpoint. Add a few dialogs (Optimize et. al) and perhaps a “web-mode” if the screen gets too cluttered, and you’re done.

Photoshop sometimes add some “extra-meta-data” into JPEG. Use ‘Save for web’ instead of ‘Save as’ and you receive much smaller file.
Posted by: dgx at June 13, 2005 05:14 PM