Alchemist

Don’t use mod_pagespeed (with the default settings! see below for more info) or Smush it if you care at all about how your pictures look.

So, in looking around at some nifty solutions to speed up page rendering and web serving in general, I came across mod_pagespeed and smush.it, both claiming to provide all sorts of wonderful optimizations, specifically, losslessly compressing images. All of their other claims aside, the particular claim regarding lossless image optimization is a lie. A damned lie. The “optimized” images look like washed out crap, at least using the default optimization settings for both systems.

Smush.it claims it’s optimization is lossless, which is clearly not true. Mod_pagespeed lists lossy compression as a risk in their documentation. Points off for me for failing to RTFM.

Mouse over the images below to see just how bad the optimized versions are.

from mod_pagespeed

From Smush It:

Update from @jmarantz: Try ‘ModPagespeedDisableFilters rewrite_images’ or ‘ModPagespeedDisallow *.jp*g’ to turn off lossy compression.

Will do. Thanks for the note.