Bandwidth usage with Levels

[mikel]

I have found that on our recently launched Levels site (using image machine for the first time), it is taking original images and creating different size images (which I knew it would do, supposedly optimizing them to make page loads faster). The problem is, in all cases I can find, the smaller "optimized image" is 2-5 times larger than the original image. Here are some examples.

Original 640x400 image is 17.6k (prod code ZL2004)
Optimized 540x338 image is 73.1k

Original 640x400 image is 21.6k (prod code ZL3004)
Optimized 540x338 image is 77.5k

Original 570x356 image is 39.3k (prod code SC1235)
Optimized 540x337 image is 123.8k

Yowza. This isn't good. Is there a setting somewhere to help with this? This could definitely impact bandwidth usage substantially, especially with thousands of products.

I guess one option would be to download them and run them through an image optimization program.

[koala]

Your last sentence is what I've been doing. Not only are they oversized, they're not progressive JPG's either.

[Matt Zimmermann]

You can adjust the JPEG Image Quality if you want within Domain Settings; by default I believe it is set to 80%.

[mikel]

Matt, that's a huge help. Ours was at 100%. Is there an optimal setting you've found? On the originals we upload, we typically save for web in photoshop at about 35%-40% or so. I'm guessing we'd want this setting in the 60% range? Or would the 35%-40% range be ok?

Now the big question. Is there an easy way to redo all of our images based on new settings? I downloaded a few, did new save as to give them new dates, uploaded them, used Image Management to check for updated images and it optimized them well but would rather not do that with thousands of images if I can help it. Would be nice if there is an easy cheat.

Lastly, a warning to anyone changing this in Domain Settings. When I changed ours, our site went dead. As it turns out, updating the Domain Settings tab can modify and save your htaccess file, in our case, in not a good way. It took a while to find what the cause was so we were down about 20 minutes but after finding it and restoring a backup of our htaccess file, I was able to replicate it by doing it again (and immediately restoring the htaccess file again). I'll be keeping an updated backup of our htaccess file handy at all times. That was just weird.

[Matt Zimmermann]

60% should be a good setting. If you have the Image Management module active, you can go in there, select all image [CTRL/CMD + A], and select Delete Resized. After doing that, the images will be regenerated when pages are visited.

[mikel]

Matt, thanks again. This is a huge deal. I can't believe I never saw that setting and its relationship to Image Machine and Image Management in any of the documentation. I ended up settling on 80% and am pretty happy with the image sizes and quality there.