Getting Smaller File Sizes in Photoshop

[Jezebel]

To the Point

Use Photoshop's Save for Web feature instead of the regular Save or Save As... to get the highest quality jpeg avatars 20kb or less (required to upload to the forum). This feature is available in Photoshop 5 and above.

Where Are They?
(In Windows)

Save For Web
File Menu: Save For Web & Devices
Keyboard Shortcut: ctrl+shift+alt+s

Save
File Menu: Save or Save As...
Keyboard Shortcuts: ctrl+s or ctrl+shift+s

Explanation and Examples

This is a 115x145 jpeg saved in Photoshop using regular Save at maximum quality. The file size is 44kb, which is well over the 20kb size limit.
http://i121.photobucket.com/albums/o223/orlathe/jpeg-maxquality.jpg

This is the same jpeg saved using regular Save at the lowest quality. Not only does it look terrible, but it is still too large to upload at 24kb. Even if you do manage to find an image that will go below 20kb using Photoshop's regular jpeg save feature, it's going to be full of compression artifacts. Why save it like this when it is not any more difficult to save it at higher quality with a smaller file size?
http://i121.photobucket.com/albums/o223/orlathe/jpeg-lowquality.jpg


This is the same image saved using Photoshop's Save for Web feature at maximum quality. It's still slightly too large at 24kb, but we're just one minor adjustment away from getting a quality image that will work.
http://i121.photobucket.com/albums/o223/orlathe/jpeg-sfwmax.jpg

Dragging the quality slider to 95% results in minimal quality loss and a 20kb file size. Each image is different so you may need to experiment with dragging the slider until the size goes below 20kb. This image will upload to the forum and doesn't look much worse than the maximum quality jpeg I started with.
http://i121.photobucket.com/albums/o223/orlathe/jpeg-sfw95.jpg

[ScurvyRose]

Is that a picture of you?

[Jezebel]

Is that a picture of you?
No.

[Karamazov]

The quality of the avatars I've submitted weren't that bad, were they?

[EarthBound]

Also note that for black and white images, .gif files work just fine and drastically cut file sizes without the above-demonstrated ghosting.

[jhpark]

This actually helped me in Photoshop Elements as well, as I was sliding the quality slider to 0 and still not getting a small enough file. Kind of silly for them to segregate whatever algorithm generates this small file size under a separate save as, but whatever...