Web Page Design

A Round JPEG in a Square Hole

THINGS TO REMEMBER ABOUT JPEGs

JPEGs are good for photographs, continuous-tone images, images with subtle color or lighting changes.
JPEGs have millions of colors (24-bit)
JPEGs use a "lossy" compression scheme
JPEGs take longer to download than GIFs (the JPEGs have to decompress in the browser)
Don't save a JPEG image over an existing JPEG -- you'll compound the compression, and the image will look horrible

A photograph is an ideal candidate for being saved as a JPEG.

Pick yer options -- they'll vary from image to image. Some pictures can stand a lot of compression before they start to look crummy, others can't take much at all. For the Web, mine usually end up in the 3-5 range.

The three "Format Options" I don't normally worry about, and mostly keep it on "Standard." This is supposed to "minimize the amount of data loss during compression." The "Optimized" setting is supposed to "optimize image quality during compression," but at Web resolution I can't tell the difference between these two settings.

"Progressive" reveals the image in the browser with several passes (like an interlaced GIF). I don't bother with it -- I've found Progressive JPEGs to be buggy.

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