There are a couple of tricky ways of shrinking images: cutting the number of colors out of GIFs, reducing the quality of JPEG compression -- but the easiest and most effective way of trimming download time is to crop.
Here you must ask yourself what the image does for your page -- What's this picture's job?
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The original image measured 400 x 600 pixels -- much too big for a web page, although the file size was just 23K. Scaling it sacrifices detail. |
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The cropped version keeps all of the detail of the original, yet emphasizes the cameraman. File size is 20K. |
One of my colleagues sent me this image for the faculty-at-work section of our web site. It's a good image, well-framed, compositionally sound, with the panorama emphasizing the wide-open-spaces of the west.
That's great for the photo, but not so good for my purposes. First, there's an awful lot of mountains. I like mountains, everybody likes mountains, but not everybody wants to wait for mountains to download. Besides, the page covers faculty-at-work, so I need the photo to emphasize Brett, the guy with the camera.
So I crop.
The result emphasizes Brett as the biggest figure in the image, and it cuts
mountains and sky (which tends to splotch in JPEG compression). Much of the
meaning of the original image remains. And I haven't lost any of the original's
detail, as I would have if I had instead scaled the image.