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Old 2008-05-15, 3:42pm
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Jason Jason is offline
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Join Date: Sep 17, 2004
Location: Gilbert, AZ, USA
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First off it looks like you used Adobe Photoshop to create that sample file. Apologies if I was incorrect.

The thing that Photoshop calls "resolution" that you have set to 72 refers to the number of pixels per inch. For a jpeg image that you are posting on the web, that number is largely irrelevant and does not affect the file size (which is the limit you are hitting). There are two main things that affect the file size of a jpeg file. One is the number of pixels (width x height) and the other is the compression level, or quality. The higher the quality setting, the better the picture looks but the larger the file ends up being. Another thing that can affect filesize is something called meta data. It is extra information that is stored in the file that isn't directly used to reproduce the image itself. One example of this extra info is EXIF information that most digital cameras store in files to indicate things like the shutter speed, aperture, flash settings, etc. Photoshop also likes to stick lots of extra info in files. Sometimes it will even store thumbnails of the image for quick thumbnail viewings.[*] For large multi-megabyte images, this extra metadata represents a small percentage of the file's size. But for small images with a specific audience of the web, this extra info can take a considerable amount of precious space in your file, and is also not useful. Luckily, Photoshop has a feature specifically to address your issue. Open up the original version of your pic, then resize it down to something bigger like 350x350. Now go File->Save For Web. Make sure the file type is set to JPEG and not GIF. You should now see a preview of the file with the file size in the lower left corner. You can now play with the quality setting slider to see in realtime how changing the quality affects both the file size and the image quality (set the quality down to zero so you can see the extreme end of how bad your pic can look.. but it will also shrink it down in the neighborhood of 10KB). With this Save for Web option, you should be able to get your images down below our file size limit while still keeping the dimensions (the pixel resolution) higher. You'll also no longer be publishing hidden info about your pics.

[*] as an interesting aside, there have been instances in the past where photoshop doesn't regenerate this thumbnail when resaving a file. One famous instance of this happened when a television personality had some nude photos taken. She then cropped out the nudity and posted the G-rated resulting files on her website. Several techies discovered that embedded in the files were thumbnail images of the original uncropped nude shots of her, causing her some embarassment.
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