The only real complaint you ever hear about the T7 is price and weak flash (5.2 feet).
The W7 is not bigger, but it is thicker.
It has a better flash (14.7 feet).
It has an issue where it selects a slow shutter speed for flash or low light shots. This can result in blurred photos under those conditions.
The SD500 is a wee bit smaller than the T7 but thicker, but not as thick as the W7.
The SD500 main complaint is price.
It has the best flash (16.4 feet).
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If you select either of the Sony cameras, be sure to get the Pro version of the memory stick if you plan to take 640x480 videos. The regular memory stick is too slow for 640x480 videos.
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Here is a side-by-side look at the specifications:
http://www.dpreview.com/reviews/compare_post.asp?method=sidebyside&cameras=sony_dsct7%2Csony_dscw7%2Ccanon_sd500&show=all
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i am planning to buy a digital camera...
i am confused between these three products.. i like the t7 cause its very compact, but i wonder about the image quality? for those who have it, can you help me out? if the t7 isnt goog enough, my other choices are the dsc-w7 and canon sd500, both 7 megapixel, similar, but which is which? thanks...

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