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I have a Canon Rebel XS that I bought approx. 5 years ago. Just recently I noticed that I am not getting 3 frames per second anymore. (It was definitely getting 3 before.)
I shoot in the the large JPG format (not RAW) and I use a SanDisk Ultra SDHC 16GB memory card. (The speed does not increase if I shoot in small JPEG.)
I did some tests to see what I was actually getting. In manual, 1/500, f/5.6, auto focus off and continuous shooting mode; I'm shooting about 0.91 frames/second. Not cool.
Any ideas why this might be happening?