Comparison of apples and oranges.
The two cameras are aimed at two different customers.
Here is a direct comparison:
http://snapsort.com/compare/Canon_EOS_Rebel_T2i-vs-Nikon-P510
In the hands of someone who has been taking pictures for a few years and has a knowledge of photography, either camera can produce excellent pictures.
An expensive camera is no guarantee that you will take excellent pictures.
The knowledge of the person holding the camera is more important than the camera.
If this is your first camera, it is more practical to buy a less expensive camera and spend a year just learning about photography.
Here is a place to start:
http://www.shortcourses.com/use/
Hi what should I but the nikon p510 for
$450.00 or the T2i for $799.00 with 18 - 55 is and 55 - 250 is I don't have a camera now.

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