Canon 40D and Nikon D300 are examples of DSLR or Digital Single-lens Reflex cameras. Although Canon 40D and Nikon D300 offer much higher performance compared to other similar devices, there are still some differences between the two. The first clear-cut difference that most people would probably notice is the sensor resolution of the two cameras.
In this regard, the D300 is equipped with a 12-megapixel sensor, whereas Canon 40D comes with a sensor resolution of 10 megapixels. Although most people don’t bother about the small difference in their sensor resolution, Nikon D300 is usually preferred because of its ability to produce finer details compared to the 40D.
While Canon 40D can shoot at 6.5 fps, the Nikon D300 can only shoot at 6fps. However, the D300 can still shoot at 8 fps if it is used with an optional battery pack. In terms of cost, Nikon D300 is more expensive than Canon 40D.