Comparing SX50 1200mm shot to SLR crop

While this is not exactly what you asked, I hope it helps.

I have a Panasonic G3 micro four/thirds with a 16 megapixels sensor. Took pictures early in  morning of an owl with G3 plus Lumix H-FS100/300 lens, that in full frame is 600mm equivalent. At the same time, same distance, took pics using a Canon SX40 at 840mm equivalent. Both cameras in P mode, max. zoom. G3 lens had image stabilization turned on. Shots handheld.

In the PC, I cropped The G3 pics to equal the owl image to the same size of that obtained with the SX40. SX40's general image quality (chiefly details and sharpness), while not by a huge difference, was clearly better.

Best regards.