The EOS 50D features a newly-designed 15.1-megapixel APS-C sized CMOS sensor which is capable of recording up to 4752 x 3168 pixels with full 14-bit A/D conversion for extremely fine tonal gradation. Ready to capture images in an instant, the sensor is designed to work with Canon's EF and EF-S lenses with a conversion factor of 1.6x. It's capable of recording at sensitivities previously too noisy for shooting in low light or subjects in motion. With a maximum ISO rating of 12800 combined with a 4-level High ISO speed noise reduction function, images that would have been impossible without the use of a strobe or flash become simple to record.
With some lenses, the peripheral AF points may become sensitive to either vertical or horizontal lines (they will not function as cross-type AF points). These lenses are: EF 35-80mm f/4-5.6, EF 35-80mm f/4-5.6 II, EF 35-80mm f/4-5.6 III, EF 35-80mm f/4-5.6 USM, EF 35-105mm f/4.5-5.6, EF 35-105mm f/4.5-5.6 USM, EF 80-200mm f/4.5-5.6 II, EF80-200 f/4.5-5.6 USM.