Just to share some basic knowledge sourced from magazine.
SENSOR FORMAT</font id=“black”>
The decision you make between using a DSLR with a crop(APS-C) or full-frame sensor is an important one. In general, full-frame sensors provide higher image quality and better low-light performance than crop sensors, due to the larger pixel size, but the difference is usually evident when closely scrutinised. What’s most important is that you try to match your choice of sensor to the type of photography you’ll be shooting.
If you predominantly use wide-angles, for instance to shoot landscapes or interiors, then a full-frame sensor is by far your best choice, although it has to be said that there are many excellent ultra wide-angle zooms now available for use with APS-C sensors. If you predominantly use moderate wide and telephoto focal lengths, for instance if you’re a portrait or wildlife photographer, then either type of sensor is suitable.
However, the increase in effective focal length of using lenses with a crop sensor provides a major advantage when shooting subjects at distance, so if you do tend to use a 55-200mm or 70-300mm lens for filling the frame with distant subjects, then a crop sensor offers distinct advantages.
LENS COMPATIBILITY</font id=“black”>
If you’ve an APS-C DSLR, bear in mind that lenses designed for this smaller sensor may not be fully compatible if you upgrade to a full-frame DSLR. Canon EF-S should not be used on its full-frame DSLRs. Nikon DX and Sony DT-series lenses can be used but the cropped image results in a reduction in resolution.
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