Some key factors to consider when buying a lens should be committed to memory.
- Buy a lens that is made by the manufacterer of your camera whenever possible.Exceptions to this rule might be made if you are buying a specialty lens that will not see a lot of use.
- Make sure that lens has an aperture rating that suits you.In other words,is the lens fast enough to handle the kind of work you will use it for?Does the lens have a floating aperture?Some zoom lenses have aperture ratings that change with the focal length.This is okay as long as you are aware of it,but you could be very disappointed if you don't investigate this aspect of a lens.
- Will the lens accept screw-in filters,and what size does it require?Buy a UV-haze filter when you buy the lens and install it right away to protect the actual lens.
- Does the lens have a retractable lens hood to block sun flare?Can you install a rubber lens hood yourself?Be advised,wide-angle lenses,like a 24mm lens,often will not allow the use of a lens hood.If a hood is used,it shows up in the picture by blacking out the corners.
- Make sure that the lens you are buying will mount on and work with your camera.