Thread: 500 mm lens
View Single Post
  #2  
Old 08-10-09, 11:29
Roy C's Avatar
Roy C Roy C is offline  
Senior Member
 
Join Date: Dec 2005
Location: Barnstaple, North Devon
Posts: 2,543
Default

Quote:
Originally Posted by Andrew66610 View Post
Hi all

Have been looking at lens in the magazines, see when it just says 300 or 500 etc does that mean they are fixed at that range. in which case would i be better looking at something like a 150 - 500mm.

Sorry if its a stupid question just cant quite get my head round it.

Thanks in advance.

Andrew
Depends whether you want a prime (fixed focal length) or a zoom where the focal length is variable like the 150-500mm. In general prime lens give better IQ and take converters better whereas the zoom is more flexible. For birding the very best lenses are primes but they are also more expensive. Another thing to consider is the speed of the lens, where a f2.8 is considered fast and a f5.6 is considered slow. As far as light goes a f4 lens will let in twice the amount of light that a f5.6 would but only half the amount that a f2.8 lens would give you.
Hope this helps Andrew.
__________________
Roy

MY WEB SITE
MY PHOTOSTREAM
Reply With Quote