Distance and FL

[dicklaxt]

Is there a chart or something to use as a learning tool in deciding which lens to use,rent or buy when shooting birds ie: what would be the max footage for a keeper with a 400 or a 200 etc ,get my drift?

dick

[hollis_f]

If you're asking what focal length you'd need to use to get a frame-filling shot of a bird at a certain distance then this (http://www.tawbaware.com/maxlyons/calc.htm)is the tool you need. Scroll down to the 'Dimensional Field of View Calculator" and you can enter different FLs and subject distances and find out what sort of vertical field of view you'll get.