The Planted Tank Forum - View Single Post - Tell me about diopters aka close-up filters
View Single Post
Old 10-27-2012, 04:48 AM   #13
TickleMyElmo
Planted Tank Enthusiast
 
TickleMyElmo's Avatar
 
PTrader: (5/100%)
Join Date: Aug 2009
Location: New Jersey
Posts: 807
Default

Quote:
Originally Posted by etane View Post
Currently, I'd say I can get to within 2' of the subject. Ken Rockwell claims 1.25'.

I don't necessarily want to get up any closer to the subject. I don't mind sitting about 3-4' away from the subject. But, I want to be able to telephoto closer to the subject.
You're kinda looking at the wrong thing, its close focus AND reproduction ratio that you should be looking at. Reproduction ratio being the biggest issue.

The 17-55 has a 1:5 reproduction ratio. The lower the second number (or the closer the second number is to 1), the bigger the subject will appear.

For example, a lens with a close focus of 2.25' but a reproduction ratio of 1:2 will magnify the subject/make the subject appear larger than a lens with a 1.25' close focus but a reproduction ratio of 1:5....

Get it?
TickleMyElmo is offline   Reply With Quote