11-03-2009, 12:10 AM
|
 |
Gear Geek Girl
|
|
Join Date: Jan 2007
Location: San Diego, CA
Posts: 8,613
|
|
Only if the 100 isn't getting you close enough. It won't affect sharpness: an extension tube is just a hollow tube without any glass elements, but it will affect the amount of light coming in and your ability to focus to infinity.
|