Extension Tube

[Octoshark]

I understand an extension tube allows you to focus at a closer distance, however, I am wondering if there is any sacrifice of quality in the photo by using one?

I'd like to use one for my Canon 100mm macro lens to get closer to the objects in focus.

 

[jedininja]

There is no glass in extension tubes, so you aren't adding any extra distortion. The main drawback that I have found is the light falloff as well as very slow autofocus. But if you are using a tripod and focus manually, you can still get very nice results.

 

[Octoshark]

Ok cool. Yea I have read that you have to make up for light by increasing the aperture and/or decreasing the shutter speed.

 

[Octoshark]

Does anybody know how much this extension tube will reduce the focusing distance to for my Canon 100mm? All it says is "shortens focusing distance" but doesn't say by how much:

http://www.bhphotovideo.com/c/product/300603-REG/Canon_9199A001_Extension_Tube_EF_25.html#features

 

[Dino]

I'll test out mine today and see. Honestly though you're better off going with this set -
http://www.bhphotovideo.com/c/product/375102-REG/Kenko_AEXTUBEDGC_Auto_Extension_Tube_Set.html

For just a little bit more you can get that set and have a full set of tubes rather just one tube. There isn't any glass in them and Canon air ain't any different than Kenko air. Any IQ loss will be related to diffraction softening at higher magnifications which will be the same regardless if you're using Canon, Kenko, or el' cheapo ebay tubes with no electrical contacts.

 

[thepenalty]

For just a little bit more you can get that set and have a full set of tubes rather just one tube...

...and if Octoshark is willing to sacrifice the auto focus, he can buy macro rings for less than 10 dollars.

 

[BlueCorn]

...and if Octoshark is willing to sacrifice the auto focus, he can buy macro rings for less than 10 dollars.

You also give up aperture control. Since you'll be wide open your DOF will be just about non-existent.

 

[thepenalty]

Ok, ok, you give up a lot, but consider the price... even if he doesn't like it, he may just throw it out. The sacrifice is minimal.