Using extension tubes

[Dieselrider]

I was just reading in Understanding Exposure about the possibilities with extension tubes and macro. Being the total newb that I am I don't know squat about them. Do they allow you to focus automatically or are they strictly manual? If strictly manual, how will they help with Macro? Are there things to look for when buying such as what to avoid? I am shooting with a Canon XTI if that helps. Any help would be greatly appreciated. Thanks

:camera:

 

[asfixiate]

From what I'm reading extension tubes will work with autofocus. I assume you obviously would have to make sure you get ones that are compatible with your camera/lenses.

This is from an article I just read.

Extension tubes are designed to enable a lens to focus closer than its normal set minimum focusing distance. Getting closer has the effect of magnifying your subject (making it appear larger in the viewfinder and in your pictures). They are exceptionally useful for macro photography, enabling you to convert almost any lens into a macro lens at a fraction of the cost while maintaining its original optical quality.

 

[Big Mike]

Have a look at the Kenko Extension tube set.
http://www.bhphotovideo.com/c/product/375102-REG/Kenko_AEXTUBEDGC_Auto_Extension_Tube_Set.html

And yes, as long as you get compatible tubes, they should allow you to use auto focus. That being said, it is sometimes easier to actually use manual focus for macro...and sometimes it's easier to adjust the focus by adjusting the position of the camera, rather than actually focusing the lens.

 

[asfixiate]

That's actually where I got what I said from...lol.

 

[250Gimp]

Watch out for some cheaper extension tubes as they don't allow any contact betwen camera and lense, so they are strictly manual.

I use my kenko tubes on manual mostly, and move the camera back and forth, on its tripod, to get the focus I want.

You loose quite a bit of light while using the tubes, so some lenses won't focus on automatically with a full 68mm of tubes.

Cheers