Extension tubes

[burnxkr]

I am looking to but some extension tubes to use with my 1D MKIII and 100 2.8 macro.

Is there any point in paying the extra for the Canon brand as opposed to something like the Kenko set?

Does common sense suggest that the longer the extension the closer in I can focus?

Any other alternatives or advice would be appreciated.

[John_B]

burnxkr,
The Kenko set is great! :)
Why pay more for less extension? ???
Is Canon air better then Kenko? ???

The longer the extension the more magnification ex. with a full set of Kenko 68mm with a 100mm macro you can get 2:1 macro (2 x lifesize). However too long and you won't be able to focus on an external subject ;)

In Macro Variations I show the magnifications possible with my 100mm and Kenko tubes <-- click to see (http://photography-on-the.net/forum/showthread.php?t=578274)

[ShutterBugL]

Third party extension tubes are fine, since there are no glass elements inside the tubes. However, be sure to buy 3rd party tubes that are robustly built. The last thing you want is to have your 100mm coming loose. I have used Triplus ext. tubes for a few years and (thankfully) no problems so far.

[red_fan]

Basically echoing the above, the build quality may be better, but the image quality will be exactly the same because there is nothing but air in them.

Stephen

[pturton]

There may be nothing but air in the lens area but you still want quality contacts so that your camera can reliably read or set your aperture. Also, as mentioned, a robust build is necessary to support your heaviest lens without failure. Just imagine your 70-200 f/2.8 L IS falling unto the concrete because the screws holding the mounting ring let go.

I have and use Canon extension tubes but I've never heard anything but praise for the Kenko 3 extension set.

[burnxkr]

Kenko it is then.

[Namerifrats]

Finishing up my decisions on things to order in a few days for my Macro rig. The Kenko set of tubes is on the list!