40D + 100mm + extension tubes

[TTA]

Hi!

I met a marine biologist who had a sweet setup with a 40D + 100mm + extension tubes for taking super macro shots. I'm trying to replicate. Got the 40D and 100mm, but am trying to buy the extension tubes and figure out which port he had (we both have the Sea&Sea housing). It required manual focus. Can anyone help?

Thanks!

 

[bvanant]

The Kenko extension tubes come in 12, 20 and 36 mm versions. You can stack them to make 12, 20, 32, 36, 48 etc. Mine autofocus though, but you do lose infinity focus. Great for teeny stuff. If you do that you might want to add a teleconverter to get you some more working distance.
Bill

 

[Ryan]

After experimenting with extension tubes, diopters, and teleconverters extensively I'm convinced that teleconverters are the best super macro accessory for lenses like the 100. 1.4x will get you 1.4:1, and 2x will get you 2:1 (13mm frame width!). 2x does degrade sharpness, but in my opinion this is offset by the added magnification.

 

[bvanant]

Ryan:
The only reason to use the extension tubes is for EF-s lenses where I would use both the short extension tube and the teleadapter unless you know of a tele for EF-s lenses