After investing in the Canon 100-400 IS, I'd like to add a 1.4x TC. While the Canon brand gets certainly the better reviews, the price is 4 times a Tamron or Kenco. Should only the Canon be considered no matter what the price?

-- Jeff Nadler (jeff.nadler@ps.ge.com), May 18, 2000

Answers

Get the Kenko Pro TC (apparently also sold by Tamron) The reviews of this TC have been very positive. Comes in 1.4x and 2x flavors.

I shot some images over the weekend with my Nikkor 80-200 f/2.8 zoom with the Kenko 1.4x TC and without and I could not distinguish the images. All were tack sharp, with excellent color and contrast.

There is a rumor afoot, by the way, that Canon's extension tubes are rebadged Kenko tubes. Any truth to it?

-- John Wall (john_wall@ncsu.edu), May 18, 2000.

If you don't have an EOS 3 or 1V, your 100-400 won't AF with the Canon 1.4X TC attached. With first generation EOS bodies, it won't even IS with the Canon TC. ...An argument in favor of the Kenko brand, but if you do have an EOS 3 or 1V, why save pennies when you've spent over $1500 on a fine lens?

There is a rumor afoot, by the way, that Canon's extension tubes are rebadged Kenko tubes. Any truth to it?

The Canon EF 12mm tube may very well be a Kenko knock-off, but the 25mm tube (actually 27.5mm) is nothing like the Kenko. The body of the Canon 25mm tube is identical the body of the EF 1.4X TC, including the 3 extra electrical contacts. The Canon 25mm tube contains electronics which comminicate to the camera body that its attached (for metering corrections).

-- Dave Herzstein (dherzstein@juno.com), May 18, 2000.