Canon 1.4x - Kenko 1.4x PRO 300 Stacking tip for Canon 300mm f2.8 - Flickr - Dan Pancamo

Photo By Dan Pancamo @pancamo

EXPLORED!? Thanks Everyone!

The Carolina Chickadee, Poecile carolinensis, is a small passerine bird in the tit family Paridae

UPDATE:: 7/31/2012: My Canon 1.4x iii TC arrived today, and this latest iii copy does not work with the Kenko 1.4x Pro 300 on my Canon 300mm f2.8 IS and Canon 7D. The 7D will gain focus for a second, then hunt back and forth apparently looking for a better focus... I'm guessing that the Kenko 1.4x Pro 300 needs to be updated now with the new 1.4x iii model. Oh well... The Canon 1.4x ii model and the Kenko 1.4x Pro 300 is always on my Canon 300 f2.8, and the iii model better work with my new 500mm f4 II which should arrive any day now.

My new Kenko 1.4x toy arrived today. The Canon 2.0x is slow to focus on birds in flight, and Canon 1.4x is a little too short. Thanks to a fellow 300mm birder for the Kinko 1.4x stacking tip that allows you to stack a Canon and a Kenko 1.4x together for 588mm without any loss in focus speed and still close to f4. I didn't do the "tape" trick to get it to register as f4, so metering is -1EV off, so I need to remember to compensate when using this combo.

I can't tell any different in IQ from the 2.x