I have just ordered a Canon EF 70-200mm F/4L IS USM lens from Adorama (Amazon stock availability was on and off, and Adorama also had free shipping like Amazon), and am looking at the possibility of adding a 1.4X Tele Converter to my kit. On the 1.6X FOV crop EOS 400D body I am using, the lens behaves as a 112 - 320 mm F/4 lens, combined with a 1.4X TC, it will become a 157 - 448 mm F/5.6 lens. The intended usage is for candid and wildlife photography.
Note that the 1.4X reduces the maximum aperture by 1 stop whereas the 2X TC reduces it by 2 stops. So the F/4 lens becomes a F/5.6 lens with the 1.4X TC attached. Note also that Canon bodies (other than the professional bodies) cannot autofocus if the max aperture of the lens is smaller than F/5.6. So I will retain AF with 1.4 TC, but not with a 2X TC as that reduces the max aperture of my F/4 lens to F/8.
I researched on the net for the following options:
- Canon EF 1.4X II
- Tamron 1.4X AF
- Tamron SP AF 1.4X Pro
- Kenko Teleplus PRO 300 DG AF 1.4X
- Weather resistant
- Limited to certain lenses (L series mostly) due to construction
- Reports correct minimum aperture to camera
- Lowers AF speed to accommodate the TC
Since the 70-200 F4 IS is the only "L" lens I own as of now, the Canon 1.4X would be a bit of overkill for me at this price.
Tamron 1.4X AF
- Cheapest of the lot
- Does not report aperture to body correctly
- Black, does not go well with white of L series lens (well that matters a bit!)
- Optimized for F/2.8
- Claimed to be identical to Kenko PRO
- White (matches L series)
- Good reviews
- Claimed to be identical to Tamron SP 1.4X
- Cheaper on eBay
After reading all the reviews and comments online, it looks like the Kenko PRO & Tamron SP are good bets over the Canon which is $100 more. I am inclined to pick up the Tamron because 1) I have used Tamron lenses before and like them and 2) it is white and will match my new 70-200 mm f/4L IS and 3) it is said to be optically identical to Kenko 1.4X PRO which has good reviews and 4) it will be useful if I upgrade or buy any F/2.8 lenses in future.
- Overview of TCs by Sean
- From Bob Atkins, an overview of TCs
- Comparison between Canon 1.4X and Tamron 1.4X on photo.net by Bob Atkins
- A FAQ on teleconverters at Photography-on-the-Net
- Tamron/Kenko compared aginst Nikon in NikonLinks