Last week I rented the Canon 2x extender from the folks at Lumoid with the goal to capture some Bald Eagles on the Skagit River in WA state. I combined the 2x extender with my 70-200 f/2.8 to create a 140-400 f/5.6 lens(more about the switch to f5/.6 in a moment). The eagles were few and far but I still had fun using the lens. Watch the video and review the chart below for compatible lenses.Lenses Compatible with Canon 2x III Extender -Notice that when using this extender your maximum aperture is halved. A f/2.8 becomes f/5.6.
ExtenderEF 2x Compatibility Chart
LensAttachment
FocalLength(mm)
f-stop(f)
Max.Magnification(x)
AF
EF 135mm f/2L USM
270
4 ~ 64
0.38
O
EF 180mm f/3.5L Macro USM
360
6.7*1 ~ 64
2.0
X
EF 200mm f/1.8L USM
400
3.5 ~ 45
0.18
O
EF 200mm f/2L IS USM
400
5.6 ~ 64
0.24
O*4
EF 200mm f/2.8L II USM
400
5.6 ~ 64
0.32
O
EF 300mm f/2.8L IS USM
600
5.6 ~ 64
0.28
O
EF 300mm f/4L IS USM
600
8 ~ 64
0.47
X*4*5
EF 400mm f/2.8L IS USM
800
5.6 ~ 64
0.31
O
EF 400mm f/4L DO IS USM
800
8 ~ 64
0.24
X*4*5
EF 400mm f/5.6L USM
800
11 ~ 64
0.18
X
EF 500mm f/4L IS USM
1,000
8 ~ 90
0.25
X*4*5
EF 600mm f/4L IS USM
1,200
8 ~ 90
0.24
X*4*5
EF 800mm f/5.6L IS USM
1,600
11 ~ 64
0.28
X
EF 1200mm f/5.6L USM
2,400
11 ~ 64
0.18
X
EF 70-200mm f/2.8L USM
140 ~ 400
5.6 ~ 64
0.33
O*2
EF 70-200mm f/2.8L IS USM
140 ~ 400
5.6 ~ 64
0.33
O*2
EF 70-200mm f/2.8L IS II USM
140 ~ 400
5.6 ~ 64
0.33
O*2
EF 70-200mm f/4L USM
140 ~ 400
8 ~ 64
0.45
X*4
EF 70-200mm f/4L IS USM
140 ~ 400
8 ~ 64
0.45
X*4
EF 100-400mm f/4.5-5.6L IS USM
200 ~ 800
9.5 ~ 64
0.41
X*5
(O =possible X =impossible)
*1
Databased on EOS models with exposures displayed in 1/2 stop increments.It varies slightly with the EOS-1v, EOS-1N, EOS-1 and EOS-3.
*2
Ifthe EF 70-200mm f/2.8L USM lens is attached to an EOS camera havingmultiple focusing points and an Extender is attached to the lens,only the center focusing point will be usable for AF.
*3
Theautofocusing range is from 0.8m/2.6ft. to infinity.
*4
With the EOS-1D series, EOS-1v and EOS-3, AF is possible, but with the center focusing point only.
*5
TheImage Stabilizer does not operate with the following cameras: EOS650, 620, 630/600, RT, 700, 750, 850, EOS-1, A2/A2E, 10s, Elan, Rebel/RebelS, Rebel II/Rebel SII.
Verdict - If you have one of the lenses the 2x extender is compatible with and you occasionally need more zoom it is a VERY cost effective way to get there and you can do it with a smaller lens.
Consider renting if you only need occasionally. Buy if you want to double your zoom often without carrying around a much larger lens.
Buy from AmazonCanon 2x Extender Manual