Canon EF 200-400mm f/4L IS USM Extender 1.4X Instruction page 24

18. Extenders (Sold Separately)
Lens specifications when using extender EF1.4x II/III or EF2x II/III are as follows.
When the internal extender is set at 1x
Focal length (mm)
Aperture
Diagonal
Vertical
Angle of view
Horizontal
Maximum magnification (x)
When the internal extender is set at 1.4x
Focal length (mm)
Aperture
Diagonal
Angle of view
Vertical
Horizontal
Maximum magnification (x)
Extender EF1.4x II/III
WIDE TELE
280
f/5.6-45 f/5.6-45
8°50' 4°25'
4°55' 2°25'
7°20' 3°40'
0.15 0.22
Extender EF1.4x II/III
WIDE TELE
392
f/8-64 f/8-64
6°20' 3°10'
3°30' 1°45'
5°15' 2°40'
0.21
WIDE
560 400
f/8-64
6°10'
3°30'
5°10'
0.21
WIDE
784 560
f/11-91
4°25'
2°25'
3°40'
0.3 0.3
Extender EF2x II/III
TELE
800
f/8-64
3°05'
1°40'
2°35'
0.31
Extender EF2x II/III
TELE
1120
f/11-91
2°10'
1°15'
1°50'
0.44
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