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1.4x extender on 135/2.0 | |
It works really well. I recently compared USAF 1951 test chart resolution results for the 135/2L with Canon 1.4x Extender and Tamron SP 1.4x teleconverter, and with SMC Pentax 200/2.5, Canon 70-200/2.8L IS, Canon 100-300/5.6L, and Tokina AT-X 24-200/3.5-5.6, with all of the zooms at 200mm. The tests were done with a 20D at ISO 100 on a tripod with MLU. I often use the 135/2L with 1.4x on my 5D, but I haven't tested it. Here's the calculated resolution in lines per mm (lpmm), in order from best to worst for a few different conditions. Anything above 50 lpmm is pretty darned good. The 5D sensor resolution is about 60 lpmm, 20D is 78 lpmm - same as the 1DsIII.
centre resolution, wide open (135/2 at f/2, 100-300/5.6L at f/5.6, etc.)
68 lpmm EF 100-300/5.6 L
64 lpmm EF 135/2 L USM + EF 1.4x
57 lpmm EF 135/2 L USM + SP 1.4x
55 lpmm EF 70-200/2.8 L IS USM
48 lpmm AT-X 24-200/3.5-5.6
48 lpmm SMC Pentax 200/2.5
centre resolution at f/8
78 lpmm EF 70-200/2.8 L IS USM
68 lpmm EF 100-300/5.6 L
64 lpmm EF 135/2 L USM + EF 1.4x
64 lpmm EF 135/2 L USM + SP 1.4x
61 lpmm SMC Pentax 200/2.5
54 lpmm AT-X 24-200/3.5-5.6
corner resolution, wide open (135/2 at f/2, 100-300/5.6L at f/5.6, etc.)
61 lpmm EF 100-300/5.6 L
57 lpmm EF 135/2 L USM + EF 1.4x
48 lpmm SMC Pentax 200/2.5
44 lpmm EF 70-200/2.8 L IS USM
40 lpmm EF 135/2 L USM + SP 1.4x
34 lpmm AT-X 24-200/3.5-5.6
corner resolution, at f/8
68 lpmm EF 100-300/5.6 L
64 lpmm EF 135/2 L USM + EF 1.4x
64 lpmm EF 135/2 L USM + SP 1.4x
61 lpmm SMC Pentax 200/2.5
55 lpmm EF 70-200/2.8 L IS USM
43 lpmm AT-X 24-200/3.5-5.6
The EF 100-300/5.6L is pretty good, eh?
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