Lenses tested:
+ Pentax A 200mm f4, by itself and with Sigma 1.4x teleconverter
+ Pentax A* 300mm f4
+ Sigma EX 70-200mm f2.8, by itself and with Sigma EX 1.4x and EX 2x teleconverters
+ Sigma 135-400 f4.5-5.6
+ Tamron 70-300mm f4-5.6 Apo
+ Tamron SP 500mm f8 cat
Camera: Pentax *ist-D (ISO 200)
Target: A south-facing garage about 80 yards away
Postprocessing; Autolevels and crops of 300x300 pixels from center and corner of images
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