Comparison of Canon RF 70-200mm f/4L IS USM and Pentax SMC P-FA 135mm f/2.8 IF

Attribute	Canon RF 70-200mm f/4L IS USM ×	Pentax SMC P-FA 135mm f/2.8 IF ×
Magnification Ratio (x)	0.28	-
Focus Details	Internal; Dual Nano Ultrasonic Motor (USM) with full-time manual focus; Focus limit switch	Internal
Closest Focus (m)	0.6	0.7
Diaphragm Blades	9	-
Length (mm)	120	79
Aperture (f)	4.00 - 32.00	2.80 - 22.00
Diameter (mm)	83	64
Brand	Canon	Pentax
Image Circle	35mm	35mm
Weight (g)	695	374
Name	Canon RF 70-200mm f/4L IS USM	Pentax SMC P-FA 135mm f/2.8 IF
Type	Telephoto Zoom	Telephoto Prime
Lens Construction	16 lens elements in 11 groups, including four UD lenses; Air-Sphere Coating; Fluorine coating	8 elements in 7 groups
Diagonal Angle of View (degree)	12.00 - 34.00	18.00
Filter Size (mm)	77	52
Focal Length (mm)	70.00 - 200.00	135.00
Notes	Optical Image stabilization with up to 5 stops of correction at 200mm; Up to 7.5 stops of combined IS with EOS R5/R6 bodies	-
APS Equivalent	112 - 320mm	202.5mm
Diaphragm Blades Type	rounded	-
Zoom System	Rotary	-