Comparison of Pentax 55-300mm f/4-5.8 ED SMC DA and Tamron AF 75-300mm f/4-5.6 LD Macro

Attribute	Tamron AF 75-300mm f/4-5.6 LD Macro ×	Pentax 55-300mm f/4-5.8 ED SMC DA ×
Magnification Ratio (x)	0.26	0.28
Filter Size (mm)	62	58
Focus Details	-	Quick-shift Focus System
Closest Focus (m)	1.5	1.4
Lens Construction	13 elements in 9 groups	12 elements in 8 groups, including ED elements
Length (mm)	118.7	111.5
Focal Length (mm)	75.00 - 300.00	55.00 - 300.00
Diagonal Angle of View (degree)	8.00 - 33.00	5.40 - 29.00
Brand	Tamron	Pentax
Image Circle	35mm	APS-C
Name	Tamron AF 75-300mm f/4-5.6 LD Macro	Pentax 55-300mm f/4-5.8 ED SMC DA
Weight (g)	435	440
Type	Telephoto Zoom	Telephoto Zoom
Notes	Available AF Mounts: Canon, Minolta, Nikon, Pentax; Included Accessories: Lens Hood	Included Accessories: Lens Hood
APS Equivalent	1.5x: 112 - 450mm; 1.6x: 120 - 480mm	82.5 - 450mm
Aperture (f)	4.00 - 22.00	4.00 - 32.00
Diaphragm Blades	9	6
Zoom System	Rotary	Rotary
Diameter (mm)	76.6	71