Compare lenses

Pentax smc DA 17-70mm f/4 AL [IF] SDM vs Pentax smc DA 18-55mm f/3.5-5.6 AL WR

The Pentax smc DA 17-70mm f/4 AL [IF] SDM and the Pentax smc DA 18-55mm f/3.5-5.6 AL WR side by side, computed from this guide's catalogue.

Which to pick

Pick the Pentax smc DA 17-70mm f/4 AL [IF] SDM if you want more reach (to 105mm equivalent). Pick the Pentax smc DA 18-55mm f/3.5-5.6 AL WR if you want a brighter f/3.5 (0.4 stops more light), for dim light and softer backgrounds.

Still torn? Ask the guide about the Pentax smc DA 17-70mm f/4 AL [IF] SDM and the Pentax smc DA 18-55mm f/3.5-5.6 AL WR

Specs side by side

Rows that differ are in full colour; the better value is marked where one is better by any measure.
Spec	Pentax smc DA 17-70mm f/4 AL [IF] SDM	Pentax smc DA 18-55mm f/3.5-5.6 AL WR
Maker	Pentax	Pentax
Focal length	17-70mm (zoom)	18-55mm (zoom)
Full-frame equivalent	26-105mm on APS-C	27-82mm on APS-C
Maximum aperture	f/4	f/3.5-5.6brighter
Made for	APS-C	APS-C
Mounts	Pentax K	Pentax K
Stabilised	no	no
Autofocus	yes	yes
Zoom range	4.1×more range	3.1×
Weight	not listed	235 g
Cameras it fits	20 in this guide	20 in this guide

Focal range, in full-frame terms

Pentax smc DA 17-70mm f/4 AL [IF] SDM: 17-70mm on APS-C, like 26-105mm.

Pentax smc DA 18-55mm f/3.5-5.6 AL WR: 18-55mm on APS-C, like 27-82mm.

Aperture

Pentax smc DA 17-70mm f/4 AL [IF] SDM: f/4 wide open.

Pentax smc DA 18-55mm f/3.5-5.6 AL WR: f/3.5 wide open.

Each opening drawn to scale against f/1.4: a smaller f-number lets in more light and blurs the background more.

Field of view

How wide each sees, at each end, on the sensor it was made for.

Cameras they fit

20 cameras in this guide take both, so either works on the same body.