Standard prime · Four Thirds

Panasonic G 20mm f/1.7 II Asph.

The Panasonic G 20mm f/1.7 II Asph. is a four thirds prime lens (20 mm, f/1.7) for Micro Four Thirds. It belongs to the standard prime class — ideal for street, documentary, everyday and low-light shooting.

20 mmf/1.7Micro Four Thirds
20 mm
Focal length
f/1.7
Maximum aperture
57°
Diagonal angle of view (Four Thirds)
Four Thirds
Designed for

Specifications#

Model
G 20mm f/1.7 II Asph.
Lens type
Standard prime
Focal length
20 mm
Maximum aperture
f/1.7
Image circle
Four Thirds (17.3×13 mm)
Projection
Rectilinear
Lensfun correction profile
Yes — distortion/vignetting/TCA

Equivalent focal length on different cameras#

Field of view and depth-of-field equivalence when this lens is used on bodies with different sensor sizes (natively or via an adapter).

Camera formatAt 20 mmEquiv. aperture (DoF)
Micro Four Thirds40 mm · 57°f/3.4

Depth of field & background blur#

Computed on its native Four Thirds format (CoC 15 µm). “Blur @2 m” is the size of an out-of-focus point at infinity, as a percentage of frame width, with the subject at 2 m — a simple bokeh index. Full table: 20 mm f/1.8 on four thirds.

FocalApertureat 1 mat 2 mat 5 mat 10 mHyperfocalBlur @2 m
20 mmf/1.712.5 cm51.3 cm3.53 m21.4 m15.7 m0.7%
20 mmf/430.1 cm1.30 m16.9 m∞6.68 m0.3%
20 mmf/864.4 cm3.67 m∞∞3.35 m0.1%

Handheld & night-sky limits#

NPF assumes typical 20–24 MP sensors (≈6 µm pixels on full frame, ≈3.9 µm on APS-C, ≈3.3 µm on Micro Four Thirds).

BodyMin. handheld shutter (longest focal)500 rule at 20 mmNPF at 20 mm, f/1.7
Micro Four Thirds1/40 s12 s8 s

Adapt it to other systems#

Frequently asked questions#

Is the Panasonic G 20mm f/1.7 II Asph. full frame?

No — it is designed for Four Thirds sensors.

What is the Panasonic G 20mm f/1.7 II Asph. equivalent to on APS-C?

Its focal length is already the real value for Four Thirds: 20 mm frames like 40 mm on full frame.

What is the Panasonic G 20mm f/1.7 II Asph. good for?

As a standard prime it suits street, documentary, everyday and low-light shooting.

Sources & licences#

Last updated October 03, 2026 · How we calculate · Sources