Pentax smc Pentax-FA 43mm f/1.9 Limited Specs & DoF

43 mm

Focal length

f/1.9

Maximum aperture

53°

Diagonal angle of view (Full frame)

Full frame

Designed for

Specifications#

Brand: Pentax
Model: smc Pentax-FA 43mm f/1.9 Limited
Lens type: Standard prime
Focal length: 43 mm
Maximum aperture: f/1.9
Image circle: Full frame (36×24 mm)
Mount(s): Pentax K
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 format	At 43 mm	Equiv. aperture (DoF)
Full frame	43 mm · 53°	f/1.9
APS-C	64 mm · 36°	f/2.8
APS-C (Canon)	69 mm · 35°	f/3.0
Micro Four Thirds	86 mm · 28°	f/3.8

Depth of field & background blur#

Computed on its native Full frame format (CoC 30 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: 40 mm f/2 on full frame.

Focal	Aperture	at 1 m	at 2 m	at 5 m	at 10 m	Hyperfocal	Blur @2 m
43 mm	f/1.9	5.9 cm	24.2 cm	1.56 m	6.78 m	32.5 m	1.4%
43 mm	f/4	12.5 cm	51.6 cm	3.59 m	22.2 m	15.5 m	0.7%
43 mm	f/8	25.2 cm	1.09 m	11.0 m	∞	7.75 m	0.3%

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).

Body	Min. handheld shutter (longest focal)	500 rule at 43 mm	NPF at 43 mm, f/1.9
Full frame	1/40 s	12 s	6 s
APS-C	1/60 s	8 s	4 s
APS-C (Canon)	1/60 s	7 s	4 s
Micro Four Thirds	1/80 s	6 s	4 s

Compatible cameras#

Bodies in our database with a native Pentax K mount.

Adapt it to other systems#

Sony E-mount Canon RF Nikon Z Fujifilm X-mount Micro Four Thirds L-Mount Canon EF-M Fujifilm G-mount Hasselblad XCD Nikon 1 (CX)Pentax Q Samsung NX Canon EF Nikon F

Similar lenses#

Pentax smc Pentax-DA 40mm f/2.8 Limited f/2.8
Pentax smc Pentax-DA 40mm f/2.8 XS f/2.8
Pentax smc Pentax-A 50mm f/1.4 f/1.4
Pentax smc Pentax-A 50mm f/1.7 f/1.7
Pentax smc Pentax-FA 50mm f/1.4 f/1.4
Pentax smc Pentax-FA 50mm f/1.7 f/1.7
Pentax smc Pentax-M 50mm f/1.4 f/1.4
Pentax smc Pentax-M 50mm f/1.7 f/1.7
Pentax smc Pentax-M 50mm f/2 f/2
Sigma 50mm f/1.4 EX DG HSM f/1.4
Pentax smc Pentax-DA 35mm f/2.4 AL f/2.4
Pentax smc Pentax-M 35mm 1:2 f/2

Frequently asked questions#

Is the Pentax smc Pentax-FA 43mm f/1.9 Limited full frame?

Yes — it covers the full 36 × 24 mm frame.

What is the Pentax smc Pentax-FA 43mm f/1.9 Limited equivalent to on APS-C?

On a 1.5× APS-C body it frames like 64 mm, and like 69 mm on Canon APS-C.

What is the Pentax smc Pentax-FA 43mm f/1.9 Limited good for?

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

Sources & licences#

Lensfun lens database — CC BY-SA 3.0