Ricoh Pentax K-3 II Specs, Sensor Size & Crop Factor

Q: What is the crop factor of the Ricoh Pentax K-3 II?

The Ricoh Pentax K-3 II has a crop factor of 1.53× relative to 35 mm full frame (diagonal 28.2 mm vs 43.3 mm).

1.53×

Crop factor

23.5×15.6 mm

Sensor size

367 mm²

Area · 42% of full frame

24 MP

Resolution

3.91 µm

Pixel pitch

f/5.8

Diffraction-limited aperture

2015

Release year

Specifications#

Brand: Ricoh
Model: Pentax K-3 II
Also known as: K-3 II
Camera type: DSLR
Released: 2015-01-01
Lens mount: Pentax K
Sensor size: 23.5 × 15.6 mm (APS-C)
Crop factor: 1.53×
Resolution: 24 MP (6,016 × 4,000 px)
ISO range: 100 – 51,200
Fastest shutter: 1/8,000 s
Continuous shooting: 8.3 fps
Max video resolution: 1080p
Weight: 700 g (24.7 oz)
Sensor type: CMOS
Viewfinder: Eye-level pentaprism
AF points / area: 27 focus points (25 cross-type)
Metering: TTL open aperture metering using 86K pixel RGB sensor
Exposure modes: Green (Auto), Manual (M), Aperture Priority (Av), Shutter Priority (Tv), Shutter and Aperture Priority (TAv), Sensitivity Priority (Sv), Flexible Program (P), Bulb (B), Flash Sync (X), 3 User Modes
Shutter: Electronically controlled vertical-run focal plane shutter (Electronic shutter when using Pixel Shift Resolution)
Flash: External only: 1/180 X-sync speed, hot shoe for P-TTL flash units with high-speed sync support, X-sync socket
Battery: D-Li90 (1860 mAh 7.2 V, 13.39 Wh)
Dimensions: 131 x 100 x 77mm (5.16 x 3.94 x 3.03 inches)
Lens: Interchangeable lens
Predecessor: Pentax K-3
Successor: Pentax K-3 Mark III
Launch price: $999
Production: 2015-2018
Drive: up to 8.3 fps for 60 JPG or 23 RAW images
Video: 1920x1080 (60i/50i/30p/25p/24p）; 1280x720 (60p/50p/30p/25p/24p)

Specifications merged from Wikipedia, Wikidata, Lensfun and openMVG. Spot an error? Tell us.

Sensor size compared#

The Ricoh Pentax K-3 II sensor (highlighted) drawn to scale against common formats. Its area is 42% of a full-frame sensor, which collects about 1.2 stops less total light at the same exposure.

Focal length equivalents & field of view#

Multiply any focal length by 1.53 to get the full-frame field of view. Angles are for a rectilinear lens focused at infinity.

Lens on this camera	Full-frame equivalent	Horizontal	Vertical	Diagonal
8 mm	12 mm	111.5°	88.5°	120.9°
10 mm	15 mm	99.2°	75.9°	109.3°
12 mm	18 mm	88.8°	66.0°	99.2°
14 mm	21 mm	80.0°	58.2°	90.4°
16 mm	25 mm	72.6°	52.0°	82.8°
18 mm	28 mm	66.3°	46.9°	76.2°
20 mm	31 mm	60.9°	42.6°	70.4°
24 mm	37 mm	52.2°	36.0°	60.9°
28 mm	43 mm	45.5°	31.1°	53.5°
35 mm	54 mm	37.1°	25.1°	43.9°
40 mm	61 mm	32.7°	22.1°	38.8°
50 mm	77 mm	26.4°	17.7°	31.5°
56 mm	86 mm	23.7°	15.9°	28.3°
70 mm	107 mm	19.1°	12.7°	22.8°
85 mm	130 mm	15.7°	10.5°	18.8°
100 mm	153 mm	13.4°	8.9°	16.1°
135 mm	207 mm	9.9°	6.6°	11.9°
200 mm	307 mm	6.7°	4.5°	8.1°
300 mm	460 mm	4.5°	3.0°	5.4°
400 mm	614 mm	3.4°	2.2°	4.0°
600 mm	920 mm	2.2°	1.5°	2.7°
800 mm	1227 mm	1.7°	1.1°	2.0°

Depth of field table#

Total depth of field at each subject distance, using a circle of confusion of 19.6 µm (the 0.030 mm full-frame standard scaled by the crop factor). Detailed tables: 24 mm f/1.8, 24 mm f/2.8, 35 mm f/1.8, 35 mm f/2.8, 50 mm f/1.8, 50 mm f/2.8.

Focal	Aperture	50.0 cm	1.00 m	2.00 m	3.00 m	5.00 m	10.0 m	Hyperfocal
14 mm	f/1.8	8.8 cm	36.6 cm	1.63 m	4.52 m	45.2 m	∞	5.58 m
14 mm	f/2.8	13.8 cm	59.6 cm	3.21 m	16.5 m	∞	∞	3.59 m
14 mm	f/4	20.2 cm	93.1 cm	8.53 m	∞	∞	∞	2.52 m
14 mm	f/8	45.7 cm	4.14 m	∞	∞	∞	∞	1.27 m
28 mm	f/1.8	2.1 cm	8.7 cm	35.7 cm	81.5 cm	2.35 m	11.2 m	22.3 m
28 mm	f/2.8	3.3 cm	13.6 cm	56.2 cm	1.30 m	3.95 m	27.1 m	14.3 m
28 mm	f/4	4.7 cm	19.6 cm	81.9 cm	1.95 m	6.58 m	2.0 km	10.0 m
28 mm	f/8	9.5 cm	40.3 cm	1.86 m	5.49 m	643 m	∞	5.04 m
48 mm	f/1.8	0.7 cm	2.9 cm	11.9 cm	27.1 cm	76.1 cm	3.11 m	65.5 m
48 mm	f/2.8	1.1 cm	4.5 cm	18.6 cm	42.3 cm	1.19 m	5.01 m	42.1 m
48 mm	f/4	1.5 cm	6.5 cm	26.6 cm	60.8 cm	1.73 m	7.63 m	29.5 m
48 mm	f/8	3.1 cm	13.0 cm	54.0 cm	1.25 m	3.79 m	24.9 m	14.8 m
78 mm	f/1.8	0.2 cm	1.1 cm	4.4 cm	10.1 cm	28.5 cm	1.15 m	173 m
78 mm	f/2.8	0.4 cm	1.7 cm	6.9 cm	15.8 cm	44.4 cm	1.80 m	111 m
78 mm	f/4	0.5 cm	2.4 cm	9.9 cm	22.6 cm	63.5 cm	2.59 m	77.8 m
78 mm	f/8	1.1 cm	4.7 cm	19.8 cm	45.3 cm	1.29 m	5.46 m	39.0 m

Equivalent aperture#

Exposure is identical at the same f-number on any format; equivalence only describes depth of field and total light.

Aperture on this camera	Full-frame equivalent (depth of field)	Hyperfocal at 28 mm
f/1.2	f/1.8	33.4 m
f/1.4	f/2.1	28.7 m
f/1.8	f/2.8	22.3 m
f/2	f/3.1	20.1 m
f/2.8	f/4.3	14.3 m
f/4	f/6.1	10.0 m
f/5.6	f/8.6	7.19 m
f/8	f/12.3	5.04 m

Diffraction & pixel pitch#

With 3.91 µm pixels, diffraction starts to soften pixel-level detail around f/5.8. For maximum sharpness keep landscapes between f/3.2 and f/6; stopping down further trades detail for depth of field.

Aperture	Airy disk diameter	Spread over	At 100% view
f/2.8	3.8 µm	1.0 px	sharp
f/4	5.4 µm	1.4 px	sharp
f/5.6	7.5 µm	1.9 px	sharp
f/8	10.7 µm	2.7 px	slight softening
f/11	14.8 µm	3.8 px	visibly soft
f/16	21.5 µm	5.5 px	visibly soft
f/22	29.5 µm	7.6 px	visibly soft

Maximum print sizes#

At 24 MP the Ricoh Pentax K-3 II produces 6,016 × 4,000 pixel images. See the 24 megapixel guide or the print size calculator.

Resolution	Typical use	Inches	Centimetres
300 DPI	Photo-lab quality	20.1 × 13.3 in	51 × 34 cm
240 DPI	Fine-art inkjet	25.1 × 16.7 in	64 × 42 cm
200 DPI	Wall print	30.1 × 20.0 in	76 × 51 cm
150 DPI	Poster, viewed from 1 m+	40.1 × 26.7 in	102 × 68 cm

Night-sky exposure limits#

Longest exposure before stars trail. The NPF rule accounts for pixel pitch and is stricter than the classic 500 rule — use it for pin-sharp stars on high-resolution sensors.

Focal length	500 rule	NPF f/1.8	NPF f/2.8	NPF f/4
9 mm (14 mm eq.)	36.2 s	20.0 s	23.9 s	28.6 s
13 mm (20 mm eq.)	25.1 s	13.9 s	16.6 s	19.8 s
16 mm (25 mm eq.)	20.4 s	11.3 s	13.4 s	16.1 s
23 mm (35 mm eq.)	14.2 s	7.8 s	9.4 s	11.2 s
33 mm (51 mm eq.)	9.9 s	5.5 s	6.5 s	7.8 s

Open the NPF / 500 rule calculator →

Handheld shutter speed guide#

The reciprocal rule uses the equivalent focal length. High-resolution sensors may need one stop faster than this for pixel-sharp results.

Focal length	No stabilisation (1/equiv. focal)	With 3-stop IS	With 5-stop IBIS
16 mm	1/25 s	0.3 s	1.3 s
33 mm	1/50 s	1/6 s	0.6 s
65 mm	1/100 s	1/13 s	0.3 s
130 mm	1/200 s	1/25 s	1/6 s

Lenses for the Ricoh Pentax K-3 II#

Native Pentax K lenses in our database (170 total). Also adaptable: T-mount (T2), M42 screw mount, Deckel (DKL), Tamron Adaptall, M39 / LTM (Leica thread).

Samyang 8mm f/3.5 Fish-Eye CS 8 mm
Samyang 10mm f/2.8 ED AS NCS CS 10 mm
Laowa 12mm f/2.8 Zero-D 12 mm
Samyang 14mm f/2.8 AE ED AS IF UMC 14 mm
Laowa 15mm F/4 Wide Angle Macro 15 mm
Samyang 16mm f/2.0 ED AS UMC CS 16 mm
Samyang 20mm f/1.8 ED AS UMC 20 mm
Samyang 24mm f/1.4 ED AS IF UMC 24 mm
Samyang T-S 24mm f/3.5 ED AS UMC 24 mm
Laowa 60mm f/2.8 2X Ultra-Macro 60 mm
Samyang 85mm f/1.4 IF UMC Aspherical 85 mm
Samyang 135mm f/2 ED UMC 135 mm
Sigma 4.5mm f/2.8 EX DC HSM circular fisheye 4.5 mm
Sigma 8-16mm f/4.5-5.6 DC HSM 8–16 mm
Pentax smc Pentax-DA Fish-Eye 10-17mm f/3.5-4.5 ED IF 10–17 mm
Sigma 10-20mm f/3.5 EX DC HSM 10–20 mm
Sigma 10-20mm f/4-5.6 EX DC 10–20 mm
Sigma 10mm f/2.8 EX DC Fisheye HSM 10 mm
Tamron SP AF 10-24mm f/3.5-4.5 Di II LD Aspherical (IF) 10–24 mm
Pentax HD Pentax-DA* 11-18mm f/2.8 ED DC AW 11–18 mm
Tamron SP AF 11-18mm f/4.5-5.6 Di-II LD Aspherical (IF) 11–18 mm
Pentax smc Pentax-DA 12-24mm f/4 ED AL IF 12–24 mm
Sigma 12-24mm F4.5-5.6 II DG HSM 12–24 mm
Sigma 12-24mm f/4.5-5.6 EX DG Aspherical HSM 12–24 mm
Pentax smc PENTAX-DA 14mm F2.8 ED[IF] 14 mm
Sigma 14mm f/2.8 EX 14 mm
Sigma 14mm f/2.8 EX Aspherical HSM 14 mm
Sigma 14mm f/3.5 EX 14 mm
Pentax HD Pentax-D FA 15-30mm f/2.8 ED SDM WR 15–30 mm
Pentax smc Pentax-DA 15mm f/4 ED AL Limited 15 mm
Sigma 15-30mm f/3.5-4.5 EX DG Aspherical 15–30 mm
Sigma 15mm f/2.8 EX DG Diagonal Fisheye 15 mm
Pentax HD Pentax DA* 16-50mm f/2.8 ED PLM AW 16–50 mm
Pentax HD Pentax-DA 16-85mm f/3.5-5.6 ED DC WR 16–85 mm
Pentax smc Pentax-DA 16-45mm f/4 ED AL 16–45 mm
Pentax smc Pentax-DA* 16-50mm f/2.8 ED AL IF SDM 16–50 mm

Similar cameras#

Other APS-C cameras from around the same time.

Frequently asked questions#

What is the crop factor of the Ricoh Pentax K-3 II?

The Ricoh Pentax K-3 II has a crop factor of 1.53× relative to 35 mm full frame (diagonal 28.2 mm vs 43.3 mm).

What size is the Ricoh Pentax K-3 II sensor?

23.5 × 15.6 mm (APS-C), an area of 367 mm² — 42% of full frame.

Is the Ricoh Pentax K-3 II full frame?

No — its sensor is APS-C, which is 2.4× smaller in area than full frame.

How many megapixels does the Ricoh Pentax K-3 II have?

24 megapixels (6,016 × 4,000 pixels), enough for a 20 × 13 inch print at 300 DPI.

What lens mount does the Ricoh Pentax K-3 II use?

The Ricoh Pentax K-3 II uses the Pentax K (flange distance 45.46 mm).

How long can I expose the night sky with the Ricoh Pentax K-3 II?

With a 13 mm lens (20 mm equivalent) the 500 rule gives 25 s and the stricter NPF rule at f/2.8 gives 17 s.

Sources & licences#

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