Medium-format digital

Phase One IQ180

The Phase One IQ180 is a medium-format digital with a Medium format 53.4 × 40 mm sensor measuring 55.9 × 37.3 mm. Its crop factor is 0.64× — wider than full frame, so a 50 mm lens frames like 32 mm. Every number below is calculated for this exact sensor.

Medium format 53.4 × 40 mm0.64× cropMamiya 645
0.64×
Crop factor
55.9×37.3 mm
Sensor size
2083 mm²
Area · 241% of full frame

Specifications#

Model
IQ180
Lens mount
Mamiya 645
Sensor size
55.9 × 37.3 mm (Medium format 53.4 × 40 mm)
Crop factor
0.64×

Specifications merged from Lensfun. Spot an error? Tell us.

Sensor size compared#

Phase One IQ180Medium format 44 × 33 mmFull frame (35 mm)APS-C
The Phase One IQ180 sensor (highlighted) drawn to scale against common formats. Its area is 241% of a full-frame sensor.

Focal length equivalents & field of view#

Multiply any focal length by 0.64 to get the full-frame field of view. Angles are for a rectilinear lens focused at infinity.

Lens on this cameraFull-frame equivalentHorizontalVerticalDiagonal
21 mm14 mm106.2°83.2°116.0°
23 mm15 mm101.1°78.0°111.2°
28 mm18 mm89.9°67.3°100.4°
32 mm21 mm82.3°60.4°92.8°
35 mm23 mm77.2°56.1°87.6°
45 mm29 mm63.7°45.0°73.5°
55 mm35 mm53.9°37.4°62.8°
63 mm41 mm47.8°33.0°56.1°
80 mm52 mm38.5°26.2°45.6°
90 mm58 mm34.5°23.4°40.9°
110 mm71 mm28.5°19.2°34.0°
120 mm77 mm26.2°17.7°31.3°
150 mm97 mm21.1°14.2°25.2°
180 mm116 mm17.7°11.8°21.1°
250 mm161 mm12.8°8.5°15.3°
350 mm225 mm9.1°6.1°11.0°

Depth of field table#

Total depth of field at each subject distance, using a circle of confusion of 46.6 µm (the 0.030 mm full-frame standard scaled by the crop factor).

FocalAperture50.0 cm1.00 m2.00 m3.00 m5.00 m10.0 mHyperfocal
34 mmf/1.83.4 cm14.1 cm58.2 cm1.35 m4.14 m30.3 m13.8 m
34 mmf/2.85.3 cm22.1 cm93.3 cm2.26 m8.17 m∞8.90 m
34 mmf/47.6 cm31.9 cm1.41 m3.72 m22.3 m∞6.24 m
34 mmf/815.4 cm69.0 cm4.24 m66.9 m∞∞3.14 m
67 mmf/1.80.8 cm3.5 cm14.5 cm33.0 cm92.9 cm3.84 m53.6 m
67 mmf/2.81.3 cm5.4 cm22.5 cm51.5 cm1.46 m6.30 m34.5 m
67 mmf/41.8 cm7.8 cm32.3 cm74.1 cm2.14 m9.94 m24.2 m
67 mmf/83.6 cm15.6 cm65.9 cm1.55 m4.92 m51.5 m12.1 m
114 mmf/1.80.2 cm1.1 cm4.9 cm11.2 cm31.6 cm1.28 m155 m
114 mmf/2.80.4 cm1.8 cm7.6 cm17.4 cm49.2 cm2.00 m99.7 m
114 mmf/40.6 cm2.5 cm10.8 cm24.9 cm70.4 cm2.89 m69.9 m
114 mmf/81.1 cm5.1 cm21.7 cm50.0 cm1.43 m6.17 m35.0 m
188 mmf/1.80.1 cm0.4 cm1.7 cm4.0 cm11.4 cm46.6 cm422 m
188 mmf/2.80.1 cm0.6 cm2.7 cm6.2 cm17.8 cm72.5 cm271 m
188 mmf/40.2 cm0.9 cm3.8 cm8.9 cm25.4 cm1.04 m190 m
188 mmf/80.3 cm1.7 cm7.6 cm17.8 cm50.9 cm2.09 m95.0 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 cameraFull-frame equivalent (depth of field)Hyperfocal at 67 mm
f/1.2f/0.880.4 m
f/1.4f/0.968.9 m
f/1.8f/1.253.6 m
f/2f/1.348.2 m
f/2.8f/1.834.5 m
f/4f/2.624.2 m
f/5.6f/3.617.3 m
f/8f/5.212.1 m

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. (NPF needs a known resolution and is omitted here.)

Focal length500 rule
22 mm (14 mm eq.)35.3 s
31 mm (20 mm eq.)25.0 s
37 mm (24 mm eq.)21.0 s
54 mm (35 mm eq.)14.4 s
78 mm (50 mm eq.)10.0 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 lengthNo stabilisation (1/equiv. focal)With 3-stop ISWith 5-stop IBIS
37 mm1/25 s0.3 s1.3 s
78 mm1/50 s1/6 s0.6 s
155 mm1/100 s1/13 s0.3 s
311 mm1/200 s1/25 s1/6 s

Frequently asked questions#

What is the crop factor of the Phase One IQ180?

The Phase One IQ180 has a crop factor of 0.64× relative to 35 mm full frame (diagonal 67.2 mm vs 43.3 mm).

What size is the Phase One IQ180 sensor?

55.9 × 37.3 mm (Medium format 53.4 × 40 mm), an area of 2083 mm² — 241% of full frame.

Is the Phase One IQ180 full frame?

No — its sensor is larger than full frame (medium format).

What lens mount does the Phase One IQ180 use?

The Phase One IQ180 uses the Mamiya 645 (flange distance 63.30 mm).

How long can I expose the night sky with the Phase One IQ180?

With a 31 mm lens (20 mm equivalent) the 500 rule gives 25 s.

Sources & licences#

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