Microsoft Lumia 950 XL: Crop Factor, NPF Rule & Hyperfocal Chart

Name: Microsoft Lumia 950 XL
Brand: Microsoft

The Microsoft Lumia 950 XL uses the built-in lens (fixed-lens camera) with a 6.02× crop factor (about 6.0 × 4.0 mm sensor). Below: equivalent focal lengths, maximum shutter speeds for sharp stars, a hyperfocal distance chart and how to check the shutter count.

Mount

Fixed lens

Crop factor

6.02×

Sensor (approx.)

6.0 × 4.0 mm

Circle of confusion

0.005 mm

Equivalent focal length & field of view

Lens focal length	Full-frame equivalent	Diagonal FOV	Horizontal FOV
8 mm	48 mm	48.5°	41.1°
10 mm	60 mm	39.7°	33.4°
12 mm	72 mm	33.4°	28.1°
14 mm	84 mm	28.9°	24.2°
16 mm	96 mm	25.4°	21.2°
18 mm	108 mm	22.7°	18.9°
20 mm	120 mm	20.4°	17.1°
24 mm	144 mm	17.1°	14.3°
28 mm	169 mm	14.7°	12.2°
35 mm	211 mm	11.8°	9.8°
50 mm	301 mm	8.2°	6.9°
85 mm	512 mm	4.9°	4.0°
135 mm	813 mm	3.1°	2.5°

Multiply by the 6.02× crop factor for the full-frame equivalent field of view.

Milky Way exposure: NPF and 500 rule

Focal length	NPF @ f/1.8	NPF @ f/2.8	Strict NPF @ f/2.8	500 rule
8 mm	16.9 s	21.2 s	11.6 s	10.4 s
10 mm	13.5 s	17.0 s	9.3 s	8.3 s
12 mm	11.2 s	14.2 s	7.7 s	6.9 s

NPF = (35 × f-number + 30 × pixel pitch) ÷ focal length, with a pixel pitch of 2.4 µm (typical for this format — exact resolution not in our database). The strict version (Michaud's detailed NPF for the galactic core) gives pin-point stars at 100% view; the 500 rule is a loose rule of thumb that shows trailing on modern sensors.

Hyperfocal distance chart

Focal length	f/2.8	f/5.6	f/8	f/11	f/16
10 mm	7.2 m	3.6 m	2.5 m	1.8 m	1.3 m

Focus at the hyperfocal distance and everything from half that distance to infinity is acceptably sharp (circle of confusion 0.005 mm). Use the hyperfocal calculator for other settings.

How to check the Microsoft Lumia 950 XL shutter count

Not every maker writes a shutter count into image files. Try `exiftool -a -G1 -s image` on an unedited original and look for a tag containing "Shutter" or "Count".

ExifTool tag: (varies). Always test an original, unedited file straight from the card.

Where to buy

Compare new and used prices at these retailers:

B&H Photo Amazon KEH (used)MPB (used)

FAQ

What is the crop factor of the Microsoft Lumia 950 XL?

6.02×. A 24 mm lens frames like a 144 mm lens on full frame.

What shutter speed should I use for the Milky Way with the Microsoft Lumia 950 XL?

With a 8 mm lens at f/2.8, about 21 seconds keeps stars sharp (NPF rule).

How do I check the shutter count on the Microsoft Lumia 950 XL?

Not every maker writes a shutter count into image files. Try `exiftool -a -G1 -s image` on an unedited original and look for a tag containing "Shutter" or "Count".