SL2 DoF vs App DoF

[spassig123]

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Can someone check the Deep of Field

Camera: Leica SL2

Lens: APO Summicron-SL 1:2/90 ASPH

Display SL2

f 2.8

Back: 6.4

Distanz: 6.2

Front: 6.0

f 20

Back: 7.8

Distanz: 6.2

Front: 5.2

App Lumariver DoF

f 2.8

Back: 6.25

Distanz: 6.2

Front: 6.15

f 20

Back: 10.4

Distanz: 6.2

Front: 4.43

Edited January 30, 2020 by spassig123
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[01af]

So it seems the Leica SL2 assumes a maximum circle-of-confusion diameter of approx. 1/3000th of the format's diagonal rather than the usual 1/1500th. Debatable.

The Lumariver app obviously uses 0.004 mm (4 µm); i. e. the the sensor's pixel pitch—which is a daft approach to depth-of-field. Not recommended.

[spassig123]

@01af

Thanks for feedback.

I found in DoF setting Pixel Pitch = 6 um.

(I don’t find the right symbol for u on iPad)

My calculation is.

Leica SL2 f2.8 Distance Back - Front = 0.4 m.

Leica SL2 f20 Distance Back - Front = 2.6 m.

App DoF SL2 f2.8 Distance Back - Front = 0.1 m, less as SL2.

App DoF SL2 f20 Distance Back - Front = 5.97 m, more as SL2.

There is confusion if I read the result right from Leica and App.

Jochen

[01af]

vor 18 Minuten schrieb spassig123:

... less than SL2. [...] more than SL2. There is confusion ...

Oh yes, you're right. There's some inconsistency ... I was looking at the f/2.8 results only. And my calculations—or actually, estimations—of the maximum COC diameters used by Leica and Lumariver are somewhat tongue-in-cheek and only approximate.

Maybe the Lumariver calculation for f/20 takes diffraction into account which would spread out any COC, hence increasing DOF. Just a speculation, though, I haven't checked the numbers ...