Zone focusing with 50 lux asph

[lars_bergquist]

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One reason why d.o.f. scales are often impractical is that the subdivisions of the d.o.f. scale is so much finer than that of the focusing scale, that they simply don't work together. Here is my 50mm Summilux ASPH. The last meter marking before infinity is 5 meters. (OK, I don't think in feet.) Even if we accept those 1920's computations, all depths of field up to f:11 fits inside that huge gap. Change the computation for a maximum acceptable c.o.c. to something like 0.015mm, which would be a minimum, then you would need a strong magnifier to read them. And a distance scale to go with it would also need a strong magnifier because it would have to be equally finely divided.

 

So, ye Gnomes of Solms: Abolish d.o.f. scales for lenses longer than 35mm. With these lenses, change the computation to a realistic value. Mark the d.o.f. scale "Ø 0.15mm". Reduce it to a couple of useable values like f:11 and f:5.6 with 35mm, maybe 8 and 4 with a 21mm lens.

 

Or is that brew too strong for your throats?

 

LB

[jaapv]

Here I have to remind you of the forum mantra that automation, scales and such are no replacement for the photographer's brain. i'm not sure abolishing the scale is a good idea, as they provide a reference point, depending on focus throw etc. Butit might be a good idea to leave out the apertures, as they convey a false sense of precision. Just numbering as some kind of ruler scale might be better.,

[SJP]

Keep the scales exactly as they are, as a relic from the past, just like the whole rangefinder concept.

 

I used my M2 a few times recently and the challenge of shooting in the dark i.e. relying on your brain to choose exposure, focus etc. makes it a strangely exciting experience compared to digital. There is the suspense of whether the pictures will be OK or whether you have just tossed 15 euro of film & development cost in the can. The pictures were exposed correctly in 30/36 shots, which is OK I guess.

 

Anyway, the quirkiness of the Leica M experience forces you to think - that is part of the fun.