Antique Mechanical Exposure Meter

An incidentally, for any and all the mechanical engineer/designers out there. How the heck do you go about designing that?

i just bought an instoscope from a fellow appugger the other day ..
it's an extinction meter ... the only problem i have is it uses
the ancient schneider speeds instead of asa/iso values
and the meter only goes as high as the equiv of asa 100 ...
but i just learned today how to do 2x filter factors so it will work just fine :)
it's almost as easy as sunny 11

It is cool... I like gizmos thanks for sharing.

I was just stating a photographic maxim, I have always known, and most of also know that few gizmos other than a light tight box and focusing lens are needed.

Way back in the day there were "light meters" that used some photo-sensitve paper and a timer, to judge the intensity of light to make a more accurate exposure. They were neat little brass and ivory cylinder things with the light sensitive paper inside.

I've been using a Zeiss Diaphot from the 1920s for my b&w exposures. It's pretty nifty!


Kent in SD

I particularly like the Zone 1 to Zone 5 cross-hatching. Maybe this was partially at the root of the Zone System?

I think that is a wonderful device, made in the days when watchmakers and craftsmen made 'computers' out of brass.

It will be compromised by nature of it using an obsolete systems for film speed and possibly aperture as well, but the principle of calculating exposure, rather than measuring it, is sound. The idea still has advocates:

http://www.fredparker.com/ultexp1.htm

The real challenge would be to make a 'modern' version with a familiar ISO speed range. No reason why it shouldn't be a useful tool. I carry around cardboard depth of field calculators and widgets to calculate bellows factor. Never feels right pulling out a modern spot meter with a wood and brass camera.

Not sure I like the 'app' on a phone idea, though. IMHO, If the thing can suffer battery failure - it ain't steampunk! Get the brass out and start filing ;-)

What a beautifully designed widget! I still carry around 1940's and 50's exposure calculators, much lighter(intended) than a meter, more convenient and, easy to use. I would definitly carry one of these if I had one.

Mechanical exposure meter...sounds impossible to me.

In my early engineer career I used Friden mechanical calculators, planimeters, and other neat mechanical devices. I kind of miss them. Batteries never failed. I would like one of these - very neat.

Got to get an extinction meeter... I like the concept. Surprised I haven't run across one in my years of messing about.

Photographed my first summer using the little card placed in Kodak films.