Question to identify these

[Reelemup]

I wonder what these plates are for ?
They about 2" in size.
Thanks !

[highpower790]

They look like miners ID tags?

[Reelemup]

They look like miners ID tags?

I don't think so. They all have different hole patterns on them. The one marked 0 has none. See a pattern here?
Some could be missing

[G-forceJunkie]

Since the numbers seem to corospond to the increase in holes, I got to assume they are used to control the flow of something.

[Reelemup]

Since the numbers seem to corospond to the increase in holes, I got to assume they are used to control the flow of something.

They go at a rate of 25 then by 16 bits? Increments then I guess acres...80-160 -320 640 is a section right ? And the x10 and x100 I'm puzzled. My guess is templates in some sort of range finder optics.

[jimmer46]

These look like they could be Waterhouse Stops for an antique camera aperature.

[BKinzey]

Those are slides for a old Sekonic(?) light meter used in film and photography. They are used to match your meter to the film speed/ASA and filters you might be using.

You can see one in this pic.



Most of the numbers, 25, 32, 64, 80, 320, refer to the ASA.

[Loubot10]

Those are slides for a old Sekonic(?) light meter used in film and photography. They are used to match your meter to the film speed/ASA and filters you might be using.

You can see one in this pic.



Most of the numbers, 25, 32, 64, 80, 320, refer to the ASA.

I am in AWE!

[Reelemup]

I found out they were for the Spectra light meter. Thanks all !