"murrayatuptowngallery"
wrote in message
oups.com...
It arrived today.

I learned it has a Waterhouse slot, 2 air cylinders and
springs that
look as modern as any (I guess I never really thought
about helical
tension springs looking the same).

Number (serial?) on the back, nothing identifying the
shutter it yet.

f/stop scale marked 6.2 - 45, so it must be newer than US
stop
style..but Waterhouse stops certainly SEEM older than
'real' f-
numbers.

The scale about the f-stop scale must tell something about
the
Waterhouse stop required, otherwise I don't see a point to
labeling
the lens body if the Waterhouse stops are individually
marked and
spend more time external to the lens than part of it.

I'm easily impressed - little lenses that throw large
images.

The shutter could be any of several. One of the
cylinders is the speed regulator, the other to trip the
shutter with an air hose. It should have a hose fitting on
the bottom.
If it has a stop scale it must once have had an iris
diaphragm. A slot may have been cut later for Waterhouse
stops. About the only lenses I know which have both an iris
and a slot are process lenses where the slot was used for
special stops for process work or for filters.
If this is a standard make shutter it may be possible to
fit the cells into a newer shutter made by the same company.
US stops are calibrated in terms of relative exposure
time but are otherwise arbitrary. US-16 is the same as f/16
so US-8 equals f/11, US-4 equals f/8, etc. The stop scale
could be for either system but, assuming the lens is some
variation of the R-R lens its likely to be US stops.


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Richard Knoppow
Los Angeles, CA, USA