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Jim Graves
21-Sep-2012, 16:51
Has anybody here built a "lens bench" for a shutter timer ... or have suggestions on how to do it?

You know ... a framework with an adjustable lens holder that has a standardized light source at one end and holds the shutter timing device (like a Calumet shutter tester) at the other end.

Jon Shiu
21-Sep-2012, 16:56
Check out JB Harlin's modification of the Calumet Tester.
http://www.jbhphoto.com/articles/article.htm

Jon

Leigh
21-Sep-2012, 20:29
A shutter tester does not require a "bench" in any sense. You need a light source and a way to support the camera/shutter.
I prefer the type with the lens axis pointed straight up, but there are also horizontal styles. The vertical style takes much less table space.

Here's an example of a simple setup (from a UK website):

http://www.appcott.co.uk/VINTAGE6X6/images_shutter-testing/h450_080726.08_shutter-test_Retina1B.jpg

The light source must be a continuous emitter (i.e. thermal incandescent/halogen) as opposed to fluorescent. LED would work if DC-powered.
The light beam should be larger than the maximum opening of the shutter. One of the PAR-series halogen lamps would be great.
The light should be bright enough that the detector does not false on ambient light. A simple desk lamp will work.

The tester should be located such that no fluorescent light falls on the detector when in use.

- Leigh

Sevo
22-Sep-2012, 01:20
The light source must be a continuous emitter (i.e. thermal incandescent/halogen) as opposed to fluorescent.

Actually, modern (high frequency alternated) CFL lamps have less flicker (at least in the range relevant for LF shutters, things will be different if you test shutters capable of 1/50,000s) than a grid AC driven halogen lamp, and the latter can create hard to detect errors when testing speeds near the flicker rate. Simply use DC to drive your light source!