[LargeFormat] rest

[Clive Warren]

At 5:13 pm +0200 29/1/01, Dave Southwood wrote:
>is it bad for an average l - format lens to left in the shutter open 
>position ('T') with the diagphragm dilated while not in use? its 
>very convenient but seems as though, when its cocked, the mechanism 
>is under some duress and might lose its original tensile properties

Leaving the shutter cocked is probably a bad idea as the main spring 
which operates the shutter is under tension and could eventually 
stretch.  This will affect the shutter speeds - ie they may become 
longer over time.

Generally, the best way to store a shutter is with the speed setting 
at something low eg 1 second or B or T and the shutter UN-cocked.

In practice, most shutter speeds are off anyway but there is little 
point in making the situation worse if you can help it. This is 
particularly true for older shutters where the spring has probably 
lost some of its tension anyway....

-- 
All the best,

             Clive Warren   http://www.f32.net
                            Large Format travel and stock photography