P3D Re: My "Good Deal" Revere

["Greg Wageman" <gjw@xxxxxxxxxx>]

From: Mr.Lizard <mrlizard@xxxxxxxx>


>    The camera I purchased at an antique show, last March, may have
some
>problems.  I'm no expert with exposure, but, I used the hints on the
camera
>back, and sometimes the info on the inside of the film package.  I
didn't
>expect perfection.  Unfortunately...
>A number of the shots were very very overexposed.  Nearly all washed
out.

I trust you meant the camera bottom?  The backs of my Reveres are
covered in brown leather, but the base has an exposure table.

Unfortunately, that exposure table is calculated for the ASA 10 slide
film that was available at the time of manufacture.  If you exposed even
100 ASA film using that as a guide, you would have been more than 3
stops overexposed.  Print film has the latitude even for that amount of
overexposure, but slide film will be quite "thin".

>    Could it be that the shutters are sticking open for a few fractions
of a
>second too much, but only intermittently?  Other shots, at first
glance,
>seem okay.  I'll try mounting some of the good ones, over the weekend.


For shutter speeds under about 1/50th, the Revere shutter (like many
others) uses a clockwork escapement mechanism to delay the shutter
closing.  (You can hear this mechanism "tick" or buzz when you set the
dial to the slow speeds, as well as when you fire the shutter using
one.)  The lubrication used on the gears tends to become gummy with age,
so you will find that these slower shutter speeds tend to get *really*
slow, relative to the higher speeds.  E.g. the 1/2 sec. speed can easily
turn into one, two seconds or more.  A good CLA by, for example, Jess
Powell will clear up that problem.  If you used the ASA 10 table, that
plus a slow shutter could easily have you 4+ stops over.

     -Greg W. (gjw@xxxxxxxxxx)




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