At the first glance the Crown Is identical to the Speed
Graphic,
however it misses the
focal plane
shutter and thus the winding mechanism visible on the right side of the
camera
which is the first eye catching recognition to distinguish between Speed and
Crown Graphic Camera.
The lack of this Focal Plane shutter
makes the camera lighter in weight and minimise the depth of the body.
The Graphex Front Shutter limits the exposure time. While the Focal Plane
shutter exposure time is as high as 1/1000
the Crown front leaf shutter just manages 1/400. Beside that, the camera cannot
be used with tube* lenses as these are not being fitted in a leaf shutter.
Find
out the differences between the Crown Graphic and the
Speed Graphic.
The shutter on the front is tripped when pressure on the body release is transmitted by a Bowden cable, actuating the shutter release arm next to the shutter on the standard.
At the first glance the shutter release is a simple button, however, the shutter release appears to be quite an ingenious, well designed and reliable assembly which finds it place on the right side of the camera body . The camera house is made of special Honduras mahogany wood and dovetailed to resist heavy climate changes and rough treatment. One of my Large Format camera friends Barend Jan van Spaendonck could not resist the challenge to take a look behind the leatherette to find out how the build in shutter release mechanism works. First of all he removed the plate of the release slide as well as the trim on the front, then he started to peel off the leatherette, beginning at the bottom side of the body, using a cotton tip with some drops of contact cement solvent or acetone to remove the glue.
After successfully removing the leatherette, he unscrewed the plate assembly body release mechanism. It exists out of a plate d - the trigger release a - spring c and finally the cam b to operate the Bowden cable inside the body.
Squeezing the body release lever a moves the cam which is connected to the Bowden cable inside the camera body, which controls the release assembly on the front standard (photo on the right). The cable pulls the rod down and the release arm trips the shutter.
To make it a bit more complicated, the Speed Graphic is equipped with a focal plane shutter as well. The focal plane shutter
too is controlled by the build in shutter release, but previously the shutter must be selected by the shutter selector slide on the black crackle hardware on the right side of the camera. Selector reads:
Trip, Back and Front.
Apart from that, the release button is connected to an electric circuit to disable the function of firing when not using the build in release button.
Safety First
That means that winding the focal plane shutter does not fire the flash, nor tripping the shutter with the slide selector will activate
the flash.
Only tripping the build in release button flashes the bulb.
Only the Speed Graphic electric circuit includes the safety
provision coupled to the release button.
Photos copyright Barend Jan van Spaendonck and Jo Lommen