The Speedgraphics were made famous by press photographers in the 1950s, such as "Weegee" (Arthur Fellig).
With their Speedgraphics with leaf-shutter lenses set to f/8 and large flash bulbs, you could quickly take a photograph of anything without even bothering to focus or set the shutter speed.
has the side-mounted Kalart RF, Graflok back, FP "back-shutter", and Optar 135/4.7 in Graphex shutter... The idea when using the RF is that you extend the bellows out to some predetermined stops on the focusing rails, which are calibrated preset with your specific lens and RF cam setting, so that the image is in focus on the ground glass when it's also in focus in the RF, for a wide range of distances on the bellows.
Then, as you rack the focus knob in and out, they'll track together.
Wide open it's f/3 and very blurry on the edges, and stopped down to about a 1/8" hole is pretty sharp; a great portrait lens.
The curtain shutter lets you time the exposures for lenses that don't have integrated shutters. I checked-out Graflex.org, which is a great site, but unless I missed something, the only dating info they supply is based on the serial number of the lens, presuming the original lens is still on the camera. The reason I mentioned that my RF is a Kalart, is because some Graphics came with Hugo Meyer RF's ,which can approximate a vintage...
that could be achieved with the focal plane shutter.
The Speed Graphic was available in 2¼ x 3¼ inch, 3¼ x 4¼ inch, 5 x 7 inch and the most common format 4 x 5 inch.
Because of the focal plane shutter, the Speed Graphic can also use lenses that do not have shutters (known as barrel lenses). Setting the focal plane shutter speed required selecting both a slit width and a spring tension.
It is said that the automatic diaphragm was invented and patented by a Chicago photographer Torkel Korlin (1903-1998).
The Super D sales did not came up to expectations, reason why Korling decided not to renewal the patent.
Another great thing about your camera is the focal plane shutter.