This post will briefly explain how I set up TRF Speed and Crown Graphics to focus at one fixed distance, much closer than factory cams will allow. I call it the "Big Shot" configuration because Polaroid once marketed a portrait camera which operated in a similar fashion.
The technique did not originate with Polaroid, however, but was used by press photographers on Kalart RF equipped cameras before WWII.
I cut a Big Shot cam for the TRF by "nosing off" the end of the cam at the near focus end. First I move the tripod-mounted camera in on a focus target while I watch the image on the ground glass. When I have the camera in focus for the desired head and shoulders composition, I lock everything down. At this distance, the Rf has gone beyond its range and the arm on the track no longer contacts the Rf plunger. Up in the mechanism, the cam follower rests on the low end of the cam and the RF image, if you looked, would indicate a distance much further away than that at which the camera is actually focused. I cammed my 150/5.6 Fujinon to focus at 27" from the lens board.
Next, I remove the cam and start filing off a nose on the low end. I work slowly and carefully, frequently reinserting the cam to check my progress. When the RF images converge on the target, it's done! I place a witness mark on the track to line up with the infinity mark on the focus scale so I can quickly set up for Big Shot again whenever I want.
This leaves only the problem of accurate viewfinder composition to be solved. Fortunately, Graflex has provided an excellent open frame finder, adjustable for parallax. It is very accurate for frame size with lenses of normal configuration (non-telephoto), but parallax compensation at the close focus Big Shot distance requires extra adjustment. Pull up the frame finder on the front standard fully as usual, but then push down the lower part of the frame to be flush with the top of the front standard. With my 150mm lens, if I then set the peep sight to 15 feet, I can make an accurate composition. The camera is focused, like the Polaroid Big Shot, while hand-held, by moving in and out from the subject while watching the RF image. Once focus is attained, be sure to have your subject look into the lens of the camera, and not into your eye on the peep sight. A well-calibrated optical range finder is the most accurate way to focus, so the lens can be used wide open with confidence that the subjects eyes will be sharp if that is where you focused.
Attached is a scan of a full frame print from a 4X5 color negative. My model, Maria, and her dog Honeybear were illuminated late in the day by a Vivitar 285 with bounce card mounted on the hand-held camera. Like the old Polaroid Big Shot with its flash cubes, flash exposure is always the same because distance is always the same. The 285 with bounce card on full power manual gives me f11 on 100 ASA film.
I have just finished setting up a superb 210/5.6 Fujinon W that I purchased from JimmyCreative here on the forum, and I will post results from that soon. 210mm looks like the longest lens that will be practical for Big Shot on the TRF, it is focused at 33" from the lens board.
There are of course, many other uses for the Big Shot camera besides portrait photography.
Neal
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