Watch for the extra pin rollers on Graflex film backs...
Watch for the extra pin rollers on Graflex film backs...
Having used both Horseman and Graflex roll film backs, I'd assume that there is no difference between their film plane - other than the earlier Graflex backs having a decided lack of planarity in general. By quality I'd choose Mamiya RB backs over Horseman over Graflex "RH" over earlier Graflex backs - but not all backs fit all cameras.
Planarity on the Graflex holders was a bit of an issue, but was improved by the addition of a thin pin roller at each end of the film frame. These rollers were added shortly before the knob wind was dropped for the lever wind. The rollers flatten the belly of the film against the film platen.
Many presume the lever wind was the improvement that signified the better Graflex, but that is not the case.
I have owned knob winds with the pin rollers, and have owned lever winds that did not yet have the pin rollers. The pin rollers are chrome and quite obvious from inside the film back with the film insert out.
Regarding the location of the film plane... my experience has been that all camera backs ranked as being Graflok have the film in the same plane if the back is rated Graflok.
However, I am not clear on the back that is ranked as the "Universal" back, which looks much like a Graflok, but the slide locks are a different length.
The backs that I have used for the flattest film planarity are the late Mamiya Press backs. However the Graflex backs (particularly those made by Singer) which have the pin rollers, hold the film very flat.
This is copied from the Graflex web site:
Roll Film Backs
Back Type: Graflok (usually)
There were two sets of models: the numbered series and the RH series. The numbered series includes the Graflex "22" (2-1/4" sq.) and the Graflex "23" (2-1/4 x 3-1/4, though there was some variation +/- 1/4" in various models.) In the later RH series, there were 3 image sizes: RH-12 (2.25" sq), RH-10 (2.25x2.75") and RH-8 (2.25x3.25") and holders were made for 2.25x3.25, 3.25x4.25 and 4x5" cameras with either Graflok or Graflex backs. The RH-20 appears to be the only back designed for 220 film (2-1/4 x 2-3/4).
The later Rochester-made Graphic roll film backs (with the lever wind, usually marked Singer-Graflex or "Rapidvance") hold the film flatter than Cambo or Calumet backs do; if you like to use wide apertures you might find this significant. By and large, the lever wind units have the rollers and the knob wind version do not, although there are exceptions. The non-roller units do not hold modern film flat: it bows approximately 3/32" towards the film, causing shallow focus at low F/stops. These units are to be avoided.
There may also be a slight overall difference in the film plane between my non-roller and roller versions (at least sometimes).
Horseman has current production Graflok roll-film holders. Since the Mamiya RB67 has a 2x3" Graflock back, you can use can take Mamiya roll film holders on a 2x3" Graphic with a Graflok back. Calumet sells non-Graflok roll film holders, but some people rate the lever-wind Singer-Graflex holders flatter.
A warning for those considering purchasing
3x4" cameras: a conversation with
WD Service about this revealed that there were no roll-film backs mounted on 3x4" inserts with the pin-rollers so critical for film sharpness. The problem may be subtle and hard to deduce at first because it might appear to be just field curvature or some aberration.
The following table lists a number of the Roll Film backs made by Graflex. Manufacturers may be listed as Graflex, Singer Graflex, or General Precision Graflex. Not all roll film backs are listed.
