210 f6.8 geronar mc copal bt (42 mt) 5x7 lens

[Compact Diss]

Does anyone know what type/size lensboard I will need for this lens, 210 F6.8 GERONAR MC COPAL BT (42 MT) 5X7 LENS ? I am using a Cambo SCX 4x5. Any help is appreciated.

[Steve Goldstein]

It's in a Copal 1, so you need a board drilled for that size (42mm hole).

[Compact Diss]

Thanks! So I take it that the 42T means 42 mount?

[Compact Diss]

Also, when I find one likes this on eBay, with a "recessed" mount, does that make any difference besides losing a couple of inches of bellow space? http://www.ebay.com/itm/CAMBO-CALUMET-RECESSED-LENS-BOARD-Copal-No-1-42mm-hole-/151367610159?pt=US_Lens_Adapters_Mounts_Tubes&hash=item233e366f2f

I don't know why most lensboard I see are flat, and then I find recessed ones. Not sure what the difference is between the two.

[djdister]

A recessed lensboard is used when using a comparatively short focal length lens, for example, using a 75mm lens on a 4x5 would benefit from a recessed lensboard. All view cameras have practical (minimum) bellows extensions when compressed, so the only way to use a lens with a flange focal distance of less than the minimum bellows length is to use a recessed lensboard.

You should also become familiar with the shutter size holes that you will typically encounter, such as the Copal shutter sizes:

Copal #0 - 34.6 mm
Copal #1 - 41.6 mm
Copal #3 – 65 mm

[BradS]

The '42MT' is KEH notation for "it mounts in a hole with 42mm diameter". That, in turn can be understood to mean that it is likely a Copal #1. So you'll need a Cambo lens board that with a 42mm (about an inch and 5/8) diameter hole in it.