240mm or 270mm tele lens with limited bellows draw

[sanking]

I have a camera with limited bellows draw and am trying to figure out the longest tele lens I can use. The distance from the film plane to the lens board plane is approximately 5 3/4". I have a 270mm tele arton (in Copal S-No. 1) which will not quite focus at infinity, seems to just miss by 5-10 mm or so. Does anyone know if the 240 mm tele arton (or 240mm tele xenar) would work for me?

Sandy

[Mark Woods]

Hello Sandy,

If you take the length of the lens and divide it by 24.5 you'll get the inches equivalent. Example:

240mm/24.5mm=9.44"

I hope this helps.

Mark

[Jac@stafford.net]

Hello Sandy,

If you take the length of the lens and divide it by 24.5 you'll get the inches equivalent. Example:

Typo, but correct outcome.
1" == 25.4mm
240/25.4 == 9.44

(I do the same often.)

[Steve Goldstein]

Sandy, can you get or make an extended lensboard that'll let you focus your 270? That might be cheaper than a new lens...

[Jmarmck]

Are the if they are a "tele" design wouldn't the bellows draw be less?

This might help.
http://www.largeformatphotography.info/lenses-long.html

[Dave Wooten]

Reverse a recessed lens board

[Ken Lee]

If it's a matter of only 5 or 10mm, you could make a spacer ring the same size as the mounting flange, perhaps a bit thicker.

Ideally a machine shop could make one out of aluminum, but if it doesn't have to look fancy, cardboard or wood will do fine. You might have to get a new (longer) set of screws to pass through the extra distance to the lens board, but unless they have to be black, any hardware store should be able to provide those.

[ic-racer]

Extension lensboards in 8x8cm size (for Horseman) are available. The 8x8cm boards can be adapted to just about any of the larger lensboards out there. These have the effect of decreasing the flange-focal distance of any lens.

[sanking]

Extension lensboards in 8x8cm size (for Horseman) are available. The 8x8cm boards can be adapted to just about any of the larger lensboards out there. These have the effect of decreasing the flange-focal distance of any lens.

Thanks. I was focused on getting another lens. Looks like I could get one of these extensions and use the 270mmm tele lens I already have.

Sandy

[Bill_1856]

The 270 Tele-Arton sucks. Look for a 10" Tele-Raptar in Wollensak shutter (cheap, cheap, cheap!).