Graflex.org

robcruickshank · Joined: 25 Feb 2008 Posts: 19

Anyone have any idea what the accessory attached to the lensboard is in the photo in this story?
http://www.latimes.com/news/local/valley/la-me-watson28-2008oct28,0,3581624.story

C. Henry · Joined: 13 Dec 2005 Posts: 360

Rob;

I've never seen one but a wild guess is that it is a polarizer or a neutral density filter to modify one of the two images in the top range finder. It looks a bit like the filters on a mariners sextant that were used to darken the image of the sun and reduce reflections on the water when taking sun sights.

C. Henry

robcruickshank · Joined: 25 Feb 2008 Posts: 19

C. Henry wrote:

Rob;

I've never seen one but a wild guess is that it is a polarizer or a neutral density filter to modify one of the two images in the top range finder. It looks a bit like the filters on a mariners sextant that were used to darken the image of the sun and reduce reflections on the water when taking sun sights.

C. Henry

Yeah, I thought maybe polarizer, since it looks a bit like some of the old polarizers that had a little viewing window on an arm, for rangefinder cameras. I couldn't figure out how it would rotate, though.

Les · Joined: 09 May 2001 Posts: 2682

It's a focusing aid. Forerunner of the Kalart Focospot and Graflex Rangelight.
The thing on the top is effectively batteries and a light bulb, the object on the lens board is a lens. Turn the light on and when the filament in the light bulb is in focus on your subject, the subject is in focus.

The trouble with this version is it could only be calibrated for one distance so most photographers set it up for 10 feet or so and let depth of field catch any error. I have one made by Western Photo Products and they called it a Focuspot.

robcruickshank · Joined: 25 Feb 2008 Posts: 19

Les wrote:

It's a focusing aid. Forerunner of the Kalart Focospot and Graflex Rangelight.
The thing on the top is effectively batteries and a light bulb, the object on the lens board is a lens. Turn the light on and when the filament in the light bulb is in focus on your subject, the subject is in focus.

The trouble with this version is it could only be calibrated for one distance so most photographers set it up for 10 feet or so and let depth of field catch any error. I have one made by Western Photo Products and they called it a Focuspot.

Ah! That makes sense. Thanks! A friend of mine does underwater work, and there's a similar, but more high-tech contraption on one of the underwater cameras:
http://www.flickr.com/photos/dryodora/2906709816/