Graflex.org

umitulgen · Joined: 11 May 2004 Posts: 2

Hi all,
I recently made a 6x13cm panoramic camera with the parts of old agfa isolette camera. I am planning on using ysarex 127mm but struggling to find info on flange distance?? I will using this camera purely for landscapes and I need focus to be from closes it can get to infinity. can anyone please direct me to the right info on the net how to complete this procedure or be kind to explain it to me how its done. I know theoratically how it done ie placing a ground glass at the film plane and moving the lens in a distance til the mid range comes into a focus and thats how you set the infinity?? am I right or missing something fundemantel??
thanks very much
umit

Dan Fromm · Joined: 14 May 2001 Posts: 2144 Location: New Jersey

umitulgen · Joined: 11 May 2004 Posts: 2

hi Dan,
sorry that my message was not too clear. I only used the film chambers of the isolette and made a wooden housing for the entire thing. now my camera is 27cm long and 6cm deep. it looks like linhof 612pc!! at least i like to think so. so that means i can use any lens i want on this camera. and I have made deep lens boards to make the distance for the 90mm angulon and 65mm super angulon. but my budget does not allow these lenses just yet.
umit

t.r.sanford · Posted: Tue May 11, 2004 7:12 pm Post subject:

"Infinity" varies with the focal length of the lens, to some extent -- infinity begins a lot closer to a short-focus lens than to a longer-focus one. Depending on where you are, you may or may not have a very distant church steeple or microwave relay antenna mast or water-tower or industrial smokestack in view.

When you don't, you can use an astronomical object. Elsewhere on this site, someone has referred to the "bug-burning" method -- I'd not heard it called that before, but it's an accurate description. Basically, you open the shutter and image the sun on a white card held behind the lens. Adjust the lens-to-card distance until the card begins to smoke...

You also can use the moon, focusing visually, either on a card or on a groundglass (or a piece of artist's matte acetate).

If you need considerable accuracy, e.g. to make a focusing mount, you could rig up a simple instrument by taking a rigid metal ruler, slotting a couple of wooden blocks to slide along its edge, then attaching vertical boards to their back ends (so the bottom of each board rides along the ruler's scale, at right angles to it).

Make a hole in the forward one to hold the lens, and perhaps cut an aperture in the back one to carry a focusing screen -- or simply use a piece of stiff white card for the board, and examine the projected image. You ought to be able to measure flange-to-film distance within a millimeter or so, with no difficulty.

Such a device could be as crude or as polished as your inclination and time allowed.