I’ve got several kontur finders, both 35mm and 6x9. The frame lines are clear areas on an opaque background. It would probably be easy to make using Kodalith film, old tech or go modern with computer and transparent material to print on.
I’m not an optics expert just a person who spent his working years doing neat science stuff in research labs. After giving some thought to the subject of Kontur finder design I came up with a couple ideas for a modern version.
First the high end… A small screen such as are common in mirrorless these days. At the time I was experimenting low resolution stuff was easy to get. You don’t need hi res, you’re only generating thin frame lines. Just add a suitable lens, case and foot and it should work.
What I wasn’t able to do was write the code to generate the frame lines. A friend was supposed to assist, but got diverted. Of course having frame lines in software means easy adjustments for focal length, etc. Nikon DSLRs have pins on the shoe that send distance and focal length to control their zoom flashes. Trying to photograph birds in flight is especially difficult with a long lens. A zoomable kontur would be very useful. I got a simple working prototype, but never took it farther. At one point I wanted to enlist Tom A.s help with details, sad that he passed before it could happen.
Second the low tech route. Engrave the frame lines on a thin piece of transparent plastic, back this with an opaque material. A small bright light LED at the edge lights up the lines. It’s even possible to stack several of the clear sheets and get different lines with the flip of a switch.
I was able to source the optical parts fairly quickly. I got several magnifiers that are designed for measuring thread count of fabrics.
Still got all the bits, should pass them on to someone with the skills and time.
If Kontur finders have gotten you curious there’s an easy way to see the effect.
If you’ve got an M Leica or similar, cover the view window on the front with something that blocks all light. Black electrical tape that you’ve pressed your thumb against a few times works well. You just need to block the light. Also cover the range finder window.
If you’ve got an X-100 type cover the window as above.
Now hold the camera up to your right eye while keeping the left eye open. What you will see are the frames floating in your field of vision. The brain cleverly puts things together. The frames you see will be wrong for the focal length. The lines you see divided by the finder magnification is the apparent Kontur focal length.
Crazy ideas from an old guy. ;-)
