Several years ago I bought a number of meniscus lenses from Anchor Optical to experiment with making a periscopic lens for my 8X10. One pair seemed promising, marked 1.5 diopter. Two of them would give about 13 inch focal length, or about normal length for 8X10. Found an old Wolly RR in a Regno shutter about 10-1/2 inch focal length for whole plate. The cells were about the right size for the meniscus elements. Removed the achromats and installed the menisci.
On the GG, the central image looked pretty good at medium stops. There was a lot of field curvature, so f64 had to be used to get most of the image in focus. The menisci didn't have much curvature, or bending in optics speak. I suspected elements with more bending might give a flatter field.
No images were made, and the project went on the back burner.
A few months ago I decided to try again. By this time, Anchor Optical had disappeared and been absorbed back into the parent company, Edmund Optical. None of their available experimenter's meniscus lenses had the focal lengths I wanted. Surplus shed didn't have anything close, either. On a whim, I searched Ebay for 1.5 diopter lenses and got some hits. Nikon made a series of closeup lenses for the F cameras, described as #0, #1, #2, etc. The #1 lenses are 1.5 diopters. Even better, they seemed to have more bending than the typical closeup lens sets on the market. This might help give a flatter field.
So I bought two. They use a 52mm thread. Next went searching for some way to mount them, and found something that would work, temporarily, my 8X10 f7 Turner-Reich triple in a Betax #4. I knew someday that cinder block heavy lens would be good for something. Just kidding, I like that old lens very much, just don't use it often. With the lens cells removed but the cell spacers left in the shutter, the closeup lenses could be mounted in the cell spacers. The lenses were a bit too small in diameter, so the game plan was to build up the outside diameter with wraps of 1/2 inch wide black masking tape I bought at Freestyle about 15 years ago.
With the right amount of wraps, there was a light friction fit going into the spacers, and more tape was used to hold them there. Aligned the lenses as carefully by eye as I could. There is probably some misalignment, but the results weren't bad, in fact better than I could have hoped. A 58mm yellow #8 filter was taped in front of the front meniscus. There was a two fold purpose here, to make the paper negatives less contrasty and I already had some rough exposure guides for using the filter. The other purpose was to reduce the focus error between visual focus and chemical focus since the lenses aren't color corrected. The spacing between the two menisci was about 2.75 inches.
Below are the starting materials for the project. Two Nikon F #1 closeup lenses, the Betax shutter with the T-R cells removed, and the trusty roll of tape.
The closeup lenses built up with tape
The shutter with the lenses taped in and the yellow filter taped in front
Paper negative image results in subsequent posts.
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