Here's one of the first batches of photos I shot using homemade lens designs.
It is a very simple lens, two achromat meniscus groups placed behind a stop, around a Compur 0 shutter. Unlike my aplanat design, this one was built around a shutter, giving me aperture control and a leaf shutter. The iris of a Compur 0 is just over 20mm, giving me a maximum working aperture of about f/8. Mounting the elements to a shutter also made it easier to keep them completely parallel and axial.
The elements I use show a ton of SA, a ton of coma, and some astigmatism. The lens is "achromat" in the sense that I do not have to compensate for a shifting point of focus based on what wavelength I want to shoot; to my eye, it is almost good enough for colour, but that will have to wait.
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This design gave me an image circle almost large enough for 4x5 with significant vignetting, and thus large enough for 6x7 with some movements. Here is an example shot with some front rise; you can see that the sharpest part of the image is near the bottom, with the top of the building showing the poor quality of the edge of the circle, and the heavy field curvature.
Shot on-
Homemade 165mm f/8 compound meniscus
Speed Graphic Pacemaker 4x5
Foma panchromatic film
6x7 negative
It is a very simple lens, two achromat meniscus groups placed behind a stop, around a Compur 0 shutter. Unlike my aplanat design, this one was built around a shutter, giving me aperture control and a leaf shutter. The iris of a Compur 0 is just over 20mm, giving me a maximum working aperture of about f/8. Mounting the elements to a shutter also made it easier to keep them completely parallel and axial.
The elements I use show a ton of SA, a ton of coma, and some astigmatism. The lens is "achromat" in the sense that I do not have to compensate for a shifting point of focus based on what wavelength I want to shoot; to my eye, it is almost good enough for colour, but that will have to wait.
--
This design gave me an image circle almost large enough for 4x5 with significant vignetting, and thus large enough for 6x7 with some movements. Here is an example shot with some front rise; you can see that the sharpest part of the image is near the bottom, with the top of the building showing the poor quality of the edge of the circle, and the heavy field curvature.
Shot on-
Homemade 165mm f/8 compound meniscus
Speed Graphic Pacemaker 4x5
Foma panchromatic film
6x7 negative
Category Photography / Scenery
Species Unspecified / Any
Size 1120 x 1400px
File Size 862.8 kB
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