I used a cnc machine at my library to make some apertures form my 300mm Imagon. I used an old spare phenolic darkslide. Based on the H5.8 disk, the new disks go to the inside edge of the larger peripheral holes, the middle of the same holes, and the outside edge. That gives diameters of 40.4mm, 46.1mm, and 51.8mm I don't like the standard disks because the funky aperture makes out of focus highlights look like the aperture. Hopefully, I'll have some time to take some photos with the new disks today.
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