Hi Joe, that's exactly the same phenomenon. I have even seen "glasses" that consist of nothing but a grid of pinholes in place of lenses- and by golly, they do work, up to a point. The trade-off for increased depth-of-field and better focus when using a pinhole is ultimately a loss of maximum resolution, since that is a function of aperture. But most of the visible detail perceived for reasonable 1X vision doesn't require large aperture. I believe it was Kurt who posted the Mars-moon appulse notice, I can't take credit for that one.
From: Joe Bauman <bau@desnews.com>
Chuck, re. pinholes: When I was a junior high kid in Florida about 1960, I had to take a hideous TV history class, with what seemed like 350 other kids stuck in a huge auditorium. I had bad vision and no glasses. Anyway, to watch the TV screen from my distant seat, I would curl my index finger tightly, holding it in place with my thumb, and peer through the hole. In effect, I shut down the f/stop and increased the depth of field, bringing the picture into a better focus. It was uncomfortable and tiring and I missed a lot of what went on. Anyway, maybe that's part of what you did with the pinhole, improve focus, besides cutting down on the glare.
Thanks so much for these reports. When I got home from work last night (earlier than usual for a Sunday night because I had to begin my coverage early), I tried to get a shot of the moon-Mars combo you told us about. I used a telephoto and tried different exposures. Even at 1600 ISO, it was a long exposure to get Mars to show up at all. That meant it moved around a bit. I lay flat on my back on the driveway and propped an elbow on the cement for stability, and I did get one photo that isn't awful. I stepped up exposures, checking to see when I could detect Mars. The first one that worked had the moon overexposed, since Mars is so much dimmer from this part of the solar system.
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