Stu Lieberman said:
In the olden days of photography, the photographer would place himself under a black curtain in order to focus the scene on the focusing glass.
Why don't we do it?
Stu
It wasn't just "in the olden days" as large format photographers today (granted, a fairly rare breed, but there are a few of us) still use a focusing cloth. At least some do, the alternative generally being a focusing hood over the ground glass which has its own, different set of problems.
Here's a photo of me with my 4x5 from 1996. The only reason I'm not still shooting large format is that I moved a lot and now live in Georgia while my darkroom is in Tennessee for now. As soon as I can remedy that I'll take it up again, at least as long as I can get film and paper and chemicals.
Anyway, the bottom line is that if there is stray light it can help, a
lot, but unlike landscape photographers, astronomers are working in the dark already. If you have glare from streetlights or the like, or even a bright moon, I'd suggest trying it. A jacket works, as people have said. Focusing clothes for large format tend to be black on the inside for glare reduction and darkness and white on the outside to reflect the sun's heat, as mine is here, but that's not important for astronomy either.
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