Big Bertha

Dan Fromm

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What's needed is easy to describe for a straight tube: tube's diameter >= format's diagonal.

A conical tube has to have diameter at rear >= format's diagonal and diameter at front >= lens' exit pupil.
 

billbretz

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David A. Goldfarb said:
Looks like that's a night game, too, which must have been even more of a challenge.
Click to expand...

I think it just looks like a night game because flash was used to light the dim area in the overhang were the photographers were.

I don't know if the cameras would have been practical at all for night games - figure a f5 max aperture, film speed would probably have to be around 6400 to stop any action (and the shutter speed would probably be 1/250th at best. Were those film speeds possible then?

Modern stadium lighting, pro venues included, can range from 1/500th, f2.8 at 3200 to 1/1000th, at 1250, give or take.

Night games were the exception, World Series included.
 

David A. Goldfarb

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Dan Fromm said:
What's needed is easy to describe for a straight tube: tube's diameter >= format's diagonal.

A conical tube has to have diameter at rear >= format's diagonal and diameter at front >= lens' exit pupil.
Click to expand...

Exactly, and looking at how these cameras are constructed, the inside diameter of the tube is likely to be about 7", while the diagonal of the 5x7 frame is about 8.5".
 

steven_e007

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David A. Goldfarb said:
Exactly, and looking at how these cameras are constructed, the inside diameter of the tube is likely to be about 7", while the diagonal of the 5x7 frame is about 8.5".
Click to expand...


Yes, and if the tube was taken right up to the film plane there would be an image circle of 7", hence quite a bit of vignetting on a 5 X 7"

But, the tube stops where the 'box' of the camera starts - maybe 6 inches or so from the film. From this point it can continue to expand to the size of the negative.

As long as the cone of image forming light is still less than 7" in diameter at the point where the tube meets the body, then it shouldn't be vignetted.
 

Joe O'Brien

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What kind of neck strap should I look for when I pick one of these up?
 

1930artdeco

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Here is the other one I use with a standard lens and the modified one with a standard and the 15" lens. They are both ex military, I am guessing from WW II. Newt_on_swings, thanks they are antique Chinese from my Great Grandfather.

Mike
 

jimgalli

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5X7 ~ 4X5 didn't matter as the papers would crop what they wanted out of whatever size neg the photog brought them. I would think 5X7 might increase your "chances".

Here's a page from a 1959 (I think) Burke and James Cat. $800 1959 bucks would stagger you now I suppose

 
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