How about very light thin shutter with a string and pulley to a weight which is free to fall vertically. Releasing the weight will always cause it to fall at the same speed regardless of the angle of the shutter. No batteries.
How about very light thin shutter with a string and pulley to a weight which is free to fall vertically. Releasing the weight will always cause it to fall at the same speed regardless of the angle of the shutter. No batteries.
Hmm. Not even the original inventors of the guillotine shutter 150 years ago wanted to have vibrations from a weight freely suspended on a standard. Little did they know about practicalities of such a solution. ;-)
Oh, oh, oh! (Raising his hand.)
You could make the slit in opaque cloth instead of a piece of plastic. Then, you could roll that cloth around a spindle above the intended opening, and then attach the free end around a spindle below the intended opening. You could install a spring in the lower spendle, and a catch in the upper spindle. You would wind up the upper spindle until it catches, and then when you release the catch, the shutter opens and closes as the slit passes over the opening.
You could even use a piece of cloth with three slits in it, and wind it to the slit you want to vary the shutter speed.
And you could even attach a clock governor to the spindle to control the speed that the cloth moves. With a couple of different governors, you could provide two speed ranges. Two ranges and three slits would provide six speeds.
Oh, wait...
Rick "thinking of making a lens-board-mounted curtain shutter from the carcass of a quarter-plate Speed Graphic" Denney
You could, yes... But all these solutions with a spring and a spindle have the disadvantage of the initial vibration when you release the catch. I'm sure those who wanted to improve the guillotine shutter went through similar thinking as you do. Then they dismissed the guillotine concept when they understood that the thing must be smaller, not bigger. Then only they turned they attention to the multiple leaves that close and open "a hole" together, with smaller vibrations. That concept was a healthy one and remained with us.
Rick "Originally Posted by K. Praslowicz
Forgo all the timing/angle considerations by just mounting a 4x5 Speed Graphic to the lens board.
Seen here" Denney
Hmm... you could do it by dropping a speed graphic between two boards with an opening cut in them. You might need to reduce friction by removing the handle.Forgo all the timing/angle considerations by just mounting a 4x5 Speed Graphic to the lens board.
Seen here
QED ...
I don't do smileys or LOL's but I'm really tempted here...
Me, too, but here I couldn't resist.
Rick "is there an echo in here?" Denney
Luminous Aero Ektars demand radical solutions!Forgo all the timing/angle considerations by just mounting a 4x5 Speed Graphic to the lens board.
Seen here
I knew the Speed Graphic must be good at least for something...
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