I have that same 300mm lens with a Chamonix 45H-1 with 350mm bellows draw. Am I correct in calculating the closest distance at 2100mm or 6.9 feet?
Is that right?
I'm having trouble with the additional stops required. Could someone give me the guidelines?
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I just packed my 200 and 300 M's for an upcoming trip. I use them for both full 4x5 as well as 6x9 roll film backs. The 300 will also cover 8x10 if movements are minimal. No need to worry about focusing at f/9.
For closeup work, I just use an little plastic Calumet bellows calculator. You place its little target temporarily at the subject plane, focus, then measure the width of that target on the ground glass using the other piece, which tells you both the degree of magnification and how much extra exposure you need. Super simple, and works with all view camera lenses. I think someone else makes something equivalent these days. But several used Calumet ones are on EBay right now. Search "bellows calculator".
The following equation works for compensation in f-stops: Compensation=(bellows extension/focal length)*Log2
I use an emulator for an HP programmable calculator on my cellphone, so it was pretty easy to program it with the only inputs needed being the bellows extension and focal length of the lens. This equation works no matter the units you use, as long as they match (mm/mm, in/in, twip/twip).
It's not just the hypothetical extension, since view cameras allow for movement too, which might offset the nodal point. Then throw in tele design lenses, and yet another possible complication. There are all kinds of workarounds. Punching more batter-dependent buttons sounds the least favoriet to me.
This has it all
https://kennethleegallery.com/html/tech/bellows.php
Sadly, Ebony Camera's website went offline when they shut down, but here's an archive of their "Lens Compatibility Table" https://web.archive.org/web/20170615...es/lenses.html
The Nikkor 300 M requires 290mm of bellows at infinity. That effectively adds 10mm to your bellows, and that adds up!
So, the math is 1/300 - 1/360 (instead of 1/350) and that gets you a close focus of 1800mm.
Movements may decrease this, plus your bellows may not really go to exactly 350mm, etc., but "about 2m" of close focus is not too bad.
https://www.flickr.com/photos/drew_saunders/
A basic Ebony RW45 will easily handle a 360mm lens (like my Fuji 360A) if base tilts are employed, or 300 mm plus without resorting to supplemental base tilts fore and aft, simply via the extension. The more expensive triple extension Ebonys will handle even longer.
Flickr Home Page: https://www.flickr.com/photos/alanklein2000/albums
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