Thinking out loud about single purpose panoramic

[John Bartley]

There's a few thoughts running thru' my head here, so I'd like some reaction to them. I'd rather hear general ideas and thoughts rather than changes to the design measurements, as I've not gone further with this than just the thoughts of how and why it should work and the measurements shown here are just to ease my thinking (which is very difficult for me most of the time ).

1) Assume that I have a lens that will cover my negative without movements and that I know the focal length of this lens.

2) Assume that I am ONLY going to shoot panoramic landscapes, so no movements other than slight tripod head tilting will ever be done.

3) Assume that I am NOT considering portability to be an issue. Size and weight will NOT matter.

Ok, with that settled, here's my thinking;

Any time I take a "normal" (no radical movements) picture from a "normal" (not right close up) distance, my lens usually appears (I've not measured it) to be set close to it's focal length from the film. If this is the case, then if I am only using one lens, the need for a travelling lens stage pretty much goes away and all that's required is a small amount of fine focussing movement? This means that a basic landscape camera can pretty much be a box as long as the box is the right length for the lens.

Sooo ... if I wanted to take pnoramic landscapes on a 10" x 24" negative, all I would need is a 10"x24" film holder, a ground glass holder, a lens that will cover 10"x24" (26" circle) and a light-tight box of suitable length for the lens ????

Am I nuts ?? (don't answer that )

cheers

 

[Dan Fromm]

<snip>
Ok, with that settled, here's my thinking;

Any time I take a "normal" (no radical movements) picture from a "normal" (not right close up) distance, my lens usually appears (I've not measured it) to be set close to it's focal length from the film. If this is the case, then if I am only using one lens, the need for a travelling lens stage pretty much goes away and all that's required is a small amount of fine focussing movement? This means that a basic landscape camera can pretty much be a box as long as the box is the right length for the lens.

Sooo ... if I wanted to take pnoramic landscapes on a 10" x 24" negative, all I would need is a 10"x24" film holder, a ground glass holder, a lens that will cover 10"x24" (26" circle) and a light-tight box of suitable length for the lens ????

Am I nuts ?? (don't answer that )

cheers

Of course you're nuts. So what?

You've characterized where all lenses of "normal" (not telephoto, not retrofocus) construction sit when focused at infinity. More-or-less 1.0 * f from the film plane. So what? And why limit yourself to lenses of normal construction? I mean, if you're contemplating a relativley low-budget DIY project then lenses from aerial cameras should appeal to you.

Until you know the lens' focal length and how much closer than infinity you'll want to focus, you won't be able to calculate how much focusing travel you'll need. FWIW, my rule of thumb for lenses to be used at normal distances is that I want the lens to focus to 1:10; this requires focusing travel = 0.1f, max extension = 1.1f. Extension is film plane to lens' rear node, not to the lens board.

Cheers, have fun,

Dan

 

[jimgalli]

Oh Boy, I get to sell John another expensive lens A cone shaped box with a portion of a 4X5 bellows to give the lens a little focus travel would work well. BTW 10X24 film loads are possible with J&C's EFKE Cirkut camera film. Just roll out 24" and chop. The holders would increase the national debt though.

 

[George Losse]

http://www.glennview.com/vcam.htm
8X20 WIDEANGLE VIEW CAMERA

You might want to check this link out. Its a big page and scroll down to the 8x20 wide angle camera. It uses some sticks which set focus. You can see how the back offsets from a solid part. I thought it was a cool idea.

 

[wm blunt]

Sounds like what Jay Dussard did when he built his 4x10 adobe brick camera.A bit smaller scale but sounds about the same.

 

[grahamp]

In practice I think you would pick the widest aperture you planned to use, and adjust the focus for the hyperfocal distance. i.e. slightly extended from infinity. Since most panoramics are not close-ups (I'm sure there are exceptions), you might want to have a slightly adjustable lens position - hyperfocal for various lens apertures - for maximum utility.

My low-end medium format rotating lens panoramic uses a hyperfocal setting and small apertures successfully. But you do not enlarge panoramics very much!

 

[roteague]

Good ideas all. A bit much for me; I'm going to order a 6x12 Horseman back for my 4x5. I won't do what some of these suggestions will, but will do for my needs - it is probably impossible to get Velvia in 10x24 anyway.

 

[John Bartley]

Thank you ALL for the input, links, ideas and support. It's nice to know that a crazy guy like me is in good company .

Jim - whattcha got .... needs to cover 26" diameter image circle with no movements, cosmetic condition doesn't matter (as you already know ), don;t need a shutter and another one with a Waterhouse slot would be nice as it makes a great shutter slot ... and remember eh? ... I'm a poor, financially destitute, struggling amateur wanna-be photographer who's also a cheapskate (well, the "amateur wanna-be" part is accurate )

cheers

 

[Nick Zentena]

It's just a box camera isn't it?

You don't really need a ground glass for viewing. If it's got basically fixed focus then you can go much simpler.

If you really want to focuss then you can just nest two boxes together. You did say weight doesn't matter-) You can even add tilt by adding a third box to the front. Or a fourth to the rear for rear tilt. The tilt boxes are really lids. Use indirect rise. You can add shift by designing a shifting lensboard. Basically the lensboard is mounted on pegs to the front box. Not exactly the quickest way to work but simple.

Instead of normal film holders I was thinking removable back. Take the back off. Replace it with a film holder back. This could be a simple book type film holder. No ANSI standards for this anyways.

I've had a similar idea for shooting colour paper or film. But it's going to out wiegh a hummer.

One more thing. Everything old is new again. If you have "View Camera Technique" by Stroebel then check out the chapter on the evolution of view cameras. Mine includes a drawing of a box camera with multiple boxes.

 

[jimgalli]

Thank you ALL for the input, links, ideas and support. It's nice to know that a crazy guy like me is in good company .

Jim - whattcha got .... needs to cover 26" diameter image circle with no movements, cosmetic condition doesn't matter (as you already know ), don;t need a shutter and another one with a Waterhouse slot would be nice as it makes a great shutter slot ... and remember eh? ... I'm a poor, financially destitute, struggling amateur wanna-be photographer who's also a cheapskate (well, the "amateur wanna-be" part is accurate )

cheers

John, How about an old Beck Symmetrical 16X20 lens. focuses at about 26". 10X24 should be about the same as 16X20 diagonally. yep, it's an old waterhouse brassie. For $225 I'll include one of my patented JimGalli shutters.