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buggz
7-Apr-2012, 14:11
Hello,
What would be the choices for the longest FL that would cover 4x5 ?
I see 600 Fujinons.
Any others?

Lachlan 717
7-Apr-2012, 14:19
You'll need to post how much bellow extension you have before this can be answered.

David A. Goldfarb
7-Apr-2012, 14:20
How much bellows do you have, and how big is your lensboard? There's the 1800mm Apo-Nikkor, and there are other process lenses that are really long like a 70-inch Artar. These lenses cover much larger formats than 4x5", but can certainly be used with 4x5"if you can physically mount them and have enough bellows to focus.

The longest I've used is a 750mm cell from a Busch Vademecum casket set on a Sinar P with two tripods, an 8x10-4x5" reducing back, and an extra long 40" bellows. It was interesting as a test to see what the image looked like with that cell, but not an experiment I've repeated.

Mark Barendt
7-Apr-2012, 14:29
The coverage issue is for short lenses not long.

The problem with longer lenses is having enough extension. At 600mm you need at least 24" of extension to use the lens and a fair amount more to make it easily usable.

buggz
7-Apr-2012, 16:35
Oh, I see. Still learning.
I have a 4x5 Sinar f2.
I have the base rail, and a 10" extension.
The bellows is the standard one, and it extends all the way out using these two extensions together.
Not certain how many extensions one can add.
I know I would have to add another standard and another standard bellows for crazy long stuffs.
Not certain how practical a double bellows extension set up would be.

buggz
7-Apr-2012, 16:36
That's wild.
Yeah, I thinking about something not too unwieldy.


The longest I've used is a 750mm cell from a Busch Vademecum casket set on a Sinar P with two tripods, an 8x10-4x5" reducing back, and an extra long 40" bellows. It was interesting as a test to see what the image looked like with that cell, but not an experiment I've repeated.

buggz
7-Apr-2012, 16:54
So, looking the other way around, how much length does a 600mm lens need?
600 millimeters = 23.62 inches, is it as simple as that?
No, I have NOT read all these books I seem to be "collecting".
I REALLY NEED to.

Dan Fromm
7-Apr-2012, 18:08
A camera with long extension can be very unsteady.

The standard solution is to mount the camera on two tripods. Joerg Krusche, who sometimes posts here, does this and in this thread David A. Goldfarb described this trick.

Robert Polidori (see http://www.cnngo.com/hong-kong/play/robert-polidori-257129 ) has another solution. Two Manfrotto 244N Variable Friction Magic Arms, each clamped to the rail and to a tripod leg.

I did this for my Baby Bertha (2x3 long lens SLR) project. I've shot Baby, encountered vignetting problems that are due to the SLR's internals but in Baby's last incarnation had no stability problems.

Leigh
7-Apr-2012, 18:28
Not certain how many extensions one can add.
The Sinar F2 is a perfect camera for long lenses. You can add as many bellows as you wish.
All you need is a multipurpose standard at the junction of two bellows, and of course extension rails.
Sinar makes a supporting base that holds two rail clamps, so you can distribute the weight and have better support.


So, looking the other way around, how much length does a 600mm lens need?
The parameter you're interested in is the Flange Focal Length (FFL).
This is the distance from the film to the front of the lensboard when the camera is focused at infinity.
For long focal length lenses, the FFL is generally shorter than the optical focal length, sometimes by a significant amount.

The other parameter of interest is the diameter of the Image Circle (IC). This is a measure of the lens coverage.
For a lens to cover the film at all, the IC diameter must at least equal the diagonal of the film (~163mm for 4x5).
The larger the IC, the greater the range of movements (rise/fall, shift, tilt, swing) possible with the lens.

Watch out for the IC spec on "macro" (aka makro) lenses.
The value given is usually for life-size (1:1) reproduction, which is twice the diameter of the IC at infinity focus.

The FFL and the IC are published on all modern lens data sheets, and can be found online from many sources.

- Leigh

Corran
7-Apr-2012, 19:36
The 720mm Nikkor-T from the 360/500/720 set can be used on a Chamonix with extension attachment. If you got the bigger 600/800/1200 set you might be able to squeeze the 800mm on, I don't know. That's probably the longest you could get without a lot of hassle. As stated, an 8x10 with 4x5 reducing back would be a way to get longer but that's not really the same thing in terms of portability/ease of use...

David A. Goldfarb
7-Apr-2012, 19:39
That's wild.
Yeah, I thinking about something not too unwieldy.

I don't have a photo of the setup, but here's the shot with the 750mm Busch Vademecum cell, if you're curious--

71557

f:83, 32 sec., medium yellow filter, 4x5" Polaroid Type 55 developed normally for 20 sec.

Detail:

71558

ic-racer
7-Apr-2012, 20:46
So, looking the other way around, how much length does a 600mm lens need?
600 millimeters = 23.62 inches, is it as simple as that?
No, I have NOT read all these books I seem to be "collecting".
I REALLY NEED to.
You will need about 600mm to focus at infinity and 1200mm to focus 1:1. So, depending on how close you want to get to your subject, the bellows draw needed will fall between those extremes.