Mike, that's an idea... It would likely only work for the 6.8 variants, as the ƒ/8 sticks out quite a bit.
65mm
90mm
Mike, that's an idea... It would likely only work for the 6.8 variants, as the ƒ/8 sticks out quite a bit.
It would be much easier to throw in a backpack if the lens was protected - camera, light meter, some film holders and a cloth in the backpack, tripod over your shoulder. And I'd envision people buying a less expensive lens to more or less dedicate to this camera, in which case they'd probably get a small lens.Originally Posted by Ben Syverson
Mike → "Junior Liberatory Scientist" ✌
Hello Ben, I think this a great idea. I don't know if I miss it or not but will it have a ground glass with some sort of bright screen? I have a 90 SA just sitting around and a horseman 6x12 back. This would make a great panoramic as well as 4x5 camera on the GO. I think that there should be some sort of locking setup in the mount so that you don't screw the lens out of the camera while focusing, that happen to me once with this type of mount. But i LIKE IT!!!
Not at all - "excess" coverage at f/22 means adequate coverage at wider apertures. Yeah, focus challenges and all that; pick your poison, as far as which constraints bother you the most.
Anyway, this is all sounding very encouraging.
Why not take a leaf from the Fotoman/Titan book and have interchangeable cones, make the back a standard. One minor problem is different lens have different film to flange distance which will mean the focus ring will need to be adjustable the infinity point. I had a DIY one with a 90f6.8 with fixed focus, great to use.
Cheers Shane
I would like to see a 90mm F/6.8 version.
Thanks,
Gabriel
Both of these points have already been covered. The molding for this is so simple that it's just easier to provide two separate cameras for the different focal lengths than to mold in a light-tighte and mechanically sound cone interface. At $100 price point, I'll just buy cameras for both focal lengths. The whole camera is only slightly larger than a cone by itself would be. I think Ben is correct to keep it simple and as cheap as possible. The more flexible you try to make it, the more it ends up costing like a Titen or a Fotoman.
And, yes, Ben has said the focus scale will be adjustible for position to account for different flange focal distances.
Rick "taking some measurements" Denney
Hey Ben since you already have the pinhole technology down you might a well make a pinhole lens for it.
Mike → "Junior Liberatory Scientist" ✌
Okay, here are some lens dimensions for lenses that will be well-suited but that you may not have on-hand to measure.
The Graflex Optar W.A. 90mm f/6.8 is mounted in a in a Graphex No. 1 shutter, which has a mounting thread of 1.1775-40. That fits snugly in a 1.19" hole (30.2mm). A Compur/Copal No. 0 shutter requires a 34mm hole. My Optar includes flange that has a ridge that will nestle snugly into a 34mm hole when used as a retaining ring. This is probably the standard flange for this shutter. That ring also makes it fit snugly into the larger standard hole for the Graphex No. 2 shutter used for the standard 127mm and 135mm Optars. (Graphex = Wollensak Rapax, and Optar = Wollensak Raptar.)
The Optar W.A. 90, when mounted, pokes 3/4" (20mm) out the front of the lens board. There is no filter ring--the barrel will vignette with any filter. There is not enough surface for a Lee-type adapter that uses set screws. Thus, a lens cover with a large filter ring (say, 77mm), that is 1" deep would cover this lens and provide a way to use a filter or screw-in shade.
The 65/8 Super Angulon is mounted in a No. 00 Compur shutter, which, as I wrote before, can be mounted in a standard 34mm No. 0 hole using a cheap adapter. When mounted, the lens pokes out the front by 34mm, plus lens cap. It has a standard 49mm filter thread. The barrel is 2" (51mm) in diameter. So, make that 77mm-wide lens cover 1-1/2" deep, and it will cover this lens, too, and still not vignette the 90.
I have tested this lens with 4x5 Fujiroid, and it has remarkably little falloff. I have the center filter for it, which is not wider than the front barrel and thus will probably vignette a bit, but I will not use it. Fujiroid is pretty narrow; I would expect falloff to be as severe with it as with transparency film.
The 65/5.6 Super Angulon is much larger, of course. It is mounted in a No. 0 shutter, and it pokes out the front 1.65" (42mm) without cap or filter.
The controls on the No. 0 shutter dictate the overall diameter for lenses that use it, unless you start putting center filters on them. An Angulon in a No. 0 shutter would have the same controls, and would need 86mm of inside diameter to clear.
With its Center Filter III with cap, the 65/5.6 is 4" in diameter (91mm) and sticks out 56mm. That would accommodate a 90/5.6 Super Angulon without center filter, which has about the same depth but is maybe a quarter inch less big around.
I don't have a 90/8 SA or an 90/6.8 Angulon, but maybe you do or someone else can provide those measurements.
Providing the front cover to accommodate the 65/8 Super Angulon probably makes the most sense, though Oren may still lobby for enough to cover the 90/8. Given it a threaded filter opening would be slick, and then a cheapie snap-in cap or metal filter cover could provide the lens cap. Your design looks as though it would accommodate that if you threaded the outside of the round flange behind the focuser. That would leave enough room, perhaps, to coil up a short cable release inside the cap for smaller lenses, though those can also be stored inside the camera body.
Rick "figuring too much data is better than not enough" Denney
No FL lobbying from here - I can see uses for either a 65 or a 90 version. Looks like opinion here is pretty evenly split. So I think Ben should just go with whichever one will be easiest/fastest/cheapest to bring to market - and if there's no difference, then whichever he prefers himself.
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