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bobbotron
22-Nov-2016, 15:21
I've seen a few people make cameras for wide angle lenses with a neat helicoil focusing insert for focusing. I've searched for them a little online but not come with anything useful. Does anyone know where I could I look for sourcing such a contraption, for a 00 Copal shutter?

Pfsor
22-Nov-2016, 15:24
Rodenstock has helical focusing rings for its lenses.

Keith Pitman
22-Nov-2016, 15:31
Seller "jinfinance" on EBay usually has helicoils.

Leigh
22-Nov-2016, 15:51
I have a number of focusing helicoids available, in different sizes.

These are the production tail from the Vivitar Series One lens product line. I bought that whole stock.

These helicoids are new, in factory production packaging, lubricated.
Obviously they are internal components, lacking external pretty housings.

Various sizes are available. I can check if you're iterested.

- Leigh

Bob Salomon
22-Nov-2016, 16:45
A helical focusing device normally is made for specific focal length lenses so that the lens can focus to infinity and they are normally calibrated for focus distance for that focal length lens and has a depth of field scale for the focal length and speed of the lens.
It would be much easier for you to find a helical for a 0 shutter then a 00.

Greg
22-Nov-2016, 17:09
Pentax made a variable extension tube for their 67 camera. It is essentially a helical focusing device that can be easily adapted to mount a lens or shutter on. Thing is you can find them out there for very little money. Front opening is 70mm in diameter. I easily mounted my Copal #1 shutter onto one of their body caps which mounted on the front of the variable extension tube.

Leigh
22-Nov-2016, 18:57
A helical focusing device normally is made for specific focal length lenses so that the lens can focus to infinity and they are normally calibrated for focus distance for that focal length lens and has a depth of field scale for the focal length and speed of the lens.
That is certainly true when discussing an OEM that wants to buy 10,000 or 50,000 of a particular item.

When talking about an individual who wants to buy a single copy, the options are dramatically limited.

He could write up the specs, have the helicoid designed, and send that info to a machine shop to make it.
It shouldn't cost much more than your house.

- Leigh

Corran
22-Nov-2016, 19:08
Are we about to have a discussion about why the Rodenstock or Schneider focus helicals are worth $500 and somehow so much better?

Why is scale of manufacture being brought up?

Here you go, $110 delivered, straight from China, available in 00 size and can be requested with appropriate distance markings for your lens, which I assume is a 47mm or 65mm SA commonly found in 00 shutters:
http://www.ebay.com/itm/272225509054

Oh no, it doesn't have DOF scales, whatever will we do? :)

I don't have one of these but I keep thinking about buying a couple and using them. I have a Sinar Handy that would be fun with a 47mm XL attached. Simple to do with a plain Sinar board and this helical.

The other cheap option is any old busted-up trash 35mm lens. Rip it apart and use the helical. May or may not work. The Pentax 67 helical Greg mentions is also a very nice piece of kit.

Leigh
22-Nov-2016, 19:19
Why is scale of manufacture being brought up?
Because that dramatically impacts price and procurement options.

- Leigh

Corran
22-Nov-2016, 19:24
The manufacture and procurement is already done. Buy them all you want on eBay for just $110 shipped complete with relevant focus scales and sizes, straight from China. Rodenstock/Schneider have their own versions with probably a bit higher fit and finish for their lenses (wonder if they are also manufactured in China? :)). Scale of manufacture has no bearing to the simple question asked.

Corran
22-Nov-2016, 19:37
Scale of manufacture is irrelevant. Back to topic, there are various helicals available that are marked for focus distance based on extension. Infinity calibration is done by the user by setting up the camera to infinity based on their design or needs with the helical at min. extension. These are easily found via the Chinese distributors mentioned or larger manufacturers for specific lenses they make. Hacks from cheap helicals from old lenses are also workable with more work/risk.

OP should mention what lens.

bobbotron
22-Nov-2016, 20:32
Neat. So much great information here, thanks everyone!!!

I definitely have no use/need for focus scale, I'm going to be focusing on ground glass. This would just make my box cameras so much easier to build. It's going to be mounting a 65mm f8 Angulon.

EdSawyer
23-Nov-2016, 09:47
The schneider ones, while expensive, are very nicely made and excellent to use. I expect the Chinese ones are probably not as smooth nor have as many grooves for alignment, but I am not sure. Cannibalizing an old 35mm lens is a nice option too.

DrTang
23-Nov-2016, 11:00
I took a ballpeen hammer to a variable doubler/extension tube thing once - knocked the glass out of it


worked pretty good for like 5 bucks invested

Bob Salomon
23-Nov-2016, 12:54
Neat. So much great information here, thanks everyone!!!

I definitely have no use/need for focus scale, I'm going to be focusing on ground glass. This would just make my box cameras so much easier to build. It's going to be mounting a 65mm f8 Angulon.
That means that the length of the helicoid, plus any adaptors, must be no longer then the flange focal length of the lens, or it will not be capable of focusing to infinity. Make sure that you check this before buying one.

Randy
23-Nov-2016, 18:54
I recently purchased one of the helicoid focuses from China, along with a mounting flange and lens blank from Russia - total was a bit over $100 for all, if I remember. All is very well made. I built a box camera out of a cigar box and a 4X5 back. The focuser allows me to focus my 90mm Super Angulon from about 3 ft to infinity. Perfect for what I use it for. I think I did a post on it in the DIY section a while back.

LabRat
23-Nov-2016, 19:14
I have made focus mts out of 35mm faster (50mm/f1.4) camera lenses for WA LF lenses, but a problem that often comes up is that even with the larger lens barrels, there can be a slight "tunnel" effect, where if a lens were mounted on the front, the extreme coverage can be limited due to cut-off... Even when using a lens with an extended rear element, it might still cut-off and the element might not fit in that barrel...

Another tough lesson was while making a larger focuser from a empty Mamiya press focus mount for a 65mm/f8 SA, was even that would cut-off the edges for 4x5...

If you look for a focuser, find the slimmest one that does not protrude much from the rear, so it does not get in the way...

Steve K

Randy
24-Nov-2016, 06:20
Here is the page (http://www.largeformatphotography.info/forum/showthread.php?45775-Show-us-your-home-made-camera&p=1348487&viewfull=1#post1348487) where I show my box camera with helicoid focuser. The mounting flange and lens blank were from ebay seller rafcamera-dealer. The helicoid focuser, size 17mm-31mm M65 to M65, was from ebay seller hunter20099. The quality of all is very good and as I said, functions perfect with my 90mm SA lens.

bobbotron
26-Nov-2016, 07:09
Here is the page (http://www.largeformatphotography.info/forum/showthread.php?45775-Show-us-your-home-made-camera&p=1348487&viewfull=1#post1348487) where I show my box camera with helicoid focuser. The mounting flange and lens blank were from ebay seller rafcamera-dealer. The helicoid focuser, size 17mm-31mm M65 to M65, was from ebay seller hunter20099. The quality of all is very good and as I said, functions perfect with my 90mm SA lens.

Very cool! Thanks for the info, that's really helpful. I'm bookmarking this discussion for when I get around to doing something similar...

Ceebee
7-Dec-2016, 09:20
Interesting solutions here. Randy does your focuser rotate the lens as you focus or does it remain straight ? might be what I'm looking for, have acquired an Angulon, film holders and lens for viewfinder ( a wide angle converter) now need to make up the body.