Large format lens with helicoil focus.

[minhnguyen9113]

Hi

I am in a project building a 120 roll film panorama camera and

looking for a source where I can get some helicoil focus lens.

Would you direct me to a lens source who sale those lens, any help

from the forum will be appreciate. Thanks

[troyammons]

I think B+H sells them and maybe Schneider.

[michael_briggs2]

<p>Here is a previous thread that discusses the versions of Helical Focusing Mounts that are currently manufacturered by Rodenstock, Schneider and a Chinese company: <a href="http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00DYDm">http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00DYDm</a>.

You should be able to order the Rodenstock and Schneider versions from any excellent retailer. B&H has them on their web page (search for "Focus Mount"), as does Robert White (under "Large Format Lenses").</p>

[ralph_jensen]

There's a 65mm helicoid Schneider on Ebay right now, auction #7558520711.

[rachel_kinoshita]

I purchased a 65mm and a 90mm helical focusing mount from the eBay seller jinfinance and have been very happy with both. I mounted a Schneider 65mm Super Angulon f5.6 in one and a Schneider 90mm SA f8 in the other. The focusing scales are a little off, but close enough.

 

Thanks,

Rachel

[minhnguyen9113]

Hi. Thanks for your responses, I know where to look for a helical mount now. I built a 6x15 panorama base on a Polaroid 900 body the lens is 105mm, 4.5 and I try to use hyperfocus set at 25 feet.

Hopefully at f 16 the pictures come out good. I try a roll this weekend and show you what I got. Thanks again, Minh

[dan_fromm2]

Minh, good luck. Odds are that your 105/4.5 won't cover the format. Please let us know how it does.

 

Cheers,

[razzledog]

I also use helical focus 'devices' from my friend Rong Jin. They are quite well made and handle the job nicely. A damn site cheaper at $119US, even if the scale is not correct for the lens used. A quick spin in the lathe removes the markings and I then introduce my own. Jinfinance (on Ebay) is AAA+++ to deal with, tell him I sent you!

Dean.

[minhnguyen9113]

Hi Rachel and Dean.

I search in Ebay stores but there is no one named Jin finance.

How can I contact him.

Thanks Minh

[rachel_kinoshita]

Hi. Search for the seller jinfinance. Look for item 7560540140 for one of his focusing mounts. As Dean mentioned, you can get it without the lensboard for $119. I built a handheld 4x5 out of a Sinar rear frame and jinfinance's focusing mounts. It works great.

 

Thanks,

Rachel

[jay staton]

Minh,

 

I have a Carl Zeiss Jena Tessar f:2.7, 16.5cm helical lens if you are interested. Glass is very clean, and lens slides smooooothly with good threads and no play. Aperture is very smooth. It is presently attached to a board for my Tachihara. No shutter. I was going to use it for macro, with very fine focusing, but never got around to it.

 

It is just sitting in my closet with all my other projects for when I retire.

 

Jay

[minhnguyen9113]

Hi Jay. Thanks for your help. How much you ask for it?. I think one of my shutter will work on the lens. Let me know if I can afford

I'm happy to try it on my camera, by the way I've just finish a roll film on it today, wish it will come out good and I can show you the pictures soon. Thanks Minh

[minhnguyen9113]

Hi Jay

I have not received any email from you I'm waiting for it. The lens in the picture will work for macro only or for general purpose.

Thanks Minh

[truant]

I'd like to see a pic of that p&s 4x5 you made. Can you upload some pics and/or provide some build details?

 

thanks

 

Paul

[jay staton]

Minh,

 

Attached are a combination of lens open, and closed. I just checked, and it works for regular shooting. I am asking $215., what I paid for it. Let me know.

 

Jay

clubpgapro@aol.com<div></div>

[minhnguyen9113]

Paul

 

The camera I built from the Polaroid 900 is not 4x5 inch. It is 120 roll film panorama 6x15 cm. 1) I made a roll film holder and a film advance knob and modify the inside of the Polaroid. 2) Order a dark

plastic chamber from a plastic molding shop and fit a 105 mm , f 6.8

Spiratone lens on it. Set hyperfocus at 25 ft and took a roll film

The result you can see on the thread of Polarama 6x15. Thanks for asking

[rachel_kinoshita]

Hi Paul,

 

I'll take some pictures of it this weekend and post the link to them here. The only part I really made was the lensmount as I just took an unmodified Sinar rear frame, back and lensboard and put those together with the helical mount/lens. Along the top, I mounted three shoes and put on an old Voigtlander Rangefinder, a 4x5 Zoom finder and a new Voigtlander meter. I find that I don't use the meter much as I usually take my spotmeter with me, so I may replace that with a shoe mounted level.

 

I have to admit, I'm not very skilled with tools, so the lensmounts are somewhat crude, but they're functional.

 

Thanks,

Rachel

[truant]

cool

Thanks Rachel - Thank you for the info too Minh

 

cheers

Paul

[rachel_kinoshita]

Hi Paul,<br><br>

 

Okay, I took some quick snaps of the camera and posted them here:<br><br>

 

<a href=

http://www.photo.net/photodb/folder?folder_id=543462>http://www.photo.net/photodb/folder?folder_id=543462</a>

<br><br>

One thing I forgot to mention in my previous post. I used a Really Right Stuff L Bracket mounted to an aluminum plate I fashioned for the base. On the L bracket, I mounted a Linhof Grip. I had planned on attaching the grip to the small RRS clamp, but after assembling everything, I found it placed the grip too far away from the center of gravity. So, in the end, I attached the grip directly to the L bracket.<br><br>

The lens in the picture is a 90mm f8. I also have lensmount with a 65mm f4.5 on it. I may try to build a mount for something longer, maybe a 120 or 135mm lens.<br><br>

The nice thing about the Sinar back is that you can easily swap from horizontal to vertical, plus it's an international back, so using roll film holders and Grafmatic backs is a piece of cake.<br><br>

Thanks,<br>

Rachel

[truant]

Hey Rachel

Thanks for the photos. That is a very cool camera and I think I may attempt to fashion one for myself. One question though. How did you figure out how far out to position the lens in the lens mount. Actually - another question - what is the lens mount made of?

 

thanks again

cheers

Paul

[rachel_kinoshita]

Hi Paul,

 

At first I thought I would measure everything precisely to get infinity focus just right. However, I found it easier to just mock everything up and match infinity focus on the helical device with the groundglass. Once that was done, I simply glued the lens cone together and everything worked out great.

 

I made the lens cone out of parts I found at my local hardware store. As I mentioned, I don't have any special tools or for that matter, any skills at using tools so I chose the material I thought would be the easiest to work with, plastic. Looking in the plumbing section, I found some ABS plastic connectors and end caps that I thought could fit together to make a reasonable lens cone. With a little drilling, shaping, sanding and gluing I had my finished product. It won't win any awards for design or aesthetics, but it works.

 

Thanks,

Rachel

[murrayatuptowngallery]

Minh,

 

How do you get a 15 cm dimension in the back of a 900? Do you remove the old 'film gate'/opening frame? I measured a 95B, which I thought had the same back as 900 and it's something like 77 mm high by 104-105 mm wide.

 

Thanks

 

Murray

[murrayatuptowngallery]

Sorry, Rachel, I disagree. I'm always impressed with your camera constructions/assemblages.