Page 1 of 2 12 LastLast
Results 1 to 10 of 19

Thread: Building a Sinar Handy from non-Sinar parts

  1. #1

    Join Date
    Jun 2002
    Posts
    9,476

    Building a Sinar Handy from non-Sinar parts

    I've always been intrigued by the idea of assembling a helical focus wide angle camera like a Sinar Handy from off the shelf parts. I know the right thing to do is to find a vintage used lens already in a Handy cone and focusing mount, which would simply fit onto the front of a 4x5 format frame and you'd be good to go except for a tripod mount and a shoe for the viewfinder.

    So... how would you add a shoe mount and a proper tripod hole to a Sinar format frame? What is the slickest way?

    Short of finding an OEM Sinar Handy Cone/Helical/Lens, has anyone used those new cheap Chineses focusing helicals they are selling on eBay? I would like to avoid messing around and hoping for the best with regards to focal flanges distances and vignetting, so are there any lens combinations that you know would work with a flat lenboard (no cone) and not vignette too badly? (It seems like you could stick a 65mm onto one of those, stick it on a Sinar board and be ready to go, but I don't wannabe to be the first to try it...)

  2. #2
    Whatever David A. Goldfarb's Avatar
    Join Date
    Mar 2000
    Location
    Honolulu, Hawai'i
    Posts
    4,658

    Re: Building a Sinar Handy from non-Sinar parts

    Now I know I've seen that shoe mount for an accessory finder (that looked very much like the finder on a Graphic) in some old Sinar catalogue. It may have even used the keyhole slot.

  3. #3

    Join Date
    Feb 2005
    Location
    Houston, TX
    Posts
    139

    Re: Building a Sinar Handy from non-Sinar parts

    Frank... we can supply you with both the high quality Helical Focus Mount and Viewfinder for your project, as well as the accessory shoe to mount the viewfinder if you need. We could also make you a custom lensboard and any spacers you might require for that matter... http://www.fotomancamera.com

  4. #4

    Join Date
    Jun 2005
    Posts
    2,480

    Re: Building a Sinar Handy from non-Sinar parts

    Quote Originally Posted by Frank Petronio View Post
    I've always been intrigued by the idea of assembling a helical focus wide angle camera like a Sinar Handy from off the shelf parts. I know the right thing to do is to find a vintage used lens already in a Handy cone and focusing mount, which would simply fit onto the front of a 4x5 format frame and you'd be good to go except for a tripod mount and a shoe for the viewfinder.
    If I understand you well - and I'm not sure of it - the biggest hurdle you face is to make sure your lens with the helical mount is plan parallel to the film. Not easy and of uttermost importance with wide angles.

  5. #5

    Join Date
    Jun 2002
    Posts
    9,476

    Re: Building a Sinar Handy from non-Sinar parts

    I would expect the helicals to be relatively parallel if everything is mounted properly. I think the big problem is to get the right distance between the lens and the film so that it doesn't vignette and so that the focus throw is appropriate (infinity to 3 feet or so) with the helical mount. That's why I am looking for people who have already done this and know which lens works with which mount.

    The Fotoman option is pretty appealling actually, in fact maybe there is a new product for them in this (a ready to go camera using people's existing Sinar, Toyo, Linhof, or Arca -- any 'system" camera -- frames and backs?)

    I mean I'd drop a couple of hundred on a mount and Sinar sized lensboard knowing that a 90/6.8 Grandagon (or whatever) will drop in and be good to go...
    Last edited by Frank Petronio; 5-Oct-2006 at 11:41.

  6. #6

    Join Date
    Jun 2005
    Posts
    2,480

    Re: Building a Sinar Handy from non-Sinar parts

    It's not that the helical mount would wobble - it's rather a question of how you want to make the whole lens board with the helical mount to get an to maintain the precise plan parallel position.

  7. #7

    Join Date
    May 2004
    Location
    Munich
    Posts
    77

    Re: Building a Sinar Handy from non-Sinar parts

    There should be somebody who could tell you the minimal length and the inner diameter of a Pentax 6x7 helicoid extension tube. I'd be surprised if the rear lens of the shorter and slower Grandagon and Super Angulon types couldn't be moved within the tube while focusing - and without getting the picture vignetted.
    Building my own 4 x5 wide angle camera is still a project. But since I have already built two smaller cameras with helical tubes, I don't think it should be too difficult. One of them is based on an Ercona body and provides both 6x8/ 6x6; the other one is a 24x72 "panoramic" camera for which I used a Meopta copying body ("Reprokassette" in German). The lens is a Koni Omega 58mm which got a Minolta bayonet so that I can use it with either camera. (One helical tubes served as a telescope focouser before; the other one I hacked from a Vivitar tele converter.

    Uli
    Last edited by Uli Mayer; 5-Oct-2006 at 13:51.

  8. #8

    Join Date
    Feb 2005
    Location
    Houston, TX
    Posts
    139

    Re: Building a Sinar Handy from non-Sinar parts

    Determining the correct distance at which the lens should be placed, and maintaining perfect parrallelism are the keys to building any camera. Using the 90/6.8 Grandagon example, the distance between the face of the HFM to the film must be exactly 94mm. Subtracting the thickness of the HFM and both standards as well as the set back from the rear standard to the film plane will determine the remaining distance needed to be "filled" with a spacer that would connect the two standards... essentially a rigid bellows. The viewfinder and tripod mounts would be added to the spacer itself. Vignetting should not be a problem at all, assuming you select a lens that covers 4x5. Neeedless to say, the spacer would have to mate to the standards in such a manner that prevents light leakage, which would likely require machining of the standards to provide a method of affixing the spacer.

    My Toyo 4x5 has standards that are around 12mm in thickness plus another 6mm or so back to the film plane (not measured). Using the Fotoman HFM at 17.4mm in thickness would result in the need for a spacer 46.6mm thick... 94 -(12+12+6+17.4).

    Aternatively, the required spacer length could be added between the helical and the front standard. This is how the Sinar Handy and Fotoman 45PS cameras are designed, and the "spacer" becomes a "cone". It needn't be conical however, thought additional weight will be incurred by a flat design.

    Another way to look at it would be to calculate the stacked thickness first and then try to find a lens with a FFD that matches. This would eliminate the need for any spacer mechanism. Using the prior 90 Grandagon-Toyo Standards example the stack dimension is 47.4mm. In this example you could use a 47XL on a 12mm recessed lensboard (59.1 FFD -47.4). The final .3mm being adjusted within the HFM itself when calibrating focus for infinity.

  9. #9

    Join Date
    May 2004
    Location
    Munich
    Posts
    77

    Re: Building a Sinar Handy from non-Sinar parts

    Calculation of camera depth may wisely be based on the fact that effective focal length (and consequently flange focal distance) of lenses can vary by +/- 1% , as older data sheets state. Thus one should't start with a FFD of 94mm ( by taking the example given above) but with a FFD of ca. 93mm. This is to make sure that the final camera body will not get too deep for reaching "infinity"-focus.

    I don't see much advantage in using a helical mount with an already given "infinity"-position and a marked distance scale. Instead of "harmonizing" everything - by resorting to spacers - so that the scale can be used, one can easily take a plain mount and mark positions after the whole apparatus has been assembled. "Infinity" may then be with the focuser one or more millimeters drawn but that's much better than having to start all over again. It happened!
    Last edited by Uli Mayer; 6-Oct-2006 at 01:59.

  10. #10

    Join Date
    Jun 2005
    Posts
    2,480

    Re: Building a Sinar Handy from non-Sinar parts

    Quote Originally Posted by Uli Mayer View Post
    I don't see much advantage in using a helical mount with an already given "infinity"-position and a marked distance scale. Instead of "harmonizing" everything - by resorting to spacers - so that the scale can be used, one can easily take a plain mount and mark positions after the whole apparatus has been assembled. "Infinity" may then be with the focuser one or more millimeters drawn but that's much better than having to start all over again. It happened!
    The great disadvantage of your later metod is that you cannot focus at infinity automatically, just turning the HFM to its end position - you must look at your infinity mark first. "Harmonizing everything" - that's where you come to my original question - how do you want to put "everything" in the exact distance and the plan parallel position? Unless you have a clear answer to this question you cannot build anything precise.

Similar Threads

  1. Making a Sinar Handy type camera
    By Frank Petronio in forum Cameras & Camera Accessories
    Replies: 13
    Last Post: 8-May-2010, 07:46
  2. Sinar Norma parts
    By Paul Feyling in forum Gear
    Replies: 5
    Last Post: 20-Feb-2006, 06:43
  3. Sinar P Replacement Parts
    By Ron Marshall in forum Cameras & Camera Accessories
    Replies: 1
    Last Post: 28-Jan-2006, 15:10
  4. Sinar Handy 47/5.6 cover 6x12?
    By Frank Petronio in forum Lenses & Lens Accessories
    Replies: 13
    Last Post: 25-Apr-2004, 15:36
  5. Sinar Parts Interchange
    By Fender in forum Cameras & Camera Accessories
    Replies: 1
    Last Post: 26-Feb-2001, 18:56

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •