Triple adapter - police accessory

meldert · Posted: Sun Mar 25, 2012 9:26 pm Post subject: Triple adapter - police accessory

Hi!
I have a Triple adapter made by Wilhelm Nass in Hannover, for three exposures 4x6cm on sheet film, original back and some sheet film holders. This outfit was used by the Swedish Police but was originally created for the German Police.
I have tried it once but with a discouraging result. I think I am missing some info about how to use it. Since the film focus plane is a few millimetres way back in the camera it doesn't focus right the usual way. Does anyone know what else is needed?

Thomas Meldert
Stockholm, Sweden

DPurdy · Posted: Mon Mar 26, 2012 4:31 am Post subject:

I have never seen nor heard of the 645 police back but there is the regular sheet film back that has holders. On the holders there is a "key". Once you put the film holder in the back and remove the dark slide you must turn the key and a spring will push the film up to the film gate inside the camera. that gives very flat film at the proper distance from the lens.
Check to see if your police holders have a little key on them on the back side.

meldert · Posted: Mon Mar 26, 2012 4:58 am Post subject: Triple adapter - police accessory

I know the ordinary sheet film back but this is something different. It is more like a large format cassette mounted on a modified back. The film plane is in fact a few milimetres way back from the original film plane.

Please respond only if you have some information about this item. I would like to use it with good results. My first attempt was a disaster =)

Thomas Meldert

JanBoettcher · Posted: Mon Mar 26, 2012 10:24 pm Post subject:

The complete set includes a negative lens to be mounted within the camera just behind the taking lens.

The lens' frame is like the film stage for Rolleikin, followed by a "funnel" towards the taking lens, holding the corrective element. The parts (except for the glass) are painted black

This negative lens / corrective element is needed to make up for the increased lens-film (plate) distance.

a) Don't ask, where to get one ;-) I've been to Hannover to talk to Herr Nass (probably "junior") a few years ago (too late, they didn't have any nor a clue) ... maybe you should raid all cellars/closets/attics of all Swedish police stations and older police men's homes.

b) Don't ask for the precise specification of the lens (I wonder wehre I have mine (don't ask how&where I got it) ;-) Maybe one could take a mechnical measurement (how much the lens-film distance is increased) and calculate the lens' needed strength (and get it via a local optician and build the "funnel" from scratch).

c) Just a wild idea: In order to "enlarge" the projected picture of the Rollei P95.0 projection device there were single Rolleinar lenses with "-" lenses

sooo maybe one could use one of these or just adopt the idea (take a regular Rolleiflex filter-mount, a properly calculated negative lens from your local optician and forget about making that "funnel").

JanBoettcher · Posted: Mon Apr 09, 2012 7:17 am Post subject:

Check here http://www.westlicht-auction.com/index.php?id=246546&acat=246546&_ssl=off

lot 393 last pic ...