Film-Tech Forum ARCHIVE: Kinoton lens holders for silent film

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Posted by Stephen Furley (Member # 1277) on 12-27-2004, 07:34 AM:

Does ,or did, kinoton make lens holders for the FP-20 with the optical axis correctly positioned for silent film?

Posted by Steve Guttag (Member # 268) on 12-27-2004, 12:07 PM:

Stephen,

Yes, you have two options. You may use the 101.6mm lens holders and install a PC-Cine adapter to offset the lens (part number 8990 240 29040)

Or you can use your standard 70.6mm lens holders and use a lens with a 62.5mm OD (most in the USA don't realize that Schneider and ISCO lenses can be had with either 62.5 or 70.6mm OD since all US maches are for 70.6 or 101.6mm) and then order a intermediate ring number 0070 410 000110 which will take the 62.5 ID and make it a 70.6mm OD with the offset.

Steve

Posted by Peter Hall (Member # 695) on 12-29-2004, 07:39 AM:

Hi Stephen

We use std lens barrels and concentric adaptors which we make ourselves. We primarily use these for S35 installs however full frame is the same thing. On a FP20, (or FP30) you'll also need to cut away the heat shield, possibly trim the white runners and certainly realign the lamphouse. Is it a site I know ??

Hope things are good and that you had a good Xmas

Cheers

Posted by Phillip Grace (Member # 2262) on 12-29-2004, 06:08 PM:

Hello Stephen,

At this theatre we have FP30E and FP38E machines, all of which will accept the 101.6mm diameter lens holder. For full aperture silent we are using Isco PC adaptors which have more than enough movement and are quite simple to adjust. A useful feature of this arrangement is that it allows the operator to centre an image which is not correctly placed on the film, which is sometimes the case with archival prints due to shrinkage of the originals.

Cheers.
Phil.

Posted by Stephen Furley (Member # 1277) on 12-30-2004, 03:27 AM:

Peter,

It's a small place in the South of France. I know the chief there, but I've not been there. Hope to get a visit sometme.

Do you mean you're using 70.6mm holders with small lenses? That was an idea I had last year, but I don't know how readly available suitable lenses are. Or do you mean you're using 101.6mm holders with standard lenses. Can the FP-20 even take 101.6mm holders? I've never seen one. I don't know what lenses they need, but I've seen some pictures of the auditorium, and it's qute long and narrow, so they'll be fairly long FL. They want to run a short season of silents nwxt summer.

I'm still looking for some 2k spools for my own FP-20, I wasn't able to get to you this year, so I had to borrow some. I only use the thing about once each year, so I've got a bit of time before the next time I need them.

Posted by Steve Guttag (Member # 268) on 12-30-2004, 09:04 AM:

The Kinoton 101.6mm lens holder looks like this:

It will fit the FP-20 just fine. You will need a PC-Cine adapter of some sort though to get a standard lens to fit and to allow for the offset for silent. ISCO's part number is 720.00

You can also use 62.5mm diameter lenses with the eccentric intermediate tube as listed in my earlier post. 62.5mm lenses are available from ISCO and Schneider in most of the sizes up to 95mm For ISCO's part numbers on their RED lenses change the last two digits from .33 to .32 for the 62.5mm diameter version.

For instance, if you want an 85mm lens...the normal 70.6mm diameter is 738.33. The 62.5mm diameter lens is 738.32.

Steve

Posted by Stephen Furley (Member # 1277) on 02-10-2005, 07:06 AM:

I've got the figures, and done the calculations; focal length comes out at 88mm. Call it 90mm, and they'll have to bring the masking in slightly.

Are ISCO or Schneider better at this length? would you recommend going for 62.5 lenses in 70.6 holders, or 70.6 lenses in 101.6 holders? (Where on Earth do they get these sizes from?) Any rough idea of pricing for lenses, holders and off-centre mounts? Anybody know any good dealers in France?

They now have three projectors, but only need to equip two of them.

Posted by Mark Gulbrandsen (Member # 72) on 02-10-2005, 07:42 AM:

I would highly recomend that one actually check the offset of any lens offset collar you buy from Kinoton to be sure its correct. We recently discovered that Kinoton can't even properly machine the offset of a DP-70 lens adaptor any more.

Steve,

That 101mm lens holder sure looks VERY tacky... literally! Tack welds.... what is happenning over in Kinoton land, It would appear that they have lost the ability to make real quality castings any more... Aside fomr looking tacky t
those welds WILL definately cause the alumnium to loose its temper at and around those spots and it can distort easily. They definately took the short cut on those and it looks like much of the famed Kinoton quality has headed out the door.

Mark @ CLACO

Posted by Steve Guttag (Member # 268) on 02-10-2005, 07:57 PM:

Mark,

The 101.6mm lens holders have always been steel, not aluminum. Yes, they are quite heavy. They have ALWAYS been welded like that...the difference on an older one was that the outside welds were ground smooth before painting (the inside welds were left "natural".

The only functional difference between the current production 101.6mm lens holders and the old ones is that the old ones had a light shield to minimize light scatter from the projector.

As to 101.6mm...that is a easy size to figure out...equals 4" exactly. It is 70.6mm that is the odd one...it is 2-25/32 in "English" measure...it doesn't work for anyone! The SMPTE Journal a couple of months ago had an article by Glenn Berggren on the origin of cinema lenses that was quite interesting.

As for the Silent thing...I use 101.6mm lens holders and then offset with PC-Cine adapters...but I normally have all my lenses in 101.6mm holders to minimize keystone across the varied formats (typcially 5 or so per projector for my installations).

If you have toed-in your projectors to use the 70.6mm lens holders, you should be able to get away with 62.5mm lenses and the offset tube. It isn't my first choice but it certainly is the least expensive. I'm afraid I can't help you with dealers in France.

As to which lens is better in your focal range. I think pros and cons could be said of both Schneider and ISCO but both are better than anything else. Schneider has the Cinelux-Premier that will let you stop down the lens to f/4 so you may achieve a better light balance with your other formats. ISCO's Ultra-Star PLUS may be stopped down to f/2.7 (recommended on Silent since its aperture is so much larger and the screen image is typcially so much smaller).

Steve