70mm 8-Perf ?

[Jim Cassedy]

I've got this 70mm footage counter/synchronizer sitting in my booth.
It's in great shape, but the problem is that it's for 70mm 8-perf film,
which makes it useless for regular 70mm (except for counting feet)
I'm sure someone here (ie: Mark G or Steve G) can tell me what
film process used 70mm 8perf? (and was it horizontal or vertical?)
70mm8Perf_1.jpg

70mm8perf_2.jpg

[Scotty Wright]

Iwerks is the company that I know of had horizontal 8perf 65mm camera and projector solution. Mostly theme park rides I thought.

Coincidentally, Brady Corbet (director of The Brutalist) mentioned in an interview the other day he plans to shoot his next movie on 8perf 65mm.

[Steve Guttag]

It was vertical. 8/70 is the ecno-Imax. Same ratio image. Ballantyne's "Mega-Systems" and Kinoton's MP75E could support it. There was a Linear Loop machine that supported it too.

There were lens lines from the ISCO and Schneider that supported the format too. The MP75E was cool in that it supported 4/35, 5/70, and 8/70. So, one machine could support large format as well as standard cinema fare.

[Paul H. Rayton]

I have a brief clip of some 8-perf 70mm show. Don't know the name of the show (some kind of nature film), but it had been part of something shown on one of the Ballantyne systems. Like Steve says, 8-perf was the poor-man's Imax.

I don't have that original 8-perf scene scanned yet, but I do have a recent scan of the following film demo strip, which was made about 20 years ago by the late lab company Imagica. It shows the same image in actual-size copies of 35mm 4-perf and 8-perf (i.e. VistaVision), and then several 70mm formats, including 5-perf, 8-perf, and 15-perf (Imax). That strip (printed on 70mm stock) is reproduced below. I'm not real happy with the resultant image quality I got from the scan, but you can get a bit of an idea of the image sizes relative to each other, since it's the same view in every image:

Imagica 70mm 600 dpi-adj, r-75.jpg

There is also a similar kind of demonstration strip created by the late CFI lab, with a similar size comparison, using a different image. The CFI strip was a bit more inclusive, as it included also a 70mm @ 10 perf pulldown. When I get a chance, I'll scan that one and add it in here.

[Phillip Grace]

Hi Jim.

It is an Iwerks 8-perf synchronizer. The image area is the 8P frame - vertical pull-down - on Paul Rayton's Imagica film strip shown above. We ran a short season of "The Lion King" in that format some years ago, on a Kinoton MP75E as it happened. That was the only time it was ever used for 8/70. There was a DTS timecode along one edge of the print, and a DTS-6D Special Venue player for the sound.

Your double gang synchronizer may have been built for negative matching, in which case the pad rollers for one sprocket may only be wide enough for 65mm film. (Something which surprised me a while ago when I went to use one). The sprockets themselves are identical of course.

To make this unit useful for 5/70mm make up a short loop of old 5-perf print or blank stock with frame lines clearly marked on it and clamp it onto the back sprocket. It is easy to read across to the front sprocket to locate the frame lines.

[Mark Gulbrandsen]

The linear loop I worked on was this one south of Salt Lake City at the Dinosaur Museum. The system ran there for about 5 years and was then replaced by the dual 15/70 3-D system at the right. That system lasted about 7 years, and was replaced by a side by side 3-D Digital system using Christie SB projectors.

[Jim Cassedy]

Great photos, Mark. Thanks for posting!

[Thomas Piccione]

The linear loop I worked on was this one south of Salt Lake City at the Dinosaur Museum. The system ran there for about 5 years and was then replaced by the dual 15/70 3-D system at the right. That system lasted about 7 years, and was replaced by a side by side 3-D Digital system using Christie SB projectors.

I've seen photos of and heard about the linear loop machine before, how exactly did it work? Are the teeth on the back of the gate stationary and used as registration?

[Tony Bandiera Jr]

Back to the synchronizer: If you want to make it easy to use, there is a way but it will be tedious. You will need Two miniature files, one triangular, one narrow and flat. Plus a Sharpie or paint in whatever color you want.

Between each set of the frame slots/cuts already on the sprockets, cut a new slot with the triangle file between teeth 5 and 6. Deburr it flat and smooth with the flat file. Color in those new slots with paint or a Sharpie of your choice in colors. This will give you easy reference points for framelines.

If you want to get fancy you could also make a new "ring" label for the outside sprocket to give you two (or three) sets of frame numbers. If it were me, I'd mark them with the top number as the 5 perf and the bottom as 8 perf. And to REALLY be fancy, add a third set of numbers for 15 perf. Offset the numbers midway by 2.5, 4, and 7.5 vallys between tooth sets respectively.

[Paul H. Rayton]

Below is a scan of the one bit of 10-perf 70mm film that I have. I must apologize for the image: it is absolutely the worst possible image to use for such [scanning] purposes, but it's the only sample available here. It's kind of a jungle scene, with a pair of primates (gorillas?) in the lower foreground. But the lighting is terrible, mostly all dark but with a sprinkling of very bright points where the sunlight peeks into the jungle. I obtained the most reasonable image I could get from this scanner, keeping in mind that, for these purposes, I needed to make sure the frame size is apparent, trying to show the perforations along the edge while trying to keep a semblance of the original photographic image. Even doing so, the perfs are still practically invisible in this rendition. It's definitely an awkward compromise, but it does show a piece of 70mm motion picture film using the 10-perf pulldown. (This is the piece I referenced in my initial post 2 days ago, which I said was 8-perf. Oops! Since I never personally projected it, I'd never actually counted the perfs per frame. Today doing the scan, I could see it's really 10-perf, not 8-perf, so it wouldn't precisely count off frames in Jim's synchronizer.) The Kodak date code along the edge of this print stock shows as 1995. If anybody has any idea what show this was from, I'd be pleased to learn it. The movie "Gorillas in the Mist" was from 1988; this one may be some kind of opportunistic follow-up, playing to the interest revved up by the earlier big-name movie...

8-perf, 'photo', at 600dpi-adj-r25.jpg

Here's a single frame of the above strip, tweaked to really show the perforations, and ignoring any attempt to show the image itself. Note the pin registration holes, every 5 perfs.

10-perf, 'photo', at 600dpi, single frame.jpg

[Ryan Gallagher]

I've had a ebay saved search for a while... the 5perf ones seem to be diamonds in the dust already, wonder how many of these 8 perf ones were ever produced!

You could probably change out that indexing label pretty easily, maybe even the wheel that it indexes to if you are inclined to make a new one... would hate to file/modify in any way that can't be reversed though?

[Tony Bandiera Jr]

I've had a ebay saved search for a while... the 5perf ones seem to be diamonds in the dust already, wonder how many of these 8 perf ones were ever produced!

You could probably change out that indexing label pretty easily, maybe even the wheel that it indexes to if you are inclined to make a new one... would hate to file/modify in any way that can't be reversed though?

Ryan, the mods I suggested will not harm it (or the film) in any way. Since AFAIK no one has ever made a 70mm (or 35mm for VistaVision) syncro that will be usable for all formats, the mods would IMHO make it even more rare and valuable.

I'd say the 8 perf models are even more rare than 5 perf as there were a lot more 70mm screens than large format Imax at one time.

[Ryan Gallagher]

Ryan, the mods I suggested will not harm it (or the film) in any way. Since AFAIK no one has ever made a 70mm (or 35mm for VistaVision) syncro that will be usable for all formats, the mods would IMHO make it even more rare and valuable.

I'd say the 8 perf models are even more rare than 5 perf as there were a lot more 70mm screens than large format Imax at one time.

For sure. Just saying those file-lines are only there as a visual reference, they are not part of how it actually indexes when you activate the lever, which would be my real goal of modding if I was trying to make a functional 5P one. Some kind of updated frame line between the sprockets would be a secondary bonus, or a stop gap if you can get by with only the free-wheel mode.

[Jim Cassedy]

I actually liked Tony's idea. It's a fairly simple modification. It would be nice to verify
framing. The only thing that I really use it for now is to measure feet to back-time
the curtain cue.

[Randy Stankey]

Too bad you couldn't put in a rotary encoder or even just an IR sensor to count clicks as the sprockets turn. Then you just make a divide-by-n counter and a digital display. Build in a control so that you can change "n" to the number of sprockets per frame. You'd be able to use it on any format of film that people can throw at you.

The electronic parts should be obtainable from the usual suspects. The only part I can't really figure out is how to put on the encoder/sensor. I'd have to see the device in order to figure it out but I'm sure that there are others who could do it just as well as I could...even better.