Film-Tech Cinema Systems
Film-Tech Forum ARCHIVE


  
my profile | my password | search | faq & rules | forum home
  next oldest topic   next newest topic
» Film-Tech Forum ARCHIVE   » Operations   » Film Handlers' Forum   » Recording pix and sound separately - and back

   
Author Topic: Recording pix and sound separately - and back
John Walsh
Film God

Posts: 2490
From: Connecticut, USA, Earth, Milky Way
Registered: Oct 1999


 - posted 05-04-2003 03:23 PM      Profile for John Walsh   Email John Walsh   Send New Private Message       Edit/Delete Post 
First, some background.... We recently bought two large format Kinoton MK75's: projectors allowing us to run 4/35, 5/70 and 8/70 prints. Apparently, we have the only two in the US. These auditoriums have 70mm DTS readers, biphase generators and (for audio) DAT tape (and hard drive) recorders. We were glad to get them, because now we can run the standard large format educational stuff during the day (if I had to sit through 'Mysteries of Egypt' one more time, I'd barf) but then run regular product at night. Simply put, this allows us to make more money in those auditoriums. We'd like to book regular 70mm prints there for, say, a 70mm festival to get even more use.

The problem is, we do not have a 70mm mag head for these projectors. We could probably get them, but I know it would take a long time. I don't think one was actually designed for it yet, and they would be very expensive. There just aren't very many of them around. Even so, I probably couldn't justify the cost for the few times we'd use it.

So, I'm wondering if we could bring a 70mm mag print to one of our 'regular' 70mm auditoriums. Put the print together, put a biphase generator on the projector, run it and 'record' the mag tracks onto the DAT recorder (a DA98.) Then, bring the print to our LF auditorium and run the same print with the sound comming from the DAT. It would take some work, but still much cheaper than the cost of the two mag readers.

Could it work... even so, would it be bogus?

 |  IP: Logged

Scott Norwood
Film God

Posts: 8146
From: Boston, MA. USA (1774.21 miles northeast of Dallas)
Registered: Jun 99


 - posted 05-04-2003 03:40 PM      Profile for Scott Norwood   Author's Homepage   Email Scott Norwood   Send New Private Message       Edit/Delete Post 
It's definitely possible, but you'd need a tape format that carries more than two tracks if you want to reproduce 70mm soundtracks properly, along with some outboard processing to decode any NR that might exist on the 70mm tracks.

You probably could do it with a DA-88 machine or 8-track reel-to-reel, although they aren't especially cheap, either. There would also be some running-time limitations. At 15ips, a 10.5" reel (2500') would run for only about half an hour. DA-88 tape runs for longer, although I don't remember the exact length.

Hopefully someone else can comment on the technicalities of synching the projectors to the tape recorder (probably using timecode generators on each).

 |  IP: Logged

Bruce Hansen
Jedi Master Film Handler

Posts: 847
From: Stone Mountain, GA, USA
Registered: Dec 1999


 - posted 05-04-2003 04:08 PM      Profile for Bruce Hansen   Email Bruce Hansen   Send New Private Message       Edit/Delete Post 
If I remember correctly a DA-88 will do 113 min. max. The problem would be getting the two units to sync up to the same place every time. Do you happen to have a mag film reader, that will sync to by-phase from an encoder on the projector? Does your projector have the mag "penthouse", but not the mag head? If so, mabe you could find a used one somewhere. Just make sure it is not worn too badly (you lose high freq. resp.).

 |  IP: Logged

Steve Kraus
Film God

Posts: 4094
From: Chicago, IL, USA
Registered: May 2000


 - posted 05-04-2003 04:25 PM      Profile for Steve Kraus     Send New Private Message       Edit/Delete Post 
What are your "regular" 70mm machines? If it was an undriven penthouse like an X-L could it not be applied somehow to your new machine?

 |  IP: Logged

Matt Hale
Expert Film Handler

Posts: 123
From: Vancouver, Canada
Registered: Dec 2002


 - posted 05-04-2003 05:02 PM      Profile for Matt Hale   Author's Homepage   Email Matt Hale   Send New Private Message       Edit/Delete Post 
DA-98s do not have a biphase input. You are going to need at the very least a biphase to word clock converter to make sure everything runs at the same speed, and optionally a biphase to timecode converter to make sure everything is running in the right place at the right speed.

But it can be done. I used to sync all manner of multi-track devices to our Simplexes, starting with biphase and converting it to whatever the particular machine accepted for sync.

 |  IP: Logged

Phil Hill
I love my cootie bug

Posts: 7595
From: Hollywood, CA USA
Registered: Mar 2000


 - posted 05-04-2003 05:12 PM      Profile for Phil Hill   Email Phil Hill       Edit/Delete Post 
Your DA-98 could be used with a DTS E-175 to convert the bi-phase tach signal to SMPTE TC for the 98.

>>> Phil

 |  IP: Logged

Steve Guttag
We forgot the crackers Gromit!!!

Posts: 12814
From: Annapolis, MD
Registered: Dec 1999


 - posted 05-04-2003 05:56 PM      Profile for Steve Guttag   Email Steve Guttag   Send New Private Message       Edit/Delete Post 
I just gave the MP-75 manual a peek...it does list a threading with Magnetic sound. Therefore, I suppose that a mag sound head (Com70) would have been an option when you ordered your projector(s).

The 70mm mag system seems to be the DP-75's maghead (complete with sprocket and goofy film pad). So, in order to upgrade your machines to magnetic capability, you may find it cheaper to find some good/used DP-75s and take the mag stuff out.

My guess is that you will need a new top-most panel with the cutouts for the magnetic stuff and that the torque motor reel drive will need to live in a penthouse...neither of which should be too expensive and definately less hassle than duping films on a case by case basis. Give Kinoton America a call...they will probably roll their eyes at first but it is probably doable with just some effort and reasonable cost, once the DP-75 head(s) can be located.

As to duping the films...what a pain. Once you have a suitable medium (regardless of type) then each film will need to be duped on a print by print basis and in the event a film breaks or gets mangled, you will need to slug the picture to keep it matched to the sound. I don't deny that it is certainly doable just more effort on an ongoing basis. Factor in the revenue on one good 70mm playdate and you would have bought your 70mm mag equipment.

There are a couple titles now available in 70mm DTS...like Lawrence of Arabia and it is likely that future reissues will have the DTS offering.

Steve

 |  IP: Logged

Larry Shaw
Expert Film Handler

Posts: 238
From: Boston, MA, USA
Registered: Mar 2000


 - posted 05-06-2003 06:29 PM      Profile for Larry Shaw   Author's Homepage   Email Larry Shaw   Send New Private Message       Edit/Delete Post 
John,

So far there are 3 MP-75E's in the US, and there is a mag upgrade kit that was installed at the Cinerama Dome. Delivery time isn't crazy, but obviously it's not "off the shelf".

 |  IP: Logged

John Walsh
Film God

Posts: 2490
From: Connecticut, USA, Earth, Milky Way
Registered: Oct 1999


 - posted 05-06-2003 08:38 PM      Profile for John Walsh   Email John Walsh   Send New Private Message       Edit/Delete Post 
Hi there, Larry!

Yes, as you might have already guessed, I'm trying to do this on the cheap! But, what at first glance seemed like something that might work, as too many problems...

I could record it from the CP200 output to have a nr decoded, but it might be to noisy... the tape won't run long enough, although we do have a biphase on the projector and a Ketchum box to drive the DA98's.

Steve (and Steve's!) idea about adapting the mag from a DP75 is interesting, since we have four of them that I know will never run 70mm again.... Thanks to everyone!

Off topic, but..

I'd like to mention that BL&S / Kinoton America hosted an excellent seminar on Kinoton projectors, (with emphasis on the PK60) a while ago. I braved those crazy Boston roads and it was well worth it. It was very through and we actually took projectors apart, made adjustments, etc. Factory reps from Germany were there for questions and told things you needed to know, even if it was something like a design flaw or other factory error .... everyone had a great time. The reps kept apologizing for their bad english, but frankly they spoke better than some of the native Americans working at some of our theaters... [Smile]

 |  IP: Logged



All times are Central (GMT -6:00)  
   Close Topic    Move Topic    Delete Topic    next oldest topic   next newest topic
 - Printer-friendly view of this topic
Hop To:



Powered by Infopop Corporation
UBB.classicTM 6.3.1.2

The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion and agrees to release the authors from any and all liability.

© 1999-2020 Film-Tech Cinema Systems, LLC. All rights reserved.