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   » Reverse Scan vs Foreward Scan on Red Readers on Older Tracks

   
Author Topic: Reverse Scan vs Foreward Scan on Red Readers on Older Tracks
Bill Enos
Film God

Posts: 2081
From: Richmond, Virginia, USA
Registered: Apr 2000


 - posted 01-11-2006 08:15 PM      Profile for Bill Enos   Email Bill Enos   Send New Private Message       Edit/Delete Post 
With regard to problems with sound on older films, is red light not as good either way or is reverse scan worse than foreward??
I looked at other posts covering red light on old prints but didn't notice this mentioned, or maybe I missed it.

 |  IP: Logged

Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99


 - posted 01-11-2006 09:35 PM      Profile for Mark Gulbrandsen   Email Mark Gulbrandsen   Send New Private Message       Edit/Delete Post 
Reverse scam is clearly the winner in spite of the lower signal to noise ratio that the red array affords. You still have far lower IM and harmonic distortion, almost zero crosstalk, and things are far more stable over the long term. Need better S/N ratio just slap in an IR LED array. Thats one good advantage of the BACP reader with their user interchangable led heads.

Mark

 |  IP: Logged

Stephen Furley
Film God

Posts: 3059
From: Coulsdon, Croydon, England
Registered: May 2002


 - posted 01-12-2006 02:32 AM      Profile for Stephen Furley   Email Stephen Furley   Send New Private Message       Edit/Delete Post 
Given that reverse scan has been around for many years, long before red readers, and its advantages seem to be just about universally recognised, why did it not become standard long ago on new machines?

 |  IP: Logged

Marin Zorica
Jedi Master Film Handler

Posts: 671
From: Biograd na Moru, Croatia
Registered: May 2003


 - posted 01-12-2006 06:59 AM      Profile for Marin Zorica   Email Marin Zorica   Send New Private Message       Edit/Delete Post 
Maybee because today when you buy new machine, the is 98% that you buy DOLBY DIGITAL, DTS or SDDS. And then analogue is only for backup, so maybe because of that analogue is little backwards. But front scan system do work werry well also!

 |  IP: Logged

Louis Bornwasser
Film God

Posts: 4441
From: prospect ky usa
Registered: Mar 2005


 - posted 01-12-2006 07:49 AM      Profile for Louis Bornwasser   Author's Homepage   Email Louis Bornwasser   Send New Private Message       Edit/Delete Post 
In fact one of the old Western Electric soundheads was reverse scan, long before Century tried it and gave it a bad name. (Lonny Jennings modified several reverse scan Century's and got wonderful results using a BYS bulb (9 volt, vertical).

It is hard to believe (now with many changes happening fast and stupidly) but this industry was a very cautious place in the 1940 to 1985 era. It was felt, then, that optical was bad and that magnetic was good. No Dolby and no digital. So, "good enough" was the operable phrase. Louis

 |  IP: Logged

Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99


 - posted 01-12-2006 08:51 AM      Profile for Mark Gulbrandsen   Email Mark Gulbrandsen   Send New Private Message       Edit/Delete Post 
quote: Louis Bornwasser
In fact one of the old Western Electric soundheads was reverse scan, long before Century tried it and gave it a bad name.
Known as the TA-7400. I have one out in the garage someplace. Aside from having reverse scam it also utilizes a 3450 rpm drive motor. The slit in it is fully adjustable in height, width, and has a neato adjuster for azimuth.

Old audio equipment dealers need not call me on buying this one.... its priced so high that you don't even want to know [Big Grin] .

Mark

 |  IP: Logged

Bob Koch
Expert Film Handler

Posts: 183
From: williams ca
Registered: Nov 2001


 - posted 01-12-2006 02:34 PM      Profile for Bob Koch   Email Bob Koch   Send New Private Message       Edit/Delete Post 
The soundhead{TA 7400 which Mark has is very rare indeed. In 1935-8 Wetern Electric brought out Mirrophonic sound systems. The ones I remember most were the 3m- 86 systems. 3MA86 had the 207-08 reproducer, 3MF86 had that miserable soundhead with no sprocket;209-211,and the 3MG system which had the TA7400 reproducer which Mark has. Were`nt many because the price of the 7400 was so damn much more money that the exhibitors would`nt buy it. They have from that day to this, remained constant in their revulsion at spending any money in the projection room.

 |  IP: Logged

John Eickhof
Jedi Master Film Handler

Posts: 588
From: Wendell, ID USA
Registered: Jan 2000


 - posted 01-12-2006 02:46 PM      Profile for John Eickhof   Author's Homepage   Email John Eickhof   Send New Private Message       Edit/Delete Post 
Hi Bob and Mark! I have a real nice 7400 too! It was well ahead of it's time!! The century was pretty decent but most techs didn't know how to really adjust it! Thus there were constant problems with distortion and lower signal-noise! I'll take ANY modern reverse scan over the forward scan today!!!

 |  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.