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Author Topic: Dolby Digital Drop-out Adjustment Markus Lemm Expert Film Handler Posts: 113 From: Ottawa, Ontario, Canada Registered: Nov 2005 posted 04-29-2010 04:49 PM                        I have a DA-20 that drops out at some splices, pre-existing or our splices. Using the DRAS I see that when it drops it has more than 4 consecutive unreadable data blocks. Is there a way to change this value to 5 or 6, maybe with a firmware update?  |  IP: Logged Monte L Fullmer Film God Posts: 8367 From: Nampa, Idaho, USA Registered: Nov 2004 posted 04-29-2010 07:53 PM                     Don't use opaque tape, if you're doing this, or get the narrower width, 3/4" "Splicemark" splicing tape that won't be picked up by the reader since this narrower tape will not block out an entire, 4 sprocket block of the SRD track. This goes for all SR-D readers - both basement and penthouse readers. -Monte  |  IP: Logged Joe Redifer You need a beating today Posts: 12859 From: Denver, Colorado Registered: May 99 posted 04-29-2010 11:17 PM                        Is it dropping out at the reel changes? Even with solid yellow opaque tape (was that redundant?) it should not drop out at a reel splice if your equipment is in a good state of repair. But splices between trailers and in the middle of the reel you need to be really careful on how you make the splice, making sure your splicer is adjusted and not chopping things up. And no, there is no way to increase the amount of unreadable blocks because it would just revert to silence if you did.  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 04-29-2010 11:23 PM                     What is your typical error rating? What brand and type of splicing tape are you using? What kind of splicer are you using, and is it TRULY in proper alignment? What model Dolby Digital reader do you have? Something is definitely wrong, as I NEVER have dropouts at splices. Most often I find it is due to lousy splices, but you could have a reader in need of adjusting, or if you have a cat699 or cat700 penthouse it might be time to change the bulb, etc.  |  IP: Logged Markus Lemm Expert Film Handler Posts: 113 From: Ottawa, Ontario, Canada Registered: Nov 2005 posted 04-30-2010 09:16 AM                        We only use the yellow opaque tape for splicing films running in DTS, the clear stuff for anything SR or SR.D. Typical error rate is about 3 to 5 on trailers and newer films, our Dolby Reader is the DSTR-20 installed about 1 year ago. Brad you are right about the splicer not being in perfect alignment. I find that I have to hold both sides of the film apart to get undamaged blocks. The splicer does need some work. My real question is since Dolby Digital is already buffering the sound for my penthouse reader by nearly 3 seconds, couldn't it just compensate by doubling up known blocks so that the sound does not drop when it gets to the damaged area?  |  IP: Logged Sean McKinnon Phenomenal Film Handler Posts: 1712 From: Peabody Massachusetts Registered: Sep 2000 posted 04-30-2010 01:22 PM                        When aligning the reader do you use a scope in addition to dras? If not you really should...  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 04-30-2010 01:58 PM                        My one-note mantra: dras is almost useless for alignment. Scope only (plus dras on-the-back-end.) Louis  |  IP: Logged Demetris Thoupis Phenomenal Film Handler Posts: 1240 From: Aradippou, Larnaca, Cyprus Registered: Apr 2001 posted 05-01-2010 04:54 AM                     The BACP penthouse usually comes factory pre-alinged and no further adjustment is needed. I would check if you have another DA20 to change the CAT 670 (video aquisition board) to check if the problem moves. Demetris  |  IP: Logged Sean McKinnon Phenomenal Film Handler Posts: 1712 From: Peabody Massachusetts Registered: Sep 2000 posted 05-01-2010 01:42 PM                        is the dstr-20 the penthouse or the basement reader i don't remember?  |  IP: Logged Joe Redifer You need a beating today Posts: 12859 From: Denver, Colorado Registered: May 99 posted 05-01-2010 02:41 PM                        Penthouse.  |  IP: Logged Sean McKinnon Phenomenal Film Handler Posts: 1712 From: Peabody Massachusetts Registered: Sep 2000 posted 05-01-2010 02:47 PM                        Then it should be factory adjusted perfectly however if something got loose in shipping or someone tried to "make it better" after install it may be out of alignment now. Using a scope is the only way to tell if it is in correct alignment and that you have an adequate video signal level.  |  IP: Logged Demetris Thoupis Phenomenal Film Handler Posts: 1240 From: Aradippou, Larnaca, Cyprus Registered: Apr 2001 posted 05-01-2010 03:15 PM                     The bacp unit actually comes with the triled indicator. Yellow for excessive , green for adequate and red for Low video level. Factory alingnent is spot on.vmaje sure you have constant tension of reader from platter. A video of the splice passing through might help us more because there is a secret adjustment. Also make sure you thread on the guidelines indicated across the chassis especially at the tensioning rollers. Demetris  |  IP: Logged Joe Redifer You need a beating today Posts: 12859 From: Denver, Colorado Registered: May 99 posted 05-01-2010 03:28 PM                        The Dolby Cat 702 has that same indicator with the same colors. I received a replacement LED for one of my DSTR-20's and it is almost always orange/yellow (though sometimes green when film is running). It can't be turned down enough. Plays fine, but I'm sure someday the LED will wear down enough to the point where it is perfect.  |  IP: Logged Sam D. Chavez Film God Posts: 2153 From: Martinez, CA USA Registered: Aug 2003 posted 05-01-2010 06:50 PM                       There is a LED current adjustment on the DSTR inside the CCD cover. BACP actually came up with this idea and later Dolby modified their board to do the same Tri-color LED.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-01-2010 07:17 PM                     All current basement readers feature the red/green LED thing too. Also, the CP650 can read out the video level on either its front panel (stupidly, it is in the "installers menu" rather than in the normal menu) or via the set up software where some engineer was thinkin'. The display is HUGE so it is easy to read at a distance. As for Dras...I suspect, on a CP500 or DA20 system, I could get the reader alignment, including video level just about perfect using only Dras..it would certainly be harder as you are looking at results. On a CP650, I could also probably do it though it would be much harder since I wouldn't have the LEDs on the "corners found" to aid in getting things close, particularly with the LED positioning. Steve  |  IP: Logged

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