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Author Topic: Newer Red LED's Michael Schaffer "Where is the Boardwalk Hotel?" Posts: 4143 From: Boston, MA Registered: Apr 2002 posted 06-26-2003 04:40 AM                        Manny: In the setup manuals for the digital processors, there is a section where the error rate display is explained and the actual number of errors which are reflected by the numbers on the display is listed.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 06-26-2003 07:15 AM                     To the best of my knowledge, Dolby single-sources the visible red LEDs. BACP/USL I believe have a similar LED as an alternative but I have yet to use it. As to the "blips"...they are not a function of the higher error rate, persay. They are just uncorrectable errors. If you were to look at the Cat. 673 card's red LED...(with the cover off on a DA-20) you will see it flash anytime you hear a "blip" and that is a block failure. You will see the block failure flash even without the "F" coming on the 7-segment display. However, you could run a solid 8 and never have a "blip." It is just that one usually begets the other. However, more frustrating is the low 0-3 errors that have blips. They are often caused by a well calibrated system that has motion stability issues. If the film weaves (either due to printing issues or soundhead issues) or has excessive vertical jitter, that is the chief cause of the low error number that blips (3,F, 3, F, 3, F....) Steve  |  IP: Logged Jean-Michel Grin Expert Film Handler Posts: 222 From: Geneva & Lausanne, Switzerland Registered: Jul 2002 posted 06-26-2003 06:57 PM                        Hi Steeve, Just a question about troubles with DA-20 digital decoder, linked with a CP-65: The case happend sometimes; the digital track is played fine, but on the next trailer, who have an analog track only, the DA20 don't make the reversion to the CP 65 for the analog sound. And best, when the digital track is present on the next trailer, the DA20 work (all the channels Leds will blink) but no sound comes out of the speakers... Have You ever seen that ? Thanks for your answer an sorry for my weak English !  |  IP: Logged Dave Macaulay Film God Posts: 2321 From: Toronto, Canada Registered: Apr 2001 posted 06-26-2003 08:20 PM                     To the best of my knowledge, Dolby is the only source for the red LED arrays used in SR-D readers. Other manufacturers use different heatsinks and mountings, and some trim the leads to fit their mounts if you order from them but the actual LED array still comes from Dolby... and Dolby is not telling where they get them from. Assuming you can mount the LED into the heatsink assembly (i.e. you have the necessary skill, and your heatsink isn't designed to make LED array replacement impossible), buying replacements direct from Dolby should cost less than buying from the reader manufacturer. White LEDs? These are actually UV LEDs with a phosphor coating that gives off light that appears white. I've seen some hints that a mix of red green and blue pigments is used. I can't find a published spectrum so far, however I assume that it's probably rather spiky. I doubt if we should assume that the good performance of the Dolby incandescent white light penthouse would mean good performance from a white LED. IR LEDs are a dead issue. The problem of not being able to visually see if the LED is working probably doomed them. The incompatibility with cyan tracks - regardless of whether you believe it's really coming, the industry has made a commitment to cyan - says "forget IR".  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 06-26-2003 08:46 PM                     To my knowledge all the LED used in reverse scan readers come from DOLBY as part of the patent licensing agreement  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 06-26-2003 09:27 PM                     Oh I wouldn't consider IR a dead issue yet....I still have some venues where visible RED was removed for IR due to visible red not being compatible with legacy prints. The industry really hasn't made a commitment to cyan...just bloated number and saber rattling. Now some countries may have made the commitment. Some countries definately have not. Steve  |  IP: Logged Larry Zuverink Film Handler Posts: 98 From: Caledonia, MI, USA Registered: Nov 2002 posted 06-27-2003 08:49 AM                     From the sounds of it I'll be shot for saying this but we have far less problems with the 701 readers than the 700 readers. Maybe we got lucky with our 701's but I would install a 701 far before a 700.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 06-27-2003 11:25 AM                     Your experiences are your experiences. They are not arguable nor should they warrant being shot. As to the Cat. 700 vs the Cat. 701. I'm curious as to the problems with the Cat. 700. About the only one that will bite everyone is the dreaded power cable connector (overheats). There is no physical way the Cat. 701 can out-track the Cat 700, presuming both calibrated to optimum. If you like the Cat. 701, you'll love the Cat. 702 though...no pesky power supply and a "go/nogo" LED to indicate how well the reader is doing. One can adjust the LED (finally) without a scope while the show is going. Another one to consider is the BACP reader which started the whole , no power supply and status LED thing. Steve  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 06-27-2003 02:55 PM                     I've never seen the 701 outtrack the 699 or 700 either. That being said I've seen it come close, but always at least a point higher than one of the white light readers could run the print at. While I'm thinking about it, I forget what the lifespan of the 699 and 700 bulbs are. I've seen these things run for 2 years without needing changing.  |  IP: Logged Alexander Alves Film Handler Posts: 33 From: Diwanman, Vasai, India Registered: May 2003 posted 06-28-2003 02:56 AM                     The bottom line folks is that the LED's which we get here in India , if replaced in a Cat701 will never give the same error rate if it were a Dolby LED. So anyone who says that the LED's are manufatured by Dolby or any of their vendors is wrong. Maybe China has started making a few of their own too?? There is some major scam going on somewhere..  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 06-28-2003 10:20 AM                     My experience has shown that the new BACP reader tracks as good or perhaps a tad bit better than the cat 699/701 penthouses does. But three is also special circuitry in there that looks at the light coming from the LED and makes compensation. The new Dolby CAT 702 also has this special USL developed circuitry weather they Dolby wanst to admit it ot not. Some trades were done between the two manufacturers as per the liscensing arrangements..... It does say Dolby Digital on the BACP!!Hummmm..... Mark  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 06-28-2003 12:21 PM                     "give the same error rate if it were a Dolby LED. So anyone who says that the LED's are manufatured by Dolby or any of their vendors is wrong" I think it is just sloppy alignment then as the led are made for dolby only  |  IP: Logged Dave Macaulay Film God Posts: 2321 From: Toronto, Canada Registered: Apr 2001 posted 06-28-2003 12:33 PM                     It's possible someone has supplied a substitute LED array, Gilway has a few that look similar in their catalog and if I shopped around in Akihabara I could probably come up with something that would fit. I don't know how you could be sure that you have the "real" Dolby array - make sure you buy from a reputable dealer?  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 06-28-2003 12:58 PM                     Dolby does not make them, themselves they are made to Dolby's specifications...I forget their vendor and I'm sure it is an exclusive agreement. I have seen an alternative LED at one of the trade shows and I thought it was BACP that showed it to me. However, until something really is released, it is vaporware in my book. Steve  |  IP: Logged Manny Knowles "What are these things and WHY are they BLUE???" Posts: 4247 From: Bloomington, IN, USA Registered: Feb 2002 posted 07-04-2003 10:38 PM                     Wouldn't you just know it..? Now I have a CP-500 (with Cat. 701) that's tracking 6-F and then totally reverting to Format 05. Strange coincidence.  |  IP: Logged

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