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Author Topic: Loops Chris Byrne Expert Film Handler Posts: 102 From: Kirwan, Australia Registered: Jan 2003 posted 01-02-2004 06:33 AM                     I read with interest in the Tips section about correct threading of a projector. On the 2nd page there was a picture of top and bottom loops at their highest / lowest points. Is there a tolerance for how many perfs you can be out? While I would say my loops are spot on to the tipsheet, a few of the people in my booth are either one perf bigger or smaller (mainly the top loop), however I haven't noticed any presentation flaws. The projectors are Kinoton FP30D's. If there is no tolerance, what are the downfalls of erring either way other than those mentioned in the tip sheet.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 01-02-2004 06:50 AM                     With the intermittent is the middle of the dwell the lower loop should of the size to ensure with Pix Start in the gate the sound diamond is across the sound reader and the upper loop to ensure that the diamond is across the mag head if that is what is in use  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 01-02-2004 07:29 PM                     The tips page was specific to Christie projectors. No other make/model projector will match those loop sizes. Until such time comes that I have access to a wide variety of equipment and lots of free time to document other threading, you will have to read the manual, follow Gordon's tip as well as do a little fine tuning on your own to find the true ideal size.  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 01-02-2004 09:42 PM                        Again, the separation between the picture frame and the corresponding analog sound on the print is 21 (+/- 1/2) frames. Threading with 21 frames between the picture aperture and the analog sound pickup will normally put the sound in sync if the audience is VERY CLOSE to the speakers. For most theatres, you want the sound to lead the picture by about 1 frame (1/24 second), so it reaches the center of the theatre in sync. So the normal THREADING offset is 20 frames, which is the separation normally indicated by the "diamond" on the head leader.  |  IP: Logged Scott Norwood Film God Posts: 8146 From: Boston, MA. USA (1774.21 miles northeast of Dallas) Registered: Jun 99 posted 01-02-2004 09:45 PM                        Assuming that you don't have/aren't using a digital or mag penthouse reader, the upper loop usually has plenty of tolerance--EXCEPT ON THE FP30. I forget exactly what the film would hit (feed sprocket film stripper? someone will know...), but I remember that it's really easy to cause a scratch if the upper loop is too big. Lower loop should be set to give correct sound sync for the room (as Gordon mentioned); it should be slightly larger for small rooms and slightly smaller for huge theatres.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 01-03-2004 10:28 AM                     Upper loops being to large is also an issue on cinemecanicas (hits the apperture changer or the loop trip same thing on ernaman 8&9's also on simplex it can buckle and scratch  |  IP: Logged Steve Scott Phenomenal Film Handler Posts: 1300 From: Minneapolis, MN Registered: Sep 2000 posted 01-06-2004 10:39 AM                     Century C's and SA's have a small tolerance for the top loops as well. I have some projectionists that make very small loops to keep from scratching the prints, as if they don't wanna learn how to make a loop that looks good on screen - free of shaking and focus problems. But the bottom loops of the centuries can be made fairly big without causing scratches. Not as big as the Christies, but certainly a larger tolerance than the centuries top loops.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 01-06-2004 11:20 AM                     Century loop size is very simple with the movement in the dwell position just lay the film over the open padroller arm and close it the swing of the pad roller arm is the loop size On the JJ that doesn't work though  |  IP: Logged Brad Miller Administrator Posts: 17775 From: Plano, TX (36.2 miles NW of Rockwall) Registered: May 99 posted 01-06-2004 03:21 PM                     Steve, the bottom loop if made too big on a Century DOES cause scratches. It's just that most theaters don't have enough light on screen to reveal them. At the bottom loop's smallest size, there is just about only enough room to put a Sharpie marker in there. Try Gordon's threading trick. Even if you use that stupid, stupid, stupid old theory of "two fingers" in that loop, it's TOO BIG.  |  IP: Logged Gordon McLeod Film God Posts: 9532 From: Toronto Ontario Canada Registered: Jun 99 posted 01-06-2004 05:49 PM                     Actually that was from a old century manual  |  IP: Logged Ian Bailey Master Film Handler Posts: 317 From: Nambucca Heads, Australia Registered: Jun 2003 posted 01-09-2004 04:49 AM                     Being only new to this game I am still a bit confused.John states that you need 20 frames between the picture aperture and the analog sound pickup,this obviously governs the size of the bottom loop.Steve says that the top loop is critical for good presentation(picture shake and focus).What governs the size of the top loop apart from not letting the print touch any part of the projector.We have Simplex 35 model 1050 projectors any advice on threading up or loop sizes would be apreciated.  |  IP: Logged Michael Schaffer "Where is the Boardwalk Hotel?" Posts: 4143 From: Boston, MA Registered: Apr 2002 posted 01-09-2004 04:56 AM                        quote: ON THE FP30. I forget exactly what the film would hit (feed sprocket film stripper? Older models used to have a pin on top of the gate which served as an additional failsafe in case of film break. If the film broke then it would switch off the projector. You wouldn`t see the naked light on the screen this way. 6 or so years ago, they abolished that. This wouldn`t usually cause scratches as it would shut the projector down when hit by film. Sometimes it would also keep the projector from starting when it was stuck in the off position. A colleague of mine used to say if you can`t thread the projector without the film hitting the pin, then you shouldn`t be allowed near the machine anyway. I think he was right.  |  IP: Logged David Graham Rose Expert Film Handler Posts: 187 From: Cambridge, UK Registered: Sep 2002 posted 01-09-2004 01:40 PM                     Greetings from LA where I reside in preparation for the ITEA Newer Kinoton FP30E's have a modified top sprocket compared to older version. It is possible to make the top loop considerably larger than of old, and is indeed desirable should one be taking advantage of the 'Shuttle' mode of operation. Reverse operation of 'Shuttle' can result in damage to the film and gate should the uper loop be too small. I look forward to meeting many of you over the next few days at the ITEA. I now sport my winter beard growth, should any of you fail to recognise me with said facial adornment. Good Afternoon, from a very jet-lagged Academic  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 01-10-2004 12:32 PM                        I will be attending the ITEA Seminar Series in Los Angeles next week too. See you at Monday's reception!  |  IP: Logged David Graham Rose Expert Film Handler Posts: 187 From: Cambridge, UK Registered: Sep 2002 posted 01-10-2004 03:15 PM                     Greetings John I will endeavour to seek you out. It would be great to host you at Cambridge for a series of lectures on raw stock production for my '04 undergraduates if we could tie it up!  |  IP: Logged

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