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Author Topic: Were to buy an gate alignment tool? John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 10-23-2003 05:33 PM                        KS-1870 "Kodak Standard" Perfs having a pitch of 0.1870 inches, and a hole size of 0.1100 x 0.0780 inches -- the perforations found on almost all release prints today. CS-1870 "CinemaScope" Perfs with a pitch of 0.1870 inches, and a smaller hole (to make more room for magnetic tracks in the original CinemaScope format). http://www.kodak.com/US/en/motion/support/h1/sizesP.shtml#perfs http://www.kodak.com/CA/plugins/acrobat/en/motion/ref.pdf http://www.smpte.org/smpte_store/standards/pdf/numindex.pdf  |  IP: Logged Steve Kraus Film God Posts: 4094 From: Chicago, IL, USA Registered: May 2000 posted 10-23-2003 05:56 PM                    In a nutshell, KS (Kodak Standard) perfs are the ordinary perforations you see on 35mm release prints (and 65mm neg and 70mm release prints). They look roughly like little Academy apertures. CS (CinemaScope) perfs were used on release prints with 4-track magnetic sound. They are narrower and look roughly squarish. BH perfs are used on 35mm camera negatives and some intermediate stocks. They are akin to KS in rough size but the sides are curved as though part of a circle while the tops and bottoms are straight across. Numbers like 1870 refer to the spacing or pitch which means the distance from a particular part of one perf to the same part of the next perf, like center to center or top edge to top edge. Pitch is important, as John has explained, when printing on a high speed contact printer because the two films must pass over a large sprocket bipacked (one on top of the other, piggyback) and so the film stock being printed to which is on top is going to be at a very tiny greater diameter simply by being one film thickness farther out. So the pitch must be a tiny bit greater if the film is not to slip against the other and blurring the image. Edit: typo fixed [ 10-23-2003, 07:03 PM: Message edited by: Steve Kraus ]  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 10-23-2003 06:06 PM                        As Steve notes, optimum steadiness on a continuous contact printer requires that the printing original be "short pitch" and the raw stock be "long pitch" -- for 35mm film, 0.1866 and 0.1870 inches, respectively. For 16mm film, 0.2994 and 0.3000 inches respectively. If they can't print short-to-long, labs should use a pin-registered printer rather than a continuous contact printer.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 10-23-2003 06:16 PM                     KS-1870 and CS-1870 refer to the perforation definitions. The "KS" part refers to "Kodak Standard" Which is a rectangular perforation. The "CS" part refers to "Cinema Scope" which is a square perforation. The CS perforation came about to gain space on the film for the magnetic stripes used in the CinemaScope process. They have also been found to be more durable. However, magnetic 4-track is about all that used that perforation so they are much more rare. I don't think anyone still perforates to CS anymore, John would know better. The Second part of the definition is the "1870" part which refers to the pitch of the perforations. Both are 1870 and they both have a 187-mil (.1870") pitch. There is another popular pitch in the labs and cameras of .1866" Take a guess what its name is .... It is BH-1866. The "BH" refers to Bell and Howell. This perforation is most seen in theatres on SMPTE's 35-PA (aka RP-40) in the Black & White format. The BH perforation looks like a round circle with flats on top and bottom. Steve  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 10-23-2003 08:47 PM                        quote: I don't think anyone still perforates to CS anymore, John would know better. As I noted earlier, I'm not even sure Kodak still has a perforator set up with a CS punch and die set, as 35mm mag prints haven't been made for almost two decades. Print film with CS-1870 perfs is certainly no longer a catalog listed item: http://www.kodak.com/US/plugins/acrobat/en/motion/catalog/colorPrint.pdf  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 10-23-2003 08:57 PM                     To get this thread back on the correct track I thought I'd let you guys know that Strong has available a trap alignment gauge made especially for the Simplex curved gates. It'll also work fine in the Century SA as well. List price is just under a hundred bucks. An important note when setting up Simplex traps... Be sure the relationship of the intermittent sprocket shoes and the sprocket itself are correct. If its a bit off you might shave the sides off of the teeth on a VKF sprocket. Although the shoe design was changed to accomodate the wider VKF tooth design there are many incorrect(ie: made for CS type perfs) intermittent sprocket shoes still in use out there. The best thing is to install an entire new shoe assy on a given machine if you're in doubt. If the inner sides of the teeth get shaved down it cannot be seen without pulling the sprocket or movement fomr the machine. One tell tale is that the machine will probably produce a ton of film dust. Mark @ CLACO  |  IP: Logged Steve Kraus Film God Posts: 4094 From: Chicago, IL, USA Registered: May 2000 posted 10-23-2003 09:10 PM                    I have some 4-track here from a 1986 release; no date code or other ID visible on the stock, though.  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 10-23-2003 09:11 PM                     To get this thread back on the correct track I thought I'd let you guys know that Strong has available a trap alignment gauge made especially for the Simplex curved gates. It'll also work fine in the Century SA as well. List price is just under a hundred bucks. There as a gauge made just for the SA but Strong decided to let the Simplex gauge pull double duty. If ya need to get one just call your Strong dealer..... An important note when setting up Simplex traps... Be sure the relationship of the intermittent sprocket shoes and the sprocket itself are correct. If its a bit off you might shave the sides off of the teeth on a VKF sprocket. Although the shoe design was changed to accomodate the wider VKF tooth design there are many incorrect(ie: made for CS type perfs) intermittent sprocket shoes still in use out there. The best thing is to install an entire new shoe assy on a given machine if you're in doubt. If the inner sides of the teeth get shaved down it cannot be seen without pulling the sprocket or movement fomr the machine. One tell tale is that the machine will probably produce a ton of film dust. Mark @ CLACO  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 10-24-2003 08:55 AM                        I checked about the possibility of providing stiff 7-mil polyester leader with CS-1870 perforations for use as an alignment tool, per Steve Guttag's comments on "steel film". Unfortunately, since no one has purchased CS-1870 perforated print film in about 20 years, all of Kodak's perforators have been switched over to other perforation types. So the stiff leader with KS-1870 perforations should be used.  |  IP: Logged Mark J. Marshall Film God Posts: 3188 From: New Castle, DE, USA Registered: Aug 2002 posted 10-24-2003 02:20 PM                    Thanks for the info from all. So CS-1870 is the technical term for "Fox Sprockets?"  |  IP: Logged John Pytlak Film God Posts: 9987 From: Rochester, NY 14650-1922 Registered: Jan 2000 posted 10-24-2003 03:55 PM                        Yes. CS-1870 = Fox Hole (CinemaScope was introduced by 20th Century Fox). Here's links to information, photos, and illustrations: http://www.widescreenmuseum.com/widescreen/wingcs1.htm http://www.widescreenmuseum.com/widescreen/cinemascoperef.htm  |  IP: Logged Frank Angel Film God Posts: 5305 From: Brooklyn NY USA Registered: Dec 1999 posted 10-26-2003 09:23 AM                        I understand that prints no longer carry mag tracks, and stop me if I am being too logical here, but if Fox sprocket holes were proven to be stronger and more robust than KS, why did Kodak and the labs stop using them, just because they stopped stripeing the prints with mag tracks? Why didn't they just keep making prints with CS sprocket holes -- almost all projectors were equipped with CS sprocket drives, even those that didn't have mag penthouses, so it wouldn't be like theatres wouldn't be able to run CS prints. Why abandon the known advantage of the mag sprocket hole configuration just because the mag stripes themselves were no longer used? Besides, wouldn't using the CS sprocket hole configuration leave more space for Dolby's digital track, perhaps requiring less compression because of the larger digital footprint? There could even be room for an additional DTS backup code opposite the sprockets holes on the other side. Digital sound might even be reliable enough that you wouldn't need an analog track (ooops, sorry, that was Kodak's idea). Even SDDS tracks could have larger footprints, although that will quickly become free space once SDDS finally gasps its last death rattle....in 8 tracks surround stereo. There would even be room for the labs to print reel numbers, footage, sound formats and incept dates along the entire length of the print. See, lots of advantages....or am I missing something? In the same vein, I still can't see why they continue to make 16mm prints with the frame line exactly in the middle of the sprocket hole. It may have been OK eons ago when they were using overlap cement splices, but to continue to use it today when because of poly stock, the overlap method cannot be use and ONLY taped butt splices can be used, makes no sense; a tape slice on a cut sprocket hole makes a weak, piss-poor joint. IMHO, it's idiotic to continue to make prints that way only because that's the way it was done last century. Besides, surely for the lab to move the position of the frame down half a frame height equidistant between the two sprocket holes can't be that difficult; that would put the intermittent/claw pull-down force against an undamaged sprocket hole rather than where it is now, on what essentially is a cut sprocket hole that is being held together with two pieces of tape. So if they made me CinemaKing instead of CinemaDude, all 35mm prints would have FoxHoles with reel numbers printed the lenght of the reel as well as all the other information mentioned above and (I am not done proclamating) all 16mm prints shall have the sprocket holes in between the framelines. Frank And PS....And as long as I am CinemaKing, I further proclaim that the 1.85 format shall no longer be cropped spherical wide screen, but it shall use the full Scope aperture with the appropriate mild anamorphic squeeze to make 1.85 -- bright, clear and without wasted film stock. And parenthetically, anyone who is found speaking the words "3 perf Compact Distribution Print" would be taken to a damp tower someplace and forced to watch GLITTER over and over, never to be heard from again, except on a quiet summers' evenings when far off in the distance you can hear someone from UA Theatres crying, "No, no.... please, not again." Being King is fun.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 10-26-2003 10:05 AM                     I'll let you have most of that except the 16mm thing... Tape is neither the only nor best way to splice film. Olden days...cement, modern days ultrasonic. As to strength...I have yet to have a problem with the 16mm perf where it is. I would oppose a change in the 16mm format (or most any film format) at this late stage. 16mm is progressively heading toward a niche so having a dramatic change at this point would be devistating...think about all of the claw based projectors out there that are based on the current design...you "frame" by moving the aperture up and down (better ones also move the lens with the aperture so the image doesn't shift up/down too)...most would not handle a half-frame change. Steve  |  IP: Logged Steve Kraus Film God Posts: 4094 From: Chicago, IL, USA Registered: May 2000 posted 10-26-2003 10:33 AM                    Well, I presume he was just speaking in the hypothetical. Frank, I'm not going to appoint you CinemaKing (yes, I have the power--see my sig) if you think center perf 16mm is advantageous. Some of that width you think you are gaining must be wasted anyway due to rubbing contact with rollers, gate runners etc. And it's not like it's free--you're going to pay for it with either less frame height or greater footage requirements. However, the main objection is the greater damage that will result when something goes awry, especially in a format that more often uses claw pulldown instead of intermittent sprockets. As long as we are rambling about formats that will never be I will enter into the record a college-years fantasy format I called Vista-8 or V8 for short which was horizontal motion Super 8 with triple sized frames primarily for blow-up to 35mm.  |  IP: Logged Carl Martin Phenomenal Film Handler Posts: 1424 From: Oakland, CA, USA Registered: Feb 2002 posted 10-26-2003 05:05 PM                        steve, i think frank wants to leave the 16mm perfs on the edge of the film, but centered vertically on the frames. you're talking about putting them down the middle of the film, between the frames, like in 9.5mm. while i think frank's idea is better than what we have now, it's not worth obsoleting all existing 16mm projectors. well i suppose you'd still have to keep them around for older prints. carl  |  IP: Logged

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