2-perf Cameras by ALEX GEORGIOU DESIGNER / ENGINEER IN CINEMATOGRAPHIC EQUIPMENT TO THE FILM INDUSTRY SuperVision 235 Techniscope.Euro Address: 44 Dunkery Rd. London SE9 4HZ U.K. E-mails: admin@supervision2perf.com alex-geo@hotmail.co.uk Web: www.supervision2perf.com Tel:(44)20 88572431 Skype--tech235 |
Talking 2-perf. Camera Conversions Re: Arri IIC If you own an Arri IIC and you are lucky enough to own or can obtain an Arri techniscope conversion kit, then it can make things a lot easier. Incidentally, there are four components in the kit - the gate, gearblock, intermediate fibre gear which drives the magazine film sprocket, and of course the cam. (For the engineers out there who are thinking of shifting the cam towards the centre, you would be surprised at the behaviour of the claw.) As for the ground glass, you can grind the original and have new markings put on, or you can insert a mask (which I prefer). It saves money. If you don't have the above components, then you take a different route which involves a great deal of engineering, ingenuity and of course money - in fact you can convert any Arri II cameras, i.e. A, B and Cs - good luck to you! Re: Kinor 35 For this camera, as I mentioned above about techniscope conversion kits, well forget it. There aren't any. I converted one of these cameras a few years ago (in fact, two cameras - one is mine) for Solid Entertainment. The conversion involves a lot of engineering work and of course patience. There are four operations involved with this camera. First, the gate which you can mask off to accommodate the techniscope format. Incidentally, it's 22.05 x 9.47mm ( Imperial 0.868" x 0.373"). Second, the ground glass which you can also mask off (i.e. it's less disruptive to the cameramen). Third, the movement, which involves manufacturing and replacing the original claw pivot block, and relocating it to accommodate the 2-perf pull. Lastly, the film sprocket drive - the ratio has to be doubled from 3:1 to 6:1. Good luck! Re: Eclair CM3 If you are an owner of one of these cameras and you are fortunate enough to own the techniscope version, then you are in business. You can easily switch over from the standard 4-perf to 2-perf pull. Of course, you need special magazines for the 2-perf version. Alternatively, the standard 35mm or the dual gauge 16/35 can be modified to a 2-perf. A few years ago I designed a techniscope conversion kit for this camera (the first in the world), on which you can use ordinary standard 35mm magazines without modification and it saves you money, but I'm afraid you need a qualified engineer to install it. This involves working inside the body, i.e. stripping down the gearbox, discarding and adding new gears, new connecting rod, re-machining the eccentric etc. P.S. If you own the 16/35 version please discard the 16mm pull-down claw - it serves no purpose, and of course the camera is quieter. 3-Perf Camera Conversion 3-perf camera conversion is basically the same as 2-perf with one exception, and that depends on the number of teeth of the feed and take-up film sprockets , i.e. Arri, Eclair, Mitchell, and some other cameras. Their sprockets have to be replaced,- which is a giant step (is it worth it?). It so happens that the Kinor 35 with its 12-teeth take-up sprockets, is suitable, i.e. 12 divided by 3 = 4, hence 4:1 ratio drive |
FILMING IN TECHNISCOPE Filming in techniscope is a technique which brings about a saving of 50% in 35mm raw stock, and halves the cost of film processing. Developed by Technicolour Italiana, as I recall in 1963 by Dr. Giulio, it uses half the height of the standard frame, i.e. two perforations pull, instead of four, with aspect ratio of 2.35:1. For television presentation, it can be transferred and televised without any further modification. It is ideal format for modern widescreen TV, and certainly the quality is far superior to Super 16, and with the popularity of HD, filming in 35mm is a perfect format, also the colour rendering of the film is far superior to video. The only drawback is 2-perf camera availability. For cinema presentation, the frame has to be blown to a standard 4 perforation, and by special process, squeeze the image to 2:1 ratio with an anamorphic system, thus retaining the aspect ratio of 2.35:1 (Panavision), also saving the very high cost of using anamorphic lenses on the camera. Camera ground markings and projector aperture should have readings of 22.05 x 8.89mm. Examples of the film running times with Techniscope: at 24 fps 61 Mtrs 200' -- 4-26 min--sec 122 '' 400' -- 8-52 '' '' 152 '' 500' -- 11-06 '' '' 305 '' 1000' -- 22- 14 '' '' |
DIFFICULT TO LOAD MAGAZINES? There are certain magazines, i.e.the dreaded Konvas, CM3 Cameflex, which users find it an extremely difficult task to load. I've read various articles on this subject, but I'm not impressed. My advice on this is to load the film in daylight, so you can see what you are doing. Don't panic! It is perfectly normal. Many years ago I invented a system and manufactured loading cassettes to do this. (You can do this with any magazine - 16mm or 35mm). First and foremost, you need a loading cassette,( see pictures ) The whole idea is to transfer in the dark the unexposed film and drop it inside the cassette and shut it. Make sure you leave enough film outside to load the magazine. The next stage, now load the magazine in daylight so you can see what you are doing. When you are ready, in the dark, take out the unexposed film and drop it inside the magazine and close the lid. That's it! Easy as that. In theory you can have as many loaded cassettes as you like, and keep them ready for when you need them. I have been advising cinematographers and using this system for many years now and it's a perfect system. You will be kicking yourself when you find how easy it is. For information on cassettes drop me a line. |
ABOVE THE 2 PERF MITCHELL S35 Mk II Above pictures show the upgraded camera designed and converted by me to 2-perf. Digital electronics and brushless motor drives the camera, also includes video assist. The counter has been replaced with digital reader. Most of the gears inside the body have been removed, also the magazine drive has been re-designed including the shutter adjustment. |
| Exposure times formula for various shutter angles Example: 180 degree shutter at 24 fps - 360 degrees divided by 180 = 2 x 24 fps = 1/48 second (Always divide the shutter angle by 360 degrees) |
| ECLAIR CM3 2perf Bodies We have 7 CM3 bodies to dispose of. All have been modified to 2-perf and are in perfect working order. These cameras are suitable for those who already own a CM3 camera and can use their own mags and motor. (No modification to mag drive is needed).These cameras have to go for we have other urgent commitments hence a give-away price at £750 + P&P each, or will sell all as a job lot. Once these cameras go we will not convert any more of these cameras. Our workshop will not be available from 27th April until 16th June 2009. P.S. We hold some spares for these cameras and we provide support if needed.................all mirrors (shutters) have been resilvered on these cameras. |
| Arri 2-Perf Techniscope ( see photos above )Camera designed and modified by me. |
4 are sold