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Author
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Topic: Somewhat new to this...
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John Wilson
Junior
Posts: 7
From: Farmington Hills, Michigan
Registered: Apr 2010
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posted April 11, 2010 07:51 PM
Hi All,
I have some questions regarding a Sankyo Sound 500 and some super 8 film. Just the other day I picked up the above mention projector for $30. It's in mint condition, complete with original packaging, manual, take up reel, etc. When I say mint, I mean 10 out of 10 condition. The only thing missing is the mic. I believe I got a good deal as 2 other of the same thing are going right now on Ebay for $250+! I also read a guide to buying projectors and it said "you can't go wrong with Elmo or Sankyo".
A little background on myself. I'm a professional television editor with film transfer experience, mainly 35mm on a Spirit Telecine with some 16mm thrown in. I would have done it with the spirit, but not sure if they even make a 8mm gate for it!
I've been looking for a projector in order to x-fer Some super 8 that I have, then edit and author it to DVD. The first part of my test consisted of threading some film and using an Ambico transfer box V-0612 and a Sony TRV-350 Digi 8 camcorder. I then noticed flicker, appears to be a "pulsing".
Further research concluded that in order to all but eliminate this, the projector need's to have a variable frame rate control, which the Sankyo does not have. Is this something that can be modified cheaply? I can't seem to wrap my head around the frame rate(s). What I mean is, S8 is 18fps to camcorder at 30fps, then in FCP slow the footage back down to 18fps. Will this eliminate the flicker? In my head it seem's that it would work, but I bet I will hear otherwise!
Thank you in advance for your responses and we'll chat some more!
![[Smile]](smile.gif)
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Martin Jones
Phenomenal Film Handler
Posts: 1269
From: Thetford , Norfolk,England
Registered: May 2008
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posted April 12, 2010 08:31 AM
John,
Because your projector has a 3-blade shutter and you are in the US where your Video camera has 30(app) fields per second you will need to run the projector at 20 frames per second (20x3=30x2) to avoid flicker. An external "dimmer" will not vary the speed.
Also, you will need to choose a suitable shutter speed for the camera,for the same reason. Trial and error is needed here.
For the speed problem, one or other of your presets will hopefully achieve the correct speed. If not, you may need to change some of the values of the board resistors (not to be undertaken lightly is you are not "electronics literate") to achieve the desired result. It's also useful to extend the preset out of the machine in the form of a "manual" potentiometer so that smooth adjustment of speed is possible during actual transfer.
As the transfer speed is different to either 18 or 24 fps, or even to the original camera speed, you will have to capture to a computer using an editing software that can correct for the speed of both picture and sound.
That's a brief run down;but the best results require lots of experimentation!
Good luck!
Martin
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Retired TV Service Engineer
Ongoing interest in Telecine....
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Martin Jones
Phenomenal Film Handler
Posts: 1269
From: Thetford , Norfolk,England
Registered: May 2008
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posted April 12, 2010 09:03 AM
First, try with the Camera at 1/30 and adjust one or other of the trimmers to see whether you can either increase or decrease the projector speed to 20 fps, i.e. when the flicker is minimal. You need to be able to adjust the speed such that the flicker reduces with turning the preset and then increases again if you turn it further in the same direction. If you can achieve this, set it to the minimum point, and then try different shutter speeds on the Camera to see what effect it has.
If you CAN achieve the correct speed WITHIN the range of one of the presets, that one can be removed from the board and an EXTERNAL potentiometer ( yes, RadioShack would probably have one) of the SAME value on extension wires wired in it's place. Otherwise, resistor values will have to be changed.
BUT, I repeat,DON'T attempt this unless you understand the principles involved and are competent with electronic wiring and measurement techniques.
I do not have schematics for your machine, so cannot advise in more detail. If you can find a schematic for the machine and a competent "hands on" TV or electronics hobbyist locally, then you are in with a chance.
But don't do anything you cannot easily reverse!!
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Retired TV Service Engineer
Ongoing interest in Telecine....
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Martin Jones
Phenomenal Film Handler
Posts: 1269
From: Thetford , Norfolk,England
Registered: May 2008
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posted April 13, 2010 02:52 AM
John,
Yes, the slower shutter speed is masking the flicker in the "judder" you are experiencing! This "judder" is actually present ALL the time but not always obvious; the slow shutter speed is "averaging out" the brightness variations (flicker) due to the speed incompatibility.
The MOST important setting is the projector speed; get that right and the problems will be substantially lessened. From that point, it is CAMERA shutter speed that is important. My guess is that with your camera you will need the fastest speed you have...1/30th. Anything slower than that will show up as "blurring" or "judder"; 1/60 or 1/120th would be better, but
you do not have those.
The importance of camera shutter speed is related to the fact that the projector displays images in a "stop-start" manner, while the camera reads the images continuously. In the optimum case, a fast shutter speed will "snap" a still picture into the camera which will then "read" it during the camera "dark" period. For the very best results it is necessary to ensure that there is a "phase" synchronization as well as a "speed" synchronization between projector and camera shutters, but this is beyond the scope of a simple projector/camera set-up. Tiny "up and down" manual adjustments of speed using an external speed control can help achieve this; more complex electronic control (outside the scope of this) can produce very satisfactory results.
Speed control FIRST, then play with other aspects.
EDIT: This is not intended for John, but generally. For NTSC 60hZ camera users, fitting a 5 blade shutter enables "flicker-less" transfer at both 18 and 24 fps, BUT there may still be minor problems with the phasing and correct shutter speeds on the Camera. For ALL video Standards, "Frame-by-Frame" in one form or another is best for the Amateur enthusiast, but this needs some projector engineering.
FURTHER EDIT: Will now be out of circulation until 22nd; back then!
Martin.
[ April 13, 2010, 10:56 AM: Message edited by: Martin Jones ]
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Retired TV Service Engineer
Ongoing interest in Telecine....
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