I just aquired a bell howell 471 projector which has a step motor for fake slow motion (6 fps) and about 2 or 1fps). Running a 400' reel at 1fps would take a long time!
was wondering if anyone has transfered film using a slower speed with the video or scanner in sync - better results? or should I just stick to the 16/18fps on a variable speed projector with the ability to increase or decrease slightly to prevent projector roll.
film transfer with step motor projector.
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carllooper
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Re: film transfer with step motor projector.
There are advantages but they require some additional work. You basically want to avoid capturing images when the projector's shutter blade is obscuring the image or otherwise minimise the influence of the shutter blade on the result.
1. Use a digital stills camera that takes a picture when the motor is stopped - using some sort of trigger slaved to the projector advance.
2. Use a video camera in which you then blend a sufficiently large number of video frames together (for each film frame), making any contributing video frame that caught the shutter blade, minimal with respect to the other contributing video frames that didn't.
There are other techniques such as recording a signal of some sort against those frames that caught the shutter blade, (or against those that didn't) and removing the offending frames in the digital post - need some custom software to do it. Some avisynth coding could do it. The signal could very well be an optical one - ie. recorded in the image area.
1. Use a digital stills camera that takes a picture when the motor is stopped - using some sort of trigger slaved to the projector advance.
2. Use a video camera in which you then blend a sufficiently large number of video frames together (for each film frame), making any contributing video frame that caught the shutter blade, minimal with respect to the other contributing video frames that didn't.
There are other techniques such as recording a signal of some sort against those frames that caught the shutter blade, (or against those that didn't) and removing the offending frames in the digital post - need some custom software to do it. Some avisynth coding could do it. The signal could very well be an optical one - ie. recorded in the image area.
Carl Looper
http://artistfilmworkshop.org/
http://artistfilmworkshop.org/
Re: film transfer with step motor projector.
For frame by frame capturing, search for posts by VideoFred from Belgium. You need a video camera that can capture off emulsion (or any way the frame is being displayed via projector lens for example) and capture is triggered by a signal when frame is not coverd by projector shutter blade.
For capturing at full speed, what is the number of shutter blades of this projector and what is the AC frequency in the country you are in? Number of blades and frequency should give you an idea at what speed projector should be running.
Rule is: FPS speed multiplied by number of shutter blades should by an integral factor of the AC frequency.
Example: Blades = 3, Frequency = 60 HZ -- projector should be running at 20FPS since 3x20 = n(60) where in this case n is the integral factor and is equal to 1.
Another example: At FPS = 18 and frequency = 60, number of blades should be 10 since 10x18 = 3x60
Or, at FPS = 24, you need five blades at frequency 60 since 5x24 = 2x60
and so on.....
Frame by frame or at full speed, results should be equally fine depending on optics you are using to capture, speed of capturing system, and the middle system you have between capturing optics and emulsion of film.
For capturing at full speed, what is the number of shutter blades of this projector and what is the AC frequency in the country you are in? Number of blades and frequency should give you an idea at what speed projector should be running.
Rule is: FPS speed multiplied by number of shutter blades should by an integral factor of the AC frequency.
Example: Blades = 3, Frequency = 60 HZ -- projector should be running at 20FPS since 3x20 = n(60) where in this case n is the integral factor and is equal to 1.
Another example: At FPS = 18 and frequency = 60, number of blades should be 10 since 10x18 = 3x60
Or, at FPS = 24, you need five blades at frequency 60 since 5x24 = 2x60
and so on.....
Frame by frame or at full speed, results should be equally fine depending on optics you are using to capture, speed of capturing system, and the middle system you have between capturing optics and emulsion of film.
camera8mm wrote:I just aquired a bell howell 471 projector which has a step motor for fake slow motion (6 fps) and about 2 or 1fps). Running a 400' reel at 1fps would take a long time!
was wondering if anyone has transfered film using a slower speed with the video or scanner in sync - better results? or should I just stick to the 16/18fps on a variable speed projector with the ability to increase or decrease slightly to prevent projector roll.