Heres some tests done using a high speed casio video camera aimed at the screen whilst projecting some 35mm.
The Kinoton used has a 180 degree blade so we need to get the data about how many ‘pulses’ per frame you get with this blade config.
What we will see is a pulsing of image and black.
Once we know the kinoton pulse frequency, we can work out data from the video image because each one is shot at different speeds, 300, 600 and 1200 FPS.
So say the Kinoton pulses each frame twice, so 48hz picture, 96hz image frequency, devised because each image is separated by black.
So each blade rotation has image – black – image – black, ie 4 stages. And 4 x 24 (overall FPS value is 96.
In one second (300 frames at slowest speed) we should expect to see 48 image pulses separated by black. What I’m after is the curve, or fade in and out of the black and because the video will break that one second into 300 little parts, we can count them and see where and for how long the black occurs.
On the Casio, the pixel dimension of the image goes down as the speed goes up.
So the top one is 300, then 600, then 1200 fps at the bottom.