Anyone know of a device to check fps or shutter speed on a movie camera, without shooting a roll first.
I've read about the slr's shooting a crt monitor, but with lcd there arent too many left.
movie camera fps check
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Will2
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Re: movie camera fps check
I think you need a specialized strobe.
It looks like a gun. An Arri tech showed me once but I can't remember the details. Something about the flashes matching up with the shutter to reveal the speed down to thousandth of a second.
It looks like a gun. An Arri tech showed me once but I can't remember the details. Something about the flashes matching up with the shutter to reveal the speed down to thousandth of a second.
Re: movie camera fps check
Unless you're using a crystal motor in your camera, it will run slower when film is in it, so it's somewhat of a moot point testing the frame rate of an empty camera.
One thing I've done with my Canon 814E was make a box that would send a tone through the flash trigger, which is just a switch. The tone would pulse with the shutter opening and the output would get recorded on one channel of a stereo recorder while location audio gets recorded on another. That gives you a reference for speed under load.
One thing I've done with my Canon 814E was make a box that would send a tone through the flash trigger, which is just a switch. The tone would pulse with the shutter opening and the output would get recorded on one channel of a stereo recorder while location audio gets recorded on another. That gives you a reference for speed under load.
I may sound stupid, but I hide it well.
http://www.gcmstudio.com
http://www.gcmstudio.com
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cameratech
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Re: movie camera fps check
Like this?Will2 wrote:I think you need a specialized strobe.
It looks like a gun. An Arri tech showed me once but I can't remember the details. Something about the flashes matching up with the shutter to reveal the speed down to thousandth of a second.
Very handy tool for checking crystal speeds, you point it at the shutter and if the camera is running to speed the shutter appears frozen. You can also point it at the pull-down claw to detect any variation in the movement due to play. Adjustable, as Will said, down to 1/1000 second. For the purposes of checking speed on a Super 8 camera probably not that useful, since you can't (easily) remove the lens to see the shutter on most of them, and as wado1942 mentioned, under load the camera will most likely run slower, so just checking the claw speed without a cartridge won't be accurate.
Bolex made a series of discs for their 8 and 16mm cameras to allow technicians to check the speed under load:
They locate on the the external drive shaft and work like old record player speed checkers, using the 50 or 60 hertz frequency of electric lighting so that the striped pattern remains stable at a particular rotational speed. There are two rings for each speed setting, giving an upper and lower tolerance threshhold.
Dom Jaeger
Camera/lens technician
Cameraquip, Melbourne
Camera/lens technician
Cameraquip, Melbourne
Re: movie camera fps check
There's a low-tech but relatively accurate way for you to test the running speed of your super-8 camera.
It will involve sacrificing an old super-8 cartridge, like an old Kodachrome for example, that you can't get processed anyway.
Break open the cartridge. Study the path the film takes in the cartridge. Depending on whether your camera is side loading or rear loading, you will have to cut out sections so the film can enter and leave the cartridge freely. This way you can do as many tests as you want, over and over again.
To get some degree of accuracy, you should run the camera for at least 10 seconds.
If you are testing 24 fps, you will run through 240 frames in 10 seconds.
If you are testing 18 fps, you will run through 180 frames in 10 seconds.
Super-8 film has 72 frames per foot. So have at least 4 to 5 feet of feet available.
With a Sharpie, mark an X on the film in the middle of the cartridge opening in line with the gate's aperture.
Install the cartridge and run the camera for exactly 10 seconds using a stopwatch (if you have a rear loading model, make sure to hold the cartridge in firmly while doing the test). Remove the cartridge and mark the film again with the Sharpie. Remove the film from the cartridge and count the frames between the two marks.
You can also measure the length of film. Since you have 72 frames every foot, every inch is 6 frames, etc...
Divide this number by 10 to get the running speed of the camera in fps.
The speed information should be quite accurate since the claw is actually working, pulling film through the camera.
Remember, most manufacturers of super-8 cameras considered that plus or minus 5% of the running speed was within their accepted tolerances. At 24 fps, that's a range from 22.8fps to 25.2fps.
Of course, more accurate results will be obtained if you run the camera for a longer period of time. For a 20 second test, just multiply everything by 2.
Cheers,
Jean-Louis
It will involve sacrificing an old super-8 cartridge, like an old Kodachrome for example, that you can't get processed anyway.
Break open the cartridge. Study the path the film takes in the cartridge. Depending on whether your camera is side loading or rear loading, you will have to cut out sections so the film can enter and leave the cartridge freely. This way you can do as many tests as you want, over and over again.
To get some degree of accuracy, you should run the camera for at least 10 seconds.
If you are testing 24 fps, you will run through 240 frames in 10 seconds.
If you are testing 18 fps, you will run through 180 frames in 10 seconds.
Super-8 film has 72 frames per foot. So have at least 4 to 5 feet of feet available.
With a Sharpie, mark an X on the film in the middle of the cartridge opening in line with the gate's aperture.
Install the cartridge and run the camera for exactly 10 seconds using a stopwatch (if you have a rear loading model, make sure to hold the cartridge in firmly while doing the test). Remove the cartridge and mark the film again with the Sharpie. Remove the film from the cartridge and count the frames between the two marks.
You can also measure the length of film. Since you have 72 frames every foot, every inch is 6 frames, etc...
Divide this number by 10 to get the running speed of the camera in fps.
The speed information should be quite accurate since the claw is actually working, pulling film through the camera.
Remember, most manufacturers of super-8 cameras considered that plus or minus 5% of the running speed was within their accepted tolerances. At 24 fps, that's a range from 22.8fps to 25.2fps.
Of course, more accurate results will be obtained if you run the camera for a longer period of time. For a 20 second test, just multiply everything by 2.
Cheers,
Jean-Louis
Jean-Louis Seguin
Motion Picture Camera Technician
Montreal, Canada
Motion Picture Camera Technician
Montreal, Canada
Re: movie camera fps check
To Dom: love the few glimpses of your workshop!
Cheers,
Jean-Louis
Cheers,
Jean-Louis
Jean-Louis Seguin
Motion Picture Camera Technician
Montreal, Canada
Motion Picture Camera Technician
Montreal, Canada
Re: movie camera fps check
I use a method similar to what Jean-Louis described for my Regular 8mm cameras. I have an old roll of film that I made a mark every 18 perforations and numbered each one. Each mark should be one second of run time. I get the 0 mark where I can see it and then time a run for about 10 or 20 seconds. Then I check what number it's on. Most of my cameras are Bolex and I can adjust the speed. If it's running slow I adjust the speed up and try again until I get it close. It's not the most accurate way to check the speed but I get good results with it.