modify frame rate on cheap cameras?

[metaT8]

Does anyone know where I might find instructions on how to open up a canon 310 or 514 and over-crank the FPS?

I know there must be a potentiometer in there which controls film speed but I don't want to guess.

Thanks

m

[jpolzfuss]

Hi,

two points:
a) Modifying the fps-rate also means modifying the auto-exposure system. (Okay, at the canon 310xl one might use nd-filters in front of the exposure-meters lens (when the camera is set to faster than 18fps) or in front of the "normal" lens (when the camera is set to slower than 18fps).)
b) Unless the camera was available with another lens as a 18+24 fps-model there's a very high chance that the potentiometer can only be used for fine-tuning the fps-rate (+- 1 fps). Hence it's very likely that you'll end up changing gears or the motor...

Jörg
P.S.: A Super8wiki-entry that might help: Minolta: how to modify XL-42, XL-64 to add 24 fps

[aj]

One technique is to connect a power source directly to the motor. By regulating the voltage you can make it go faster or slower. Some sort of automatic B

[reflex]

two points:
a) Modifying the fps-rate also means modifying the auto-exposure system. fps-model there's a very high chance that the potentiometer can only be used for fine-tuning the fps-rate (+- 1 fps). Hence it's very likely that you'll end up changing gears or the motor...

I don't know about the Canon, but I've had great success modifying low-end Bauer cameras such as the C 107 XL. It's an 18 fps camera, but the speed potentiometer can be ramped up to 24 fps/25 fps (and probably well beyond) and the exposure meter can be tweaked to match the new frame rate. Everything is accessible by removing the side panel, too.

[Will2]

I've had great success modifying low-end Bauer cameras such as the C 107 XL. It's an 18 fps camera, but the speed potentiometer can be ramped up to 24 fps/25 fps (and probably well beyond) and the exposure meter can be tweaked to match the new frame rate.

I'm curious, how do you measure the actual frame rate? This is something that has perplexed me when it comes to Super 8 camera (or any movie camera) repairs...

[reflex]

I'm curious, how do you measure the actual frame rate? This is something that has perplexed me when it comes to Super 8 camera (or any movie camera) repairs...

I wrote this a couple of years ago...

I've come up with a better way of setting a camera to exactly 24fps, 25fps, or 18fps. You'll need a computer monitor (CRT, not LCD) -- most recent CRTs can be set to refresh at multiple rates.

Adjust your monitor's screen refresh rate to 72 Hz. This is exactly 3 x 24fps or 4 x 18fps. Make sure your monitor is displaying a nice, white page (makes the process easier).

Point your Camera at the screen and start "shooting" without film. open the film door and "shoot" the screen while looking through the film gate (you'll have to practice to find a viewing angle that allows you to see the most image). The image on the monitor will appear to faintly strobe. Adjust the speed of the camera so that the dark bar in the image doesn't roll and you're set to exactly the right speed. For best effect, I found it easiest to focus my eyes on the film gate to see the "strobing" effect and to adjust the camera with the side panel removed so I can tweak the speed in real time.

To SET TO 25FPS:

Same as above, but set the screen refresh to 75 Hz (3 x 25 fps). Of course, Europeans could just use a PAL TV set which refreshes at 50 Hz (2 x 25fps).

[Tom Terrific]

neat trick

[jpolzfuss]

I'm curious, how do you measure the actual frame rate?

Hi,

other than using reflex's nice trick you might use a device like the
"Screen Check SC200" (alias 'Speed "rpm"'):
http://www.ffr-film.de/de-bauer-.html
Of course you would have to point your camera to a constant light source (no monitor, no tv, no neon-light, ...). Of course it'll cost you more than reflex' trick (that is if you do have such a monitor), but the device can also be used to check the projector's frequency, ... .

The device is also available at these two shops - the first one is a "wellness"-shop (the device is used as test whether your stress comes from one of your lamps flickering), the second one is a general electronics shop (with the device located as a test-device in the "remote controlled DIY cars/planes/ships/..."-section):
http://www.wellness-shop.com/screen_checker.html
http://www.elv.de/output/controller.asp ... tail2=3607
Hence I guess that it should be available worldwide in all kind of different shops.

Jörg

[Pj]

Hi

I was wondering if the frame rate speed be changed on a Nizo 156 from 24fps to 25fps?

P.

[reflex]

Hi

I was wondering if the frame rate speed be changed on a Nizo 156 from 24fps to 25fps?

P.

Yes. You'll have to remove the side cover where the control panel is and find the little speed control potentiometer. As I recall, it's a small copper lever that be moved gently by hand to adjust the speed.

Remember that most cameras (including the 156) do not have digitally controlled speed circuits. The speed may vary as the batteries drain and depending on what type of batteries you use. In other words, even if you set your camera to 25 fps with a fresh set of batteries, it may end up running at 24 fps or less as you shoot.

[Pj]

Thanks, when you say 'most cameras don't have digital speed'. That's almost every Super 8 camera isn't it?

P.

[jpolzfuss]

Thanks, when you say 'most cameras don't have digital speed'. That's almost every Super 8 camera isn't it?

Yes, there are only a few Beaulieu-models that are "crystal sync'ed" by default. Nevertheless there are several cameras (Beaulieu, Pro8mm, Canon, Nizo, ...) that can be converted to "crystal sync'ed":

viewtopic.php?t=18656

[reflex]

Thanks, when you say 'most cameras don't have digital speed'. That's almost every Super 8 camera isn't it?

Jörg hit the nail on the head. The Canon 814 XL-S and 1014 XL-S also have digitally controlled frame rates, but they don't use PLL circuits to monitor and adjust the speed perfectly so aren't "crystal sync'd" and not necessary bang-on.

[James E]

The Minolta XL 42/64 modification link posted by jpolzfuss was discovered and posted to S8wiki by me. I have some fuzzy pictures of the process I never posted. If they're helpful I'll send them to anyone who wants them or perhaps I can post them to the wiki if I could figure out how to.

Another thought on the Minolta modification is if you replaced that point contact switch with a potentiometer you just might have yourself a varible speed camera. Alas I long ago sold both of those cameras so I no longer have them to experiment with. Anyone have an XL 42 or 64 to try this with?......
Cheers,

[Andersens Tears]

The Minolta XL 42/64 modification link posted by jpolzfuss was discovered and posted to S8wiki by me. I have some fuzzy pictures of the process I never posted. If they're helpful I'll send them to anyone who wants them or perhaps I can post them to the wiki if I could figure out how to.

Another thought on the Minolta modification is if you replaced that point contact switch with a potentiometer you just might have yourself a varible speed camera. Alas I long ago sold both of those cameras so I no longer have them to experiment with. Anyone have an XL 42 or 64 to try this with?......
Cheers,

I tried this on my XL 64 - followed the instructions closely - but I must have done something wrong as I now only have 24fps. Nevermind!