Crystal sync?

[Ian]

Can someone explain what crystal sync is?

Thanks

Ian

[S8 Booster]

check outSOUNDin the grey menu bar under the logo of this site for more.

Crystal sync

This system is based on two crystals which works together like two identical clocks. One regulates the speed of the camera while the other works with the sound recorder. Visit the Film Group's website for more information.
This was just the very basics about sound and super8. Now it's your turn to try it out and remember to use a clapper! Good luck!

Also: http://www.super8mm.org/field_recorders.html

Some cameras like Canons 814/1014 XL-S in normal healthy working condition are reported to run sync within 1 frame or so over a 15m cart without need for X-tal syncing due to its built in oscillator speed reference.

Some Nizos seem to do this as well as possibly some other Canon models. Verification tests required for each cam though.

R

[mattias]

Some cameras like Canons 814/1014 XL-S in normal healthy working condition are reported to run sync within 1 frame or so over a 15m cart without need for X-tal syncing due to its built in oscillator speed reference.

they run at a steady, constant, but not "exact" speed. my canon 814e runs at something like 23.5 fps, meaning i have to speed up my audio by 6% instead of the usual 4.2% to achieve sync after transferring to pal video. you'll have to experiment to find the speed of yours, but you can generally count on this speed staying constant at least for the duration of one shoot.

/matt

[S8 Booster]

True but factual tests done with the XL-Ss shows deviation no more than +/- 1 frame vs x-tal synced recorders. From ACS board - reference posted earlier.

R

[S8 Booster]

Another one:

So long as your clips aren't more than 20 seconds each (highly unlikely) then just shoot it! Crystal Sync is cool, but your Canon is possibly THEE most steady speed camera without a crystal sync. People have tested them to fluctuate about a frame per minute. Connect a multimeter to the flash socket on the camera and see if it produce 24.00 htz You might be quite surprised. Check out old posts here by searching Crystal Sync - all the info is here and this is the best site to find it...

I saw one demo-film at Finnish 8 mm meeting (7.9.2002).

That guy has shot the whole K40 roll and at the same time recorded the sound with dat-recorded. The camera was Canon 1014 XL-S without crystal sync. He had striped super 8 roll and managed to get that sound track keeping it sync the whole time (2,4 minutes)!

R

[mattias]

True but factual tests

true factual tests performed by myself also show that it depends on the exact model and condition of the camera (i've tried all but the 1014xls which i sadly haven't been able to get my hands on). as long as your canon is an electronic or xls you can count on it to be very steady in speed, but only if you're lucky is this speed exactly 24.00 fps.

/matt

[S8 Booster]

True but factual tests

true factual tests performed by myself also show that it depends on the exact model and condition of the camera

/matt

True - always has to be verified with each cam.

.... but only if you're lucky is this speed exactly 24.00 fps.

/matt

Actually if anybody bothered to do a thorough job on the XL-S the "clock" frequency is adjustable and with a scope it is possible to set the oscillator spot on. Using this as a speed/sync reference both motors are digitally controlled through the CPU and synced/balanced individually and together.

The cam also implements (I seem to recall ) independant 2 constant voltage most likly DC/DC powersupplies which keeps the voltage constant to the control systems and keeps the system/cam performance constant as long as the batts can supply power independant of the voltage dropping.

In short for Super8ing 15,25 meter carts it should do the most.

R

[Ian_]

So crystal sync would come stock on a 1014 xls. This is not a modifcation made to to the camera?

Thank

[S8 Booster]

No - it is not X-tal synced but use a pretty accurate and adjustabe LC oscillator which generates a master clock frequency allowing the camera a very good stability and close to X-tal accuracy for a 50´cartridge.

A camera in good condition and verified OK will not need x-tal syncing.

The same applies to some Nizos - my guess it the later 6080 & 4080s

R

[S8 Booster]

Regarding the Canon - currently a curiosity:

It is actually failry easy to convert the 1014/814 X models to true X-tal sync. A Xtal oscillator + some downcalc ICs to the correct reference at 1048 Hz or so and implement it to the control circuit points disconnecting the original one.

I believe it will cost less than 1 Euro in parts and may possibly be placed inside the cam. This x-tal sync would serve all speeds 9-18-24 but if I remember correctly the 36fps.

R

[FourFourForty]

Here's something I've wondered about from time to time:

Assume one has a cam that holds a constant fps, but not 24fps, perhaps 23.65 or some other non-conventional speed. A roll or two of film is shot and sent away for processing and transfer. At what speed is the film transferred to video for editing (NLE) and what is the best way to calculate the correction to 24fps (or downward-adjust the 29.97fps standard video speed) and sync the audio?

I hope my question is stated clearly. It's still quite early here.

[mattias]

23.976 fps, as always, or 25fps for pal. the percentage to change the audio can be calculated *if* you know the exact framerate, but it's easier to just experiment with one take until it syncs up and then apply the same percentage to the rest.

/matt