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Whats the matter here?


stephenbyron

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I just returned from seeing a rough cut of a music "video" I'm putting together with a friend and we're both baffled that the footage seems to be speeding up in spots.

It was shot with a canon 310xl (18fps), transferred professionally and then imported into final cut.

i contacted the transfer house before i sent it and they assured me that the transfer would not change the speed of the film. I'm wondering if I have to use some specific frame rate when i import into final cut? I think it was brought in @ 29.97fps.

My friend thinks it may be the camera because after shooting the video she took the camera to Asia and the footage (after transferring at a different transfer lab) seems sped up as well.

But, I don't notice a change in exposure ? If the film was moving through the camera at different speeds wouldn't I notice a change in exposure?

Thanks to all.

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Stephen, when you shoot Super 8 for sound sync, you need three things. 1) You need to have a camera set to shoot at 24fps. 2) You need your camera to be crystal synced so it goes a constant speed. 3) You need a digital audio recorder for the sound OR you need a NAGRA or stereo recorder that are also crystal synced.

 

The OTHER method to sync sound is:

 

1) Shoot 24fps on a camera that has a PULSE SYNC output OR has a PC contact with a pilotone to digital converter. 2) Hook your PULSE SYNC output or pilotone to digital converter to a NAGRA or stereo recorder while recording sound. 3) Have a lab resolve your soundtrack with your film based on the pilotone track (which will vary since your camera isnt crystal synced.)

 

Just remember, just because a camera has a setting of 18fps, 24fps, etc that is only a general ballpark. This is by no means a constant speed. A crystal motor is the ONLY way to ensure your speed is constant down to a ridiculously small margin of error.

 

I hope this clarifies your problem.

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18fps, also would produce sped up footage when telecined out to video, as normal speed is 24fps, hence the speed chance.

As for the exposure, if you exposed properly on the camera, then it wouldn't change just because it's now sped up. So if you meteres @18fps, then your exposure would be correct.

 

 

and I was beaten to my point! Damn now I sound like an echo.

Edited by Adrian Sierkowski
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just semantics it seems,

back to the problem @ hand, perhaps try slowing the footage down a bit in your NLE?

I'm not sure, exactly, the % diff between 18 and 24fps, and I not the best at math, but just tweak 'round with it till it seems to sync up a bit.

Conversely, you could speed up the audio, and then export it @18fps in theory?

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just semantics it seems,

back to the problem @ hand, perhaps try slowing the footage down a bit in your NLE?

I'm not sure, exactly, the % diff between 18 and 24fps, and I not the best at math, but just tweak 'round with it till it seems to sync up a bit.

Conversely, you could speed up the audio, and then export it @18fps in theory?

 

The best route would be, like Adrian said, to slow the footage down to the speed it was when you shot it. Consequently, like he also said, you could just speed your audio up but this will 1) look funny since your picture is sped up and 2) Cause a pitch change due to increasing the speed of the audio. I would recommend option #1.

 

The mathematics for the slow down are: if(18/100 = 24/x) then SlowDownPercentage= x-100 which would be 33 1/3 % slow down. This is based off of 18fps being 100% of the natural frame rate equaling 24 fps being x percentage of the natural frame rate as a reference. Therefore, you discover that 24fps transfer is 133 1/3% faster what the 18fps was supposed to be. Did that make since?

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As per audio pitch, you can mess with that, if you go the audio speed up rate, in a program like ProTools where you cna catch the pitch w/o affecting speed (used it to make a Mr Moviephone voice once).

 

 

See, that math is why the American Cinematographer's Manual is such a nice buY!

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See, that math is why the American Cinematographer's Manual is such a nice buY!

 

Ok, I feel silly because I realize I totally over complicated that. It's really as easy as 24/18 and you still get the same result.

 

ie [(24/18)-1] * 100 = %Slowdown

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Double-check with the transfer house because on some systems 18fps footage has to be ramped up to 20fps to avoid flicker.

 

In the future you could also try this: do a head slate (clapper) AND a tail slate (at the end of the of each shot). Once on your computer it is easy to measure speed change from head to tail and then perform the precise speed correction on the footage.

 

Rick

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Thanks to all for the info.

 

I think maybe I should call the transfer place back and ask them why they said it would be "no problem" and everything would be in sync?

I figured it would drift some, but i thought In editing i could line things back up and avoid parts that were way out (creative editing!)

I'm going to try slowing it down and hope its close enought to work with.

 

Also, I just bought a Beaulieu 4008ZM2. I know this shoots @ 24fps, but is it crystal sync speed?

I don't think it is.

Any idea how I would sync up for a music "video" or sound with this camera?

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Also, I just bought a Beaulieu 4008ZM2. I know this shoots @ 24fps, but is it crystal sync speed?

I don't think it is.

Any idea how I would sync up for a music "video" or sound with this camera?

 

24fps is the right speed but you wont be guaranteed a constant speed unless you get a crystal sync unit for the camera through The film group (http://users.aol.com/fmgp) will crystal sync it for $500.

 

If you choose not to go the crystal sync route, you can try just setting it to 24fps and hoping for the best. I've never tried this method with a Beaulieu 4008 but the general average that people have success with is keeping their shots under a minute and results are best at 30 seconds or less. The longer your shot, the more likely it will drift and be detectable. When you consider that a roll of S8 film is only 2.5 minutes @ 24fps anyway, I cant imagine people want to use a whole roll on one shot. If you do want to do that, however, you MUST use crystal sync as no S8 camera that's not synced is that constant.

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Hi Stephen,

just to re-cap on the above:

 

If the telecine house has a flying spot type scanner of one sort or another (as most professional houses do) then if they said 18 was o.k. they will have added fields or frames to make it so. The problem isn't with the telecine transfer. If it was some other more basic transfer that didn't work a frame at a time then it will probably be 20 fps. But the 20fps type devices do a much poorer quality job. Its unlikely you would have used one for a music video.

 

Yes, its the camera speed. No, no super 8 cameras were manufactured with crystal speed control. Yes, you can have it added to some cameras.

No, its not absolutely necessary if you do as Rick said.

 

Of course, being a music video, you don't want to mess with the duration of the audio (as you might have if it was a 'drama' film). So you have to tweak the picture duration. This will need to be done shot by shot I am afraid. And you have to do it by eye. Sliding and stretching each shot until it looks correct. Can be done.

 

good luck with it.

richard

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No, no super 8 cameras were manufactured with crystal speed control. Yes, you can have it added to some cameras.

 

Well, actually the Beaulieu 9008 Quartz was crystal synced but you're right that it is rare for S8.

 

I didn't realize that Stephen was using a lower end transfer service so I was only guessing why his footage wouldn't sync. I assumed he used a professional RANK transfer house like Spectra or Pro8mm. Those places transfer at 24fps unless you specify 18fps and pay extra.

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But the 20fps type devices do a much poorer quality job.

richard

 

That's too general of a statement for me to accept. Old-school film-chain set-ups need to ramp to 20fps to avoid flicker, but many of these set-ups are good. Our feature Sleep Always was transferred this way and while it is not the best transfer possible it is not anywhere near "poor quality".

 

Rick

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seems to be speeding up in spots

 

...hmm, re-reading the OP, this almost reads as if the camera would speed up occassionally rather then constantly, which is what we pressumed througout this thread... now if that were the case, then the issue would not be telecine as was rightly argued for constant speeding up, but a transportation issue related to tired transport mechanics in the camera or frictional problems from the Super 8 cartridge (what film stocks were used from which supplier?). That would also explain the OPosters question re. a change in exposure what he rightly believes could be noticable with changes of the filming speed.

 

If the film was moving through the camera at different speeds wouldn't I notice a change in exposure?

 

As the Canon 310 XL is build around an automatic exposure control system with just two flying f-stop adjustments up and down, this wouldn't be the case. In order to see differences in exposure, you would need to have a fixed f-stop setting ? your camera would automatically compensate for changes in the filming speed. Unless the automatic exposure control system is constructed in such a way, that the electic eye wiring and electric regulation would not recognise the required compensation when the filming speed changes. As the Canon 310 XL is one of the few cameras that only features 18fps and isn't TTL, that might be the case. The Canon III XL is a similar design and reacts like that.

 

Just a different angle as I kinda read the OP differently... probably just me ;) ...

 

the general average that people have success with is keeping their shots under a minute and results are best at 30 seconds or less. The longer your shot, the more likely it will drift and be detectable.

 

I was once forced to shoot some interview sequences (yes, no joke!) in unquartzed sepmag. 8 seconds is the absolute maximum you can get in-sync until you get drift-offs and will have to re-set the audio and film tracks in either your NLE system or on a Super 8 Schmid or Steenbeck.

 

BTW, the Beaulieu 9008 Quartz-series is indeed the only Super 8 camera ever offered with a built-in crystal-sync module, however, this was essentially Ritter/Beaulieu-in-Germany moving a previous optional accessory for the Beaulieu 6/7/9008-series into this last special model of which only few more than a dozen were built. So in comparison, many more Super 8 cameras, especially the Beaulieu 4008-series, were delivered by customer-demand with built-in or add-on crystal sync units than of the Beaulieu 9008 Quartz-model were ever built in the factory.

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I was once forced to shoot some interview sequences (yes, no joke!) in unquartzed sepmag. 8 seconds is the absolute maximum you can get in-sync until you get drift-offs and will have to re-set the audio and film tracks in either your NLE system or on a Super 8 Schmid or Steenbeck.

 

What camera were you using??? I dont understand what a "sepmag" is? I don't know if all cameras are able to keep a moderately constant speed. I know I had pretty good success with my Sankyo 620-XL. I don't know how your setup was either. I always shot at 24fps, recorded the audio on digital field recorder, telecined the film @ 24fps, uploaded my audio and slowed it very slightly to match the 29.97fps of NTSC. And I had my telecine put on MiniDV.

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What camera were you using???

 

Freshly CLA'd Beaulieu 4008 ZM II and equally out-of-workshop Nizo 2065 sound, which is known to have pretty good filming speed accuracy.

 

 

 

I dont understand what a "sepmag" is?

 

Commag and Sepmag are the terms for (one one hand) direct sound recording onto a commag sound stripe (as found in the Super 8 format in shape of the Ektasound cartridge, read more here), and on the other hand, recording the sound on a separate magnetic medium, i.e. mostly 1/4"-tape on a Nagra or Uher or Stellavox or Sony or Tascam or Bröker or Fostex...

 

I don't know if all cameras are able to keep a moderately constant speed.

 

High-end and top-of-the-market cameras do if they receive regular attention. However, if you do lip-sync, there is only so much two or at least one unregulated track will stay close to the sync'ing point.

 

I don't know how your setup was either.

 

Camera as above on a Linhof fluid support, mics were Sennheiser on Rycote rig, frame composition for classic interview portraits (nothing fancy with mouth 110° turned away in two of the three dimension, or such :P ), black clapper board (those were the days) and audio was actually a crystal-sync'd unit (!), a Uher Report 4400 (a.k.a. Bröker S 204) using Split 16 tape with a light sensor-based controller (that regulates the crystal unit by doublechecking the speed with which the Split 16 perfs are transported.

 

...

 

before anyone asks:

 

Split 16 were perforated 1/4"-tapes. There was also Super 8 perf'd 1/4"-tape. Note bene that the perfs were relative in their distance so that the 9.5cm/s or 19cm/s speeds of the tape machines were regulated in sync, and that the names had nothing really directly to do with 16mm or 8mm perfs on the cine-film (Split 16 perfs were just half the amount of Super 8 perfs, but the sizes were identical). Hence, you could use Split 16 or Super 8 for audio-recording to either Super 16 or Super 8.

 

All non-EBU-compliant island solutions, but many German broadcasting houses used these rigs up to the 1980s as less costly alternatives to Nagra and Stellavox (and Uher was widely used in radio broadcasting anyhow, where Nagras never got a strong foothold due to their prices). So these solutions weren't as outlandish as one might think reading this post.

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BTW, Uher systems and Schmid editing tables were also the set-up for the tv broadcasting houses in DACH using Super 8 film, i.e. during the short time Nizo professionals were used for news gathering and reportage in the late 1970s... documentaries remained Normal 16...; and then, of course, came U-matic and all this film-is-dead-baffoonery started... and kicks around to this day.

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Freshly CLA'd Beaulieu 4008 ZM II and equally out-of-workshop Nizo 2065 sound, which is known to have pretty good filming speed accuracy.

 

Well it doesn't seem like it had as good of speed accuracy as people think I presume? Maybe I can add this to my list of reasons why I think Beaulieu 4008 is overrated.

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