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Good evening gentlemen,
I have some concerns that I am greatly hoping you may be able to assist me with. I own a Beaulieu 4008ZM4. I also own a Sony TCD-D8 portable DAT recorder. I recently shot 4 rolls of "Pro8/74" (a 200 ASA color negative film stock provided by Super8Sound.) The purpose of my shooting these rolls was to make a short, test, sound film. The rolls were mainly interviews. I recorded the sound on the DAT and shot the rolls at 24fps. "shot the rolls at 24fps" means I simply set the camera's dial to 24fps. The camera is not crystal synched. I had Super8Sound transfer the rolls to regular 1/2" VHS, which they said would be transfered at "23.97fps." I also own an IMac, through which I edit my pictures. The sound and picture are not synching at all. The picture runs far too fast and the sound quickly falls behind. The failure to synch is quite drastic. To my limited knowledge I understand that if the film is shot at 24fps it should easily synch up with sound recorded through a DAT. I do not believe that the problem occurs when I import the picture into my computer for the image does not appear any faster than on the master tape that I watch through my VCR. Is the problem Super8Sound...probably not. Do you believe that the problem is my camera? I know it is old, but I didn't think that it would be that off. It looks as though it was shot at 18fps or something. Could it be one of the batteries? Would a bad battery cause for a lack of constant filming speed? I do not mind spending the money to have my camera crystal synched, but only if I am sure that the camera is the problem. Well, any suggestions or comments would be greatly appreciated and I patiently await your replies.
Thank you,
Tayman Strahorn.
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<BLOCKQUOTE><font size="1" face="Courier, Arial">quote:</font><HR>Originally posted by becomedeath:
The camera is not crystal synched.
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Well you pretty much answered your own question. If the camera is not crystal synchronized it will not run at exactly 24fps. Sounds like it's running a few frames faster.
If you plan on doing sounc sync filming you will need to eaither crystal sync the camera or find a way to sycn in post. That's one of big projects going on here on this message board. I think there is a Beaulieu pilotone generator for the 4008 cameras. But I don't think your dat would accept the generator. And even then I don't know where you would resolve your audio.
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Konton the Grey
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<BLOCKQUOTE><font size="1" face="Courier, Arial">quote:</font><HR>Originally posted by Konton:
Sounds like it's running a few frames faster.
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Actually, it sounds like the camera is running SLOWER than 24fps, since the transfer ended up increasing the final playback speed.
Roger
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Roger Evans
MovieStuff
http://www.afterimagephoto.tv/moviestuff.html
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two factors: 1) if the camera is not crystal, you will get drift. however, you should be able to sync short takes unless your cameras speed is way off. 2) you need to slow the sound down as much as the film! .01 percent. one tenth of one percent. do you have a drop frame/non-drop frame option on your computer? if not, you'll need to have the audio resolved down at a studio or sound lab. i have never shot a crystal spuer8 camera but i always am able to sync 1/2-3/4 of a roll. your camera must run at 24fps though and not 22 or 25....
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So even if I had the camera crystal synched through, say, the Film Group, it still would not synch up with sound recorded on a DAT in post production? I was under the impression that the camera would be synched alone and would not need to be connected to the audio equipment. But, as previously mentioned, my knowledge is quite limited.
Tayman Strahorn.
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it will sync. you need to slow the audio down, that's all. that is how it's done when working with digital. when they transfer the video, they slow it down. otherwise, if you were to edit with mag and film and regular speed, you would not need to do anything.
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So I can have the camera synched and continue recording sound with the DAT. How much will I need to slow the audio down? 1/10 of 1%? And if so, can I do that with just about any sound editing software? I patiently await your response.
Thank you,
tayman strahorn.
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Why do you have to slow the audio down? - I recorded sound on my minidisc recorder which synched perfectly with my footage (which was shot at a crystal synched 25fps -- and then both imported to the computer and matched up) and I have no idea what speed the minidsic was recording at? -- doesn't speed here (on the sound) effect the sampling rate - and it's not so much an issue what the sampling rate is - but just that it is perfectly regular and has no drift --- is this right or am I misunderstanding something here?
Scot M
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<BLOCKQUOTE><font size="1" face="Courier, Arial">quote:</font><HR>Originally posted by Scottness:
Why do you have to slow the audio down? - I recorded sound on my minidisc recorder which synched perfectly with my footage (which was shot at a crystal synched 25fps -- and then both imported to the computer and matched up)
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Hi, Scott!
You lucky bastards that shoot film and video at 25fps don't have to contend with the subtle speed difference that NTSC requires. In your country, film shot at 25fps will be transferred at 25fps. Here in NTSC land, film shot at 24fps will be transferred at 23.97, which is a tad slower. Therefore, the audio has to be slowed down a bit for longer takes, though shorter takes can generally work alright at 24fps audio speed.
Roger
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Roger Evans
MovieStuff
http://www.afterimagephoto.tv/moviestuff.html
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tayman: i am not the one to answer your computer questions. but here is a book i suggest you read: THE FILMMAKERS HANDBOOK a Comprehensive Guide for the Digital Age by S.Ascher & E.Pincus published by Plume. you should be able to get software. you may already have a program. how do you transfer your film to video? how do you import to the computer? i'll ask my editor.
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Thanks Roger that explains that - just coincidentally I was visited by someone this morning who has Beaulieu 7008Pro crytsal synched at 24fps by Super8Sound anyway the whole set up WAS GIVEN TO HIM by a friend! now that's good luck.....
Scot M
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Thank you gentlemen.
Tayman Strahorn
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One way to sync successful (frame accurate, not only tweaked) even with an old spring motor cameras is to take advantage of the flash socket and record the flash pulses (1 per frame) to one of the soundtracks, using a digital-to-1000 Hz-converter. This needs no camera modification.
In post prod you can either alighn each pulse to each frame, stretching and squeezing the audio manually. You will be able to "see" if the sound gets off or not.
Or, what I consider to be much better and less tricky, you use an AV audio player to input the audio into the computer and a synchronizer. AV means audio-vision and implements the possibility to access the running speed from external controls.
One sound track of your NLE you fill up with regular bursts of 1000 Hz, each lasting about half a frame. Then you playback the video, outputting this sync track over the audio card. The sync track will feed a synchronizer and the synchronizer will hook up the AV audio player to the speed of the sync track.
This will be done by comparing each sync track pulse and each camera pulse of the original audio. The speed will automatically be regulated in a way, that each singular pulse matches and the sync is perfect.
At the same time, the audio card must be able to record the audio to another track. This hardware setup helps a lot, is easy to handle and fully automatic, no "tweaking", even if the framerates are very off.
However, the sound quality will depend on the running characteristics of the camera.
Pedro
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> In post prod you can either alighn each pulse to each frame, stretching and squeezing the audio manually.
or you can do it automatically with my resolver software. sorry for not releasing it yet; i had planned to do it this week, but i've just been too busy. it's coming though.
/the other sales pitch guy
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Make sure you kep us posted on that Mattias (I know you will anyway) --- I might end up using it on my R16
Scot M
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