Sound synch problem, help!

[ROKOKO]

this happens every so often i capture my dvx footage to my mac FCP. I use 24PA and capture using advanced pulldown removal and then use a 24 p timeline anamorphic.

the thing is, sometimes the sound is either completely out of synch (usually early as all hell) or slightly early where you may not notice it. When I then move the sound one frame late, it is in synch.

I heard about a sound synch problem on the original dvx100 but i have a dvx100b and this does not always happen. What is going on??? I'm working on an extrememly important project and this is worrying me a lot.

Another odd thing i'm seeing which MAY be normal is a flickering (like shutter effect) of the screen in my footage when playing back. Is this normal and endemic of true 24 fps footage or is something the matter. It's like a pulsing/shuttering most noticeable on plain white or light walls in the background or big sections of solid colour.

mainly though, the sound thing is the concern above all.

thanks...

 

[Eon42]

Well, with the DVX100A and DVX100B I've heard that a "audio buffer" system was developed to help prevent common problems with audio synch. I think it only helped a little bit - If my memory serves me, I believe that this audio synch problem is very common when shooting in 24P, and it can easily be fixed in post. As for that infamous "shutter effect", are you panning quickly? If so, it will flicker, and you'll have to either:

A) Keep camera following a subject (ie, a person) so the "background" shuttering isn't so noticable. (Since the focal point is the subject, people tend to pay less attention to the background.)
B) Make slower pans. Smoother pans will decrease the shutter effect.
C) Change shutter speed. (I shoot 1/43, I don't know if that's the best but you usually have to adjust it according to your lighting anyways. If you change it from, lets say, 1/48 to 1/43 or 1/40 - the shutter effect will blur a little. This may be the kind of thing you're looking for.
Or D) Do all of the above in conjuntion with eachother.

I'm probably telling you a bunch of stuff you already know. I decided to just take a stab at it. Are you playing back on an Interlaced device or a Progressive Scan device? Also, if you're filming a computer screen or something, change your shutter speed to 1/60, this helps a lot.

- Hope I didn't ramble you to death. I'm just explaining what I've been learning.

-Eon42

 

[ROKOKO]

thanks a lot man. good stuff. yeah i do pan slowly and the shuttering is from the backgrounds and so on even when static. it may just be the way it is i guess.

i play back on interlaced tvs (dont have a pro scan tv) however i use a Playstation 2 dvd player to watch my 24p dvd's and thats a pro scan dvd player i believe. not certain. but yeah tvs are all regular interlaced.

the sound thing i think may be the firewire cord or connector issue with my old dv cam i was using for capture. i am now using my dvx for capturing to my mac. Hope it doesn't have the same issues.

hmmm...