Why no sound in slow motion? at DVinfo.net

Swen Goebbels · March 4th, 2010, 11:43 PM

Hello together,

mostly I have to do my slowmotion in post production, because I need the sound also during the slowmo (so I have to film in 720p50/60). But we all know that this will not look as good as directly filmed in slowmotion mode. Just putting a 720p50 clip with sound in an 720p25 timeline is the same as directly to edit a 720p50 version and add a 50% slowmo in post.

So why can't the camera not just record the sound also during S&Q mode, for people who can't use an extern audio recorder? Technical I don't see a reason for this. The camera can record the sound first normal and then just make it as slow as it will fit in sync to the slowmo clip. Or just record the sound normal without over/undercranking and we sync the speed of each clip in post production. But really zero sound recording is not very helpfull. The datarate of the sound recording can't be the real reason for this.

That's something I would love to see in an Firmwareupdate!

Best wishes,
Swen

Shaughan Flynn · March 5th, 2010, 01:14 PM

So, you are over cranking and you want to hear slowed down audio as well???

Marty Welk · March 5th, 2010, 04:23 PM

i do.

Mabey they leave stuff like that out because the next complaint will be that it doesnt sound correct, or just because it would be even more data.

solution, provide CHOICE, audio or no, a simple selection in the S&Q menu or the audio menu. if the sound was there , the extra (video compression) data alone during an overcrank would do a different Compression rate, when the video was set back for the original frame capture rate, providing more than just "slow motion" for an overcrank. less compression :-) cool.

i say at least ALLOW it to exist, we will deal with the problems that causes if we wish to apply it in some way. Slow audio is almost as cool as slow video.

we have an old vhs machine here that will even play a VHSs audio correct with slowdowns and speedups by using a buffer and adjusted sampling, if they could do it in a $400 vhs machine, then not only could they have had sound, but they could subsample (or whatever) and have it be slow sounding or normal sounding too.

Greg Chisholm · March 5th, 2010, 06:01 PM

you could slow it down in soundtrackpro.

Greg

Walter Brokx · March 5th, 2010, 07:08 PM

Well, it's a good question (and a good request: I got one as well: combine cache and overcranking. That would be great for (fighting)sports).
It's a lot easier syncing slowmo in musicvideos when the sound is recorded as well.

I'm curious this can be 'fixed' with an update...

Swen Goebbels · March 7th, 2010, 03:43 AM

Quote:

Originally Posted by Shaughan Flynn

So, you are over cranking and you want to hear slowed down audio as well???

Exactly, as Marty wrote here "Slow audio is almost as cool as slow video." A big V8 engine on a Pro Truck offroad race, a car crash, machine gun... all those stuff looks way better in slow motion when you have the real sound which belongs to the clip. When you just put music on the clip without any real backgroundsound it'll never touch the viewer as much as with real sound in my opinion.

Quote:

solution, provide CHOICE, audio or no, a simple selection in the S&Q menu or the audio menu. if the sound was there , the extra (video compression) data alone during an overcrank would do a different Compression rate, when the video was set back for the original frame capture rate, providing more than just "slow motion" for an overcrank. less compression :-) cool.

i say at least ALLOW it to exist, we will deal with the problems that causes if we wish to apply it in some way. Slow audio is almost as cool as slow video.

This is a great idea, I really hope Sony could add this to a firmware update or at least to the next generations of their camcorders.

Quote:

you could slow it down in soundtrackpro.

That can't be the solution, because there will no sound be captured when you use the S&Q mode. And slowmotion in post doesn't look as great as filmed directly in the camera.

Olof Ekbergh · March 7th, 2010, 06:32 PM

Why not just use an external recorder and use a clapper in the beginning of the take and in the end of the take. Then you can match it up perfectly in post.
I would use a 96/24 or 192/24 capable recorder or higher so when you slow it down you don't loose audio quality.

I think this is one of the reasons why Sony does not include audio in over crank, you need a completely different audio board than a standard 48/16. And they are not cheap if they are any good.

It would also have to be able to retime to write the audio file, this is complex as well some times you may do 38 fps other times 56 or 60. You can only do so much in an inexpensive (sub 10,000) camera.

If you are shooting sports or races etc. You can probably achieve the same result with some foley work, based on a high quality audio recording at the same venue even if it is not locked in time code.

Marty Welk · March 7th, 2010, 06:46 PM

that is probably it. its not the 1/2 or 2x that they could do easily in an internal processing, but "everything in between" too.

March 4th, 2010, 11:43 PM	#1
Swen Goebbels Regular Crew Join Date: Dec 2007 Location: Aachen, Germany and Las Vegas NV Posts: 107	Why no sound in slow motion? Hello together, mostly I have to do my slowmotion in post production, because I need the sound also during the slowmo (so I have to film in 720p50/60). But we all know that this will not look as good as directly filmed in slowmotion mode. Just putting a 720p50 clip with sound in an 720p25 timeline is the same as directly to edit a 720p50 version and add a 50% slowmo in post. So why can't the camera not just record the sound also during S&Q mode, for people who can't use an extern audio recorder? Technical I don't see a reason for this. The camera can record the sound first normal and then just make it as slow as it will fit in sync to the slowmo clip. Or just record the sound normal without over/undercranking and we sync the speed of each clip in post production. But really zero sound recording is not very helpfull. The datarate of the sound recording can't be the real reason for this. That's something I would love to see in an Firmwareupdate! Best wishes, Swen Last edited by Swen Goebbels; March 5th, 2010 at 01:14 AM.

March 5th, 2010, 01:14 PM	#2
Shaughan Flynn Major Player Join Date: Aug 2005 Posts: 272	So, you are over cranking and you want to hear slowed down audio as well??? __________________ B-Scene Films

March 5th, 2010, 04:23 PM	#3
Marty Welk Major Player Join Date: Sep 2008 Location: East Bay Cali Posts: 563	i do. Mabey they leave stuff like that out because the next complaint will be that it doesnt sound correct, or just because it would be even more data. solution, provide CHOICE, audio or no, a simple selection in the S&Q menu or the audio menu. if the sound was there , the extra (video compression) data alone during an overcrank would do a different Compression rate, when the video was set back for the original frame capture rate, providing more than just "slow motion" for an overcrank. less compression :-) cool. i say at least ALLOW it to exist, we will deal with the problems that causes if we wish to apply it in some way. Slow audio is almost as cool as slow video. we have an old vhs machine here that will even play a VHSs audio correct with slowdowns and speedups by using a buffer and adjusted sampling, if they could do it in a $400 vhs machine, then not only could they have had sound, but they could subsample (or whatever) and have it be slow sounding or normal sounding too. __________________ ----------------sig----------------- Re-learning everything all over again, one more time.

March 5th, 2010, 07:08 PM	#5
Walter Brokx Major Player Join Date: Jan 2010 Location: Maassluis, The Netherlands Posts: 294	Well, it's a good question (and a good request: I got one as well: combine cache and overcranking. That would be great for (fighting)sports). It's a lot easier syncing slowmo in musicvideos when the sound is recorded as well. I'm curious this can be 'fixed' with an update... __________________ Brainstormnavigator searching for the hole in the sky..... Audiovisual Designer (NL) - http://www.brokxmedia.nl

March 7th, 2010, 06:46 PM	#8
Marty Welk Major Player Join Date: Sep 2008 Location: East Bay Cali Posts: 563	that is probably it. its not the 1/2 or 2x that they could do easily in an internal processing, but "everything in between" too. __________________ ----------------sig----------------- Re-learning everything all over again, one more time.

March 5th, 2010, 06:01 PM	#4
Greg Chisholm Major Player Join Date: Aug 2008 Location: Jersey City, NJ Posts: 244	you could slow it down in soundtrackpro. Greg

March 7th, 2010, 06:32 PM	#7
Olof Ekbergh Sponsor: Westside AV Join Date: Dec 2008 Location: Mount Washington Valley, NH, USA Posts: 1,365	Why not just use an external recorder and use a clapper in the beginning of the take and in the end of the take. Then you can match it up perfectly in post. I would use a 96/24 or 192/24 capable recorder or higher so when you slow it down you don't loose audio quality. I think this is one of the reasons why Sony does not include audio in over crank, you need a completely different audio board than a standard 48/16. And they are not cheap if they are any good. It would also have to be able to retime to write the audio file, this is complex as well some times you may do 38 fps other times 56 or 60. You can only do so much in an inexpensive (sub 10,000) camera. If you are shooting sports or races etc. You can probably achieve the same result with some foley work, based on a high quality audio recording at the same venue even if it is not locked in time code.