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on-camera hypercarioid X/Y to reject op's noises?


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Hi everyone, this is my very first post here, and I'm honored to ask for your help about a question:
As a filmaking student I havo to make a little documentary with audio 5.1.
The bad thing about audio is that I'm completely alone (I haven't a boom guy).
The good thing is that this documentary will be almost without dialogues (it's a sort of silent and poetic tale about the life of an old woman).
In this scenario I thought to realize the surround audio field completely in post, mixing different sources taken during "clean" off-camera sessions (so avoiding to capture audio during video sessions) and this for 2 reasons:
1. creating an imaginary (and perhaps more interesting) sound landscape;
2. basically avoiding to capture my noises as camera operator (my steps, my breath, steady squeaking) during video takes.
Recreating a fictitious audio in post should work for all the channels BUT one: the C-channel, that contains the most "in-frame" audio effects: infact I can't dub my talent's own steps, movements' noises, sighs, etc. (because she's not an actor, but a real woman living her life). In few words I need at least an on-camera mic solution to capture the C-channel effects.
The problem is: which mic is able to bring only the sounds on its front while completely rejecting the sounds on its rear? If you know a mic like this, please tell me! Because up to now all the polar diagrams I've seen show a certain capsule's sensibility also under the center:
a) omni is obviously unusable for my purpose;
B) cardiod has two curves under the center, and tends to behave like omni at low frequencies;
c) hypercardioid have a little ball of sensibility on its rear;
d) shotgun is narrow but creates a sort of 8 figure in its diagram, i.e. it captures also on the back.
Surely shotgun is fine as boom mic, or even as on-camera mic if the operator is moveless and silent, but in a run&gun scenario I can't think it's the right mean to capture a clean audio. And more than this, it's too directional for a moving talent in a on-camera condition.
Someone uses all-in-one solutions like the fantastic Sony PCM-D100 mounted on the camera: I've thought about it, but I've heard tests with evident camera-operator's noises (and all this recorders have internal little capsules that are unidirectioal only at 1kHz and up, but under 1kHz the capsules behave like omni).
So does exist an on-camera mic solution to capture front-only?
I have an hypothesis that I'd need to discuss with you:
Let say I'd start with an hypercardioid because it should work indoor (without too much reverb) and basically also outdoor. I'd choose a mic with a pretty constant polar diagram for all the frequency spectrum (Audio-Tachnica AT4053B, or Audix SCX1-HC, or a modified Oktava MK012) and I'd use two in X/Y position on the camera (so I should choose a mic without handling issues). In this way I'll surely capture front + side + rear sounds, it's true, but there should be only a single common cross-diagrams portion, and that portion should be only in front of the camera, not in the back nor on the side. This "clean" portion should be obtained by algebrical operation on the two channels (in a DAW), and it should be my C-channel.
Do you think it could work?
I'd use a Tascam DR-70D (screwed under the camera) modified by Busman to have very clean preamp, and a couple of AT4053B or SCX1hc mounted over the camera in X/Y position. I've read that modified Oktavas are very interesting but I've also read that they are too sensitive to operator's movements. So, between AT4053B and SCX1hc, which is in your opinion the less problematic in a run&gun scenario?

Thanks for all your help (I really need it) and your advices.

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1 hour ago, adrjork said:

The problem is: which mic is able to bring only the sounds on its front while completely rejecting the sounds on its rear?

this is a common beginners desire - short story is it doesn't exist.

your best bet is probably just to capture audio only bits and pieces in between (possibly very close), then sculpt your sound scape ignoring reality. that sometimes can result in a poetic feeling if done with care, imagination and love.

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9 minutes ago, chrismedr said:

your best bet is probably just to capture audio only bits and pieces in between (possibly very close), then sculpt your sound scape ignoring reality. that sometimes can result in a poetic feeling if done with care, imagination and love.

Thanks for your reply. So you don't think the algebrical solution from the 2 hypercardioids could work. Then, following your advice, which device do you recommend?
Thanks

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It seems like you're complicating it too much.

For your situation, a simple on camera shotgun like a Rode VideoMic might work fine. Even better, the Shure Lenshopper VP83F has an onboard microSD recorder and you can also send a backup to the camera.

You can do some basic things to cut down on the noise that you are making with footsteps and such. If it's inside, take off your shoes, don't wear noisy materials, etc.

Hope that helps.

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Hi,

I will suggest you a different forum, the Gearslutz.

You build a 5.1 mix in post production, not in location.

Make your life easier and use a microphone like Ambient TinyMike.

Ask a supervising sound editor / sound designer about stereo recording techniques; how translated in 5.1.

Have fun!

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Hi adryork (perhaps an unfortunate name for a predominately production sound recordist forum!?!),

You (as all of us) are going to learn (and continue to learn) by doing. So choose between a hypercardiod and a short shotgun for the camera and start filming.

If you want to get experimental beyond your experience rig an MSM (chosen C mic plus a fig 8 and a backwards cardioid) to the camera. But I suggest you don't, and just choose a mono mic and concentrate on two things - the filmmaking (storytelling etc) and keeping an eye open for technical improvement.

Best of luck, and as Cocteau said (in some character's words),

"astonish us"

Cheers, Jez Adamson

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5 hours ago, adrjork said:

I can't dub my talent's own steps, movements' noises, sighs, etc. (because she's not an actor, but a real woman living her life).

Why can't you? This is what a Foley artist does. A Foley artist can do this a lot better than you could capture on set. 

Get a decent shotgun mounted on camera, be quiet while you're shooting, and get what you can. Then do the rest in post. 

-Mike

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5 hours ago, adrjork said:

Let say I'd start with an hypercardioid because it should work indoor (without too much reverb) and basically also outdoor. I'd choose a mic with a pretty constant polar diagram for all the frequency spectrum (Audio-Tachnica AT4053B, or Audix SCX1-HC, or a modified Oktava MK012) and I'd use two in X/Y position on the camera (so I should choose a mic without handling issues). In this way I'll surely capture front + side + rear sounds, it's true, but there should be only a single common cross-diagrams portion, and that portion should be only in front of the camera, not in the back nor on the side. This "clean" portion should be obtained by algebrical operation on the two channels (in a DAW), and it should be my C-channel.

And I've read and tried to understand what you're getting at here but I'm afraid I cannot picture it- and I'm a very boring person who thinks continuously about microphone positions, arrays and vectors ....

Mic types are actually pretty simple in theory: there's OMNI (pressure) and FIG 8 (velocity) and that's it.

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9 hours ago, josephboyle said:

For your situation, a simple on camera shotgun like a Rode VideoMic might work fine. Even better, the Shure Lenshopper VP83F has an onboard microSD recorder and you can also send a backup to the camera.

Yes, the Shure VP83F Lenshopper was my first thought, and it has a pretty decent polar diagram, it's more an hyper than a shotgun, and it has also a decent S/N ratio. And the flash recording option is important (to avoid the bad preamp of the camera itself).

6 hours ago, Mobilemike said:

A Foley artist can do this a lot better than you could capture on set.

It's true but unfortunately I'm not a foley artist, and as I've written before, I'm alone in this project, so I have to stand on my own two feet :)

First of all, thank you all for your advices and your help.
Anyway, just for curiosity, anyone can tell me which is in your opinion the less problematic mic for outdoor handling movements between AT4053B, SCX1hc and modified MK012?

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2 minutes ago, mikewest said:

Did a test years ago for a producer and discovered that a half decent short shotgun

mounted on the camera worked so well with the lens size and typical shots

Thanks a lot Mike. Then I'll probably go for the Shure VP83F Lenshopper recommended by josephboyle.

Anyway, just for my knowledge, anyone knows if there is a way to apply an operation, in post, to a 2-channel stereo track in order to obtain the only recorded space in common? (For example: L records both left and center, R records both R and center; I'd like to apply an operation to obtain the common center part from both channels.)

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5 hours ago, adrjork said:

Yes, the Shure VP83F Lenshopper was my first thought, and it has a pretty decent polar diagram, it's more an hyper than a shotgun, and it has also a decent S/N ratio. And the flash recording option is important (to avoid the bad preamp of the camera itself).

Someone should let Shure know about that so they can update their website...

Screen Shot 2017-06-07 at 8.53.43 AM.png

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You have answered yourself, young Skywalker. Post. where even sounds recorded in stereo can be folded down to mono. Where discrete sound effects can be panned to the center. Smile and know that you know more than you know.

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I'd stay away from 5:1 altogether, unless you're an experienced post-mixer and can check out the venue for playback a head of time. I heard one filmmakers 5:1 mix that down mixed only the rear channels when playback on a conventional two channel system. I've attended and read about of many film festivals and such that were multi-channel nightmares. Even a professorially mixed program's audio can get butchered.

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Have you thought about putting a boom and mic on a sand-bagged C-stand? That's what a lot of us do for one-man-band interview stuff, I don't see why it can't work for what you're doing as long as you don't need to do a lot of walking around and changing frame. It gets the mic far away from the camera and operator noise and much closer to your subject so you can capture those poetic nuances.

Just food for thought, I wish I'd thought about it when I was debating what on-camera mic to get years ago. The short of it is, any on camera mic will be serviceable if you're careful not to make make noise yourself, but getting a mono mic close to your subject and away from the camera is almost always the best option. That's what most of us here are paid to do and that's why it often sounds so much better.


Sent from my iPhone using Tapatalk

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Thank you all for your advices. I'm very honored of receiving your replies.
I'll take a time to think about what to buy.

(I'll do some tests with the poor means I own at the moment. If I'll obtain something interesting, I'll surely post my impressions here.)

Anyway, someone of you have experience about booming or handling AT4053B vs SCX1hc vs modified MK012? Anyone can say which is the less problematic in moving situation?

And (perhaps this could seem a bit topic-off) let try to forget the camera: what mic do you recommend for ambient noises recording? Infact, as I described the kind of sounds I'd like to capture from the old lady (sighs, steps, almost no words, etc.) these could be considered like ambient sounds, right? So, if I decide to capture all AWAY from the camera, the hyper (like AT4053B or similar) could be still a good choice? I've read a lot of people preferring something like DPA4060 (little omni) for field recording, but I have the suspect that perhaps - for the kind of sounds I'd need to capture - something like the AT4053B could be more flexible. (If possible I'd like something able to capture little specific sounds - as I said sighs, etc. - but also a field situation, is it possible? I've read for example that someone does all with the Sony PCM D100: both field and near sounds). So what is your advices? An hypercardioid could be the flexible solution for all the days? Or the Sony? Or something else?

Really thanks as always.

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The Oktava 012 is very susceptible to air turbulence and handling noise. It also has a low sensitivity spec (10mV). By comparison, the Sennheiser and AT hypers are in the 21-25mV range. I would not recommend the Oktava for camera mount usage.. modded or not. Of coarse no cam mounted mic is going to sound very good. Aside from 'nat sound'.

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I use Oktavas on cameras all the time and they work quite well.  You need a decent mount for them, and having the in-line low rolloff helps too.  They sound pretty good, are cheap (look around on Ebay or CL) and are small,  all good things with today's dinky cameras.  As with most on-camera mics, the biggest issue is wind protection vs keeping same out of the shot.   

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