GH4 audio bug discovered

Is it known how the GH4 handles audio gain? For instance, if the gain control is analog, then the higher the gain the better the signal to noise ratio will be (because although there will be more noise, the signal will have increased by a larger amount). If it is digital gain, then the signal and preamp noise will be increased by the same amount. No point in using digital gain while recording because you could apply exactly the same digital gain in post production, under much more controlled circumstances.

Relevance to the topic is that if cranking up the gain is revealing the noise and it not providing more signal, then you might as well be recording at a lower level in any event and fixing in post production. And if recording at a lower level actually gives a better signal to noise ratio (in other words, the noise is reduced more than the signal is reduced) then there's something weird going on (for example, the digital gain process is itself adding noise, which could be firmware fixable).
 
Chadfish said:
Just turn off the limiter. You can totally turn that off on the GH4. There isn't the thing like on the Gh3 where you have different levels of limiting you set. You just have it off or on.
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...I want the Limiter, but NOT the AGC circuitry. So what I wish for is a separate switch to turn the AGC on or off. ( I would even pay to have the AGC permanently turned off, as long as I still had control over the limiter being on or off )
 
So my GH4 is on it's way back to the dealer :cry: ...
Perhaps in the future I'll re-purchase it in the GH4/YAGH kit (you save $400 that way vs. buying each separately).
 
It's normal for the audio track to have nose or hum when you have a device plugged in, but turned off on any camera. I can hear the noise on that shot of the kid.
 
Chadfish said:
It's normal for the audio track to have nose or hum when you have a device plugged in, but turned off on any camera.
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Perhaps noise or hum- but it shouldn't be both. My AF100, AC130A, HV30, DVC60 , and DVC80 all exhibit noticeable "white noise" with the gain turned up and a mic attached- but no hum or buzz.
 
Chadfish said:
It's normal for the audio track to have nose or hum when you have a device plugged in, but turned off on any camera. I can hear the noise on that shot of the kid.
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The mic is turned off to test for this issue just so that the buzz is more easily discernible. The buzz is present with the built-in mic as well, but you have to find a quiet room and cover the GH4's mics to block out as much external noise as possible. Plugging in an inactive mic is much simpler :)
 
Ed Kishel said:
So my GH4 is on it's way back to the dealer :cry: ...
Perhaps in the future I'll re-purchase it in the GH4/YAGH kit (you save $400 that way vs. buying each separately).
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Don't be sad and follow any option from these links:

http://www.bhphotovideo.com/c/product/907000-REG/Panasonic_dmw_ms2_External_Stereo_Mic_For.html

http://www.bhphotovideo.com/c/product/943375-REG/panasonic_vw_vms10_stereo_microphone_plug_in.html

http://www.bhphotovideo.com/c/product/929347-REG/tascam_dr_60d_4_ch_track_linear_pcm.html

"Auto tones can be added to the beginning and ending of the recording and a button can be pressed to add a slate tone to the audio at any time. These tones are also output to the 3.5mm camera out jack so they can be recorded to your DSLR camera's audio recorder for timing reference."
 
I knew about these panasonic mics- but they're overpriced IMO and I've got plenty of mics. My mics aren't the issue- my GH4's audio input was.
 
Ed Kishel said:
I knew about these panasonic mics- but they're overpriced IMO and I've got plenty of mics. My mics aren't the issue- my GH4's audio input was.
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But according to Panasonic, they work with no issue. Cheaper than YAGH for sure. If you say those branded mics are pricey, go figure about YAGH... ;-)

But, you're forgetting the plan B if we can call it B LOL Take a read in this post and thread and you'll find out the same viewpoint by other people (when different people say the same...) :

http://www.dvxuser.com/V6/showthrea...he-GH4&p=1986435176&viewfull=1#post1986435176
 
Emanuel- not to be a jerk here, but if Panasonic said "only Panasonic SDXC cards will work in the GH4, other cards may result in pixelated footage" or "only Panasonic made lenses will work with the GH4, other lenses may result in slightly blurry images" you might then understand where I'm coming from.

I'm not discarding all my other mics to buy new ones, or paying another 2k for an xlr adapter.
 
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Ed Kishel said:
Emanuel- not to be a jerk here, but if Panasonic said "only Panasonic SDXC cards will work in the GH4, other cards may result in pixelated footage" or "only Panasonic made lenses will work with the GH4, other lenses may result in slightly blurry images" you might then understand where I'm coming from.

I'm not discarding all my other mics to buy new ones, or paying another 2k for an xlr adapter.
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Your in your own. The point here is another one, though. This is not a marketing strategy, but a bug. Apparenty, their R&D homework guarantees their own mic gear will work. A plus, in the middle of the whole issue, in the end I guess. A more professional route is dual recording, anyway. At tiny fraction of the YAGH price. In any case, this is your post:

Ed Kishel said:
So my GH4 is on it's way back to the dealer :cry: ...
Perhaps in the future I'll re-purchase it in the GH4/YAGH kit (you save $400 that way vs. buying each separately).
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...so how can you say now you're not paying another 2k?! When you said exactly the opposite? You neither need to discard all your other mics because you add another one to your collection. I love contradictory stuff but my apologies on this one, because you are beyond me : D
 
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That's true, I did say that- but that's a perhaps, not a will (because with the mics I use, I may have no choice if I want to use them with this camera). Let me correct myself then- I certainly prefer not to.
 
Ed Kishel said:
That's true, I did say that- but that's a perhaps, not a will (because with the mics I use, I may have no choice if I want to use them with this camera). Let me correct myself then- I certainly prefer not to.
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Better to quit of the best camera for the buck ever than going with a 200 or 100 bucks mic or safer dual recording instead?
 
Emanuel said:
Better to quit of the best camera for the buck ever than going with a 200 or 100 bucks mic or safer dual recording instead?
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Yup, pretty much. I'm just that picky about sound I guess. The gh4 is indeed incredible, it's amazing how much camera Panasonic engineers have crammed into this tiny package. But it's the best bang for the buck right now. It's the "gotta have gear" right now. The 5D was there, the RED was there, the BMCC.... But there is always the future, and things move fast in the camera world. You have to be able to walk if it doesn't feel right for you- and that's what I did. If the cam works for you, and the compromises that panasonic has suggested are acceptable- more power to you :). Good luck and Happy shooting :thumbsup:
 
Ed Kishel said:
Yup, pretty much. I'm just that picky about sound I guess. The gh4 is indeed incredible, it's amazing how much camera Panasonic engineers have crammed into this tiny package. But it's the best bang for the buck right now. It's the "gotta have gear" right now. The 5D was there, the RED was there, the BMCC.... But there is always the future, and things move fast in the camera world. You have to be able to walk if it doesn't feel right for you- and that's what I did. If the cam works for you, and the compromises that panasonic has suggested are acceptable- more power to you :). Good luck and Happy shooting :thumbsup:
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Sure, to each his own :) But, I guess the things go well beyond our personal choice, taste, whatever self-centered actually, it is a matter of principle hence the discussion... Will this bug stop you, me, him, her? I am surprised to see your answer to the hassle, I beg your pardon : ) In the name of the open discussion topic here (not exactly a private matter) it doesn't seem a deal breaker at all the purchase of a piece of 100 bucks gear to begin with :-)
 
Worzel Gummidge said:
Audio on my video straight out of the camera seems fine to me.

https://vimeo.com/95249295
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Sounds fine to me as well, but you're not testing for the issue properly. My niece's Hello Kitty camera sounds pretty good to outside. Sorry, but this is another example of a posting of audio with nat sound during some other shoot. Birds chirping, cars driving by, kids talking- all of these things make it hard to hear if you are experiencing the issue. The real test is quiet audio environments- like during an interview. Folks who want to post their own audio tests, please read the entire thread on how to properly setup your GH4 audio settings. Then post please :)

Here is the quick and dirty:

1) hook up a mic with a 3.5mm jack, and turn the mic off
2) hook up headphones
3) turn your headphones vol to med (10)
4) turn your mic input level to default (0dB)
5) record a file in manual movie mode

If all you hear is white noise- you're good to go. If you hear white noise and a buzzing sound, well.... :happy:
 
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