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Old May 11th, 2009, 03:46 AM   #16
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Quote:
Originally Posted by Matthias Krause View Post
Wow, thatīs a big difference: Your cam dialed all the way up to 10 checks out at around -50db... Seems like there is something wrong with my cam... Should not make a difference, but are you using .mov files or .mp4?
Thanks a bunch!
I will put up the camera file to make sure there is no misunderstanding. .mov or .mp4?
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Old May 11th, 2009, 01:47 PM   #17
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So can someone please sum up the final solution, as I am a bit lost in the maze of these posts?
- Is there a hiss in audio?
-How can you eliminate it?
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Old May 11th, 2009, 02:23 PM   #18
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Every pre-amp produces some hiss. The question is how much. My camera is very hissy, apparently much more so than the one Elvis has. I am going to send mine back for a replacement that hopefully will perform better. Otherwise I will have to go for a different model because it is basically unusable. But I am hopeful since the hiss levels Elvis gets with his cam sound pretty ok and manageable.
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Old May 11th, 2009, 02:29 PM   #19
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I just tried the mic in out auto/manual thing

and basically if the manual control is set to:

line ZERO hiss
Mic +48 auto gain or manual control above zero - minor hiss
mic+48 manual control zero - no hiss

so the mic preamps do create a bit of hiss on mine - but not distracting amounts
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Old May 11th, 2009, 03:08 PM   #20
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I spoke to a friend of my, who for years worked in a recording studio. He was wondering about the microphone on the camera.
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Old May 11th, 2009, 03:41 PM   #21
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Originally Posted by Robert Rogoz View Post
I spoke to a friend of my, who for years worked in a recording studio. He was wondering about the microphone on the camera.
And he is right.

Do the same test, but short the mic inputs to ground (make sure phantom power is off first!), turn the mic gain all the way up, turn any other level controls that affect the gain in the camera before the sound is recorded all the way up.

The noise levels in the two recorded files should match between two cameras of the same make and model within at least 20% or so. If not, there is a problem with one of them..

-Mike
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Old May 11th, 2009, 03:42 PM   #22
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The shotgun mic that comes with the camera is super cheap and probably should be replaced. If you want a cheap $3500 camera then it should be fine. If you want a pro quality small camera then you should get a better mic.

There is some hiss but it isn't horrible. You can use some eq to bring down the highs where most of the noise is or get a more sensitive mic so you need less camera gain. You could also get a portable recorder and plug your mics into that.
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Old May 11th, 2009, 03:55 PM   #23
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Originally Posted by Elvis Ripley View Post
The shotgun mic that comes with the camera is super cheap and probably should be replaced. If you want a cheap $3500 camera then it should be fine. If you want a pro quality small camera then you should get a better mic.
One would hope that if you spend $3500 for a camera it would have a microphone for $3500 camera, particularly with uncompressed sound. And that was my point a few months ago, that charging customers for worthless microphone is a bad business.

Quote:
Originally Posted by Elvis Ripley View Post
There is some hiss but it isn't horrible. You can use some eq to bring down the highs where most of the noise is or get a more sensitive mic so you need less camera gain. You could also get a portable recorder and plug your mics into that.
That would pretty much defeat the purpose of the small size of the camera.
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Old May 14th, 2009, 10:28 PM   #24
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Reference Level

I replied to another post and realized that if you set the audio reference level to -12 dB instead of -20 db then you get 6 dB of gain without adding hiss. If you have something really quiet this is where you should turn it up first then dial up your analog gain on the handle.
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Old May 27th, 2009, 08:05 AM   #25
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So the consensus on the typical HM100 audio is ...

... just plain and very unfortunately Hissy?

Only as much hiss as anything else below $5,000?

Enough hiss to make the uncompressed LPCM a bit too polluted for true professional audio use?

*** The HM100, aside perhaps from a few lemons, has perfectly acceptable audio for professional field use WITHOUT add-on devices aside from mics??

Please describe a bit so that those of us poor souls in the dark that are considering buying one can get a sense of the problem -- or is it a non-problem?

This might be my first camcorder purchase EVER, and I'd like to make it a good one :)

THANKS!

~ Shaun
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Old May 27th, 2009, 12:55 PM   #26
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I think this isn't a problem. Setting the audio level manually keeps the auto gain from turning the level up too much. This is normal for a video camera. I have used it quite a bit and don't have any issue with it.


When you get the camera set the audio reference level to -12 for normal stuff and -20 for louder stuff when you need more headroom to make sure you don't clip.

Set your audio level manually which is what you should do. If you have time to manually set your shutter/aperture and gain then you have time to set your audio level.

You should also get a better mic if audio is important to you. This is also normal for a video camera. For $200 to $300 there are plenty of mics that will really give you a big improvement.
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Old May 27th, 2009, 01:57 PM   #27
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So for shooting with AGC ...

So if I am in a run'n'gun situation where I'm shooting everything full auto for a while, and it's in a quiet but rushed situation, the AGC on the HM100 won't be any worse than AGC and full auto on say, a Canon XH A1 or a current Sony prosumer HD cam? ... or what would be a well-behaved prosumer camera that behaves well in full-auto run 'n' gun style when you really need it to, this HM100 or ?

Thanks -- I'm sure looking forward to having two real built-in XLRs, phanton power, and adequate manual level controls and meters. The last time I shot video for more than a bit, it was on 1990ish AG-1xx series cheap industrial-consumer S-VHS Panasonics ... We just had our professor's ME60 plugged into the mono mini Mic jack with a cord that had an attenuator or ? on it.
I plan to get a Rode Rode NTG-3 Shotgun or a Sennheiser ME66/K6 and other modules, probably the latter.
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Old May 27th, 2009, 02:17 PM   #28
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I think it will be about the same. You could have channel one set on auto and channel 2 set to manual 2 just in case the auto goes too loud or the source gets too loud for the auto to handle. It is just a way to have a backup of the audio in case your level (auto or manual) is incorrect.
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Old May 27th, 2009, 09:55 PM   #29
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Just to be clear: I never use AGC for my audio and that was not the problem I had. I sent the camera back and got a new one by now. The hiss on that one seems slightly less but still not great. I wish I had my AKG mic on hand to test the cam under real world conditions and not only the crappy mic that came with it. When I use my Sennheiser wireless system I donīt have any problems, because I can turn the gain in the camera down to 3. So for me the jury is still out on the pre-amps but they are at least usable and since I like everything else the camera has to offer A LOT, I will keep it.
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Old May 28th, 2009, 05:33 AM   #30
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you can probably use your radio mic on Line level input too, not much chance of noise there and the gain level is set at the transmitter end so other than unexpected overshooting the level there you are safe once you set the input level at the camera end.

I haven't been able to check out the HM100, but I am considering getting one in the very near future.

I use the GY HD100 and often use auto + manual for safety with Rode NTG1 or NTG3 + both these mics put out plenty of level. I have also used the AT 835b with success (less sensitive and less detailed but still a decent budget long shotgun - although at 13" length not for camera mounting).

I have never heard hiss on that cam except back when I was using the "poundland mic" that came with the camera, probably the same one.

First thing I did was replace it with the NTG-1, and last year replaced that with the NTG-3 (which is miles ahead of the NTG1 in capturing detail).

I think don't auto works like agc on these cameras - more like a moderate level of gain with some limiting applied. They will compress loud sounds but can still clip. It was even that way back on the old Sony VX1000. Auto was safe with no pumping of the level in quiet parts.

Generally unless you work in a controlled environment like a studio I would expect ambient sound to be considerably higher than any noise floor on the inputs themselves.

Last edited by Les Howarth; May 28th, 2009 at 01:01 PM. Reason: typos
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