External microphone - shotgun

[Kamelot]

Hello members,

I decided to buy external microphone for my 5D mk2.
Purpose is to avoid IS (24-105), focusing / zooming sounds and record more clear sound to concrete direction.

Would be great have stereo microphone and have modes: normal and tele or something similar.
Price range would be around 40 - 70 $. I don't need very expensive microphones like Rode or Sennheiser which costs 150 - 200 $ or more.
I made a little research of external shotgun type microphones and found these:

Audio-Technica Pro-24CM
http://www.bhphotovideo.com/c/produc...CM_Stereo.html

Audio-Technica ATR-6550
http://www.bhphotovideo.com/c/produc...icrophone.html

i am thinking about Audio-Technica Pro-24CM. It is smaller, has smaller battery and more clear sound (according to youtube). But i think, that because of lack tele mode it can capture IS and focusing sounds. So.. Audio-Technica ATR-6550 looks like panacea, but it is longer, has bigger battery (more weigth) and could be difficult to use viewfinder, if i want to take several photos and do not detach microphone.

Maybe here is owners of these microphones? would be great to hear advantages or disadvantages especially using on DSLR.
Maybe who could suggest any other microphones or share your experience?

[btaylor]

I'm sorry I don't know much about shogun microphones. I do however swear by audio technica gear in general. I use their in-ear monitors when I'm playing on stage and they are fantastic. I've got quite a few of their audio products and they are all amazing. So I would be confident that you're making a good choice with either of those.

I know that doesn't answer your question, just my 2c.

Ben

[Sean Setters]

You might want to look into an external recording device all together--something like the Tascam DR-07. That allows you to position the mic as closely as possible to your subject without the fear of camera noises being recorded. I bought my Tascam used off of ebay (for close to your budget), and it's been very handy for the rare times I shoot video. The only caveat is that the audio must be synchronized in post.

[jrw]

The quality of microphones ranges all over the place, and price is not always an indicator. Before buying be sure to check the specs for the frequency range of what the mic can reproduce if the sound quality matters to you. You should be able to find a graph in the technical specs. Plus or minus 3dBa is the normal signal strength range that is used to determine the frequency range covered. Many mics only effectively cover part of the normal range of the human voice, similar to using a land line phone. Also is worthwhile to look at the pattern of the mic, shotgun cardiod etc, and make sure that the coverage is going to be broad enough for your application. It doesn't sound pleasant when the subject you are recording is moving in and out of the effective coverage area, unless you are going for the fading in and out style.

[Kamelot]

btaylor: thanks

Sean Setters: thanks for advise, but external audio recording device would be too complicated for me due to post processing necessity. I just want to take home video of running childs and family members. I should have to put that device something near speaking person, go back to the camera and take video and if they want to move to another room or place, i have to replace external audio recording device too. I want to take video neutral, by do not disturbing speaking people

jrw: i made more research about mics, and found out, that there is important characteristics like these:

• sensitivity: -50, -40, -30, ... dB (bigger is better) and there is also measure in miliVolts like (3 mV, 7mV) where bigger ir better.
• impedance: 100, 300, 600, 1000, ... ohms (smaller is better). There is 3 ranges: till 600 ohms, 600 - 4000 ohms, and bigger. Where first range is the best.
• polar pattern: Omnidirectional, Cardioid, Supercardioid, Shotgun, ... by wikipedia http://en.wikipedia.org/wiki/Microph...polar_patterns
• frequency: 100 - 17000 Hz (i think it is sufficient)
• and many more characteristics..

So now i think, that would be great to have microphone, that could work in 2 mode: normal (Cardioid or Supercardioid) and tele (shotgun).


Audio-Technica ATR-6550 microphone has two modes: normal (Cardioid), tele (Supercardioid). But it's sensitivity is low: -56 and -45 dB. Impedance is also big: 1000 and 2200 ohms. I watched many reviews in youtube of this mic, and in tele mode there is high frequency loss a little. Also this mic is only mono, you can create only fake stereo.

Audio-Technica Pro-24CM microphone has only 1 mode - Cardioid but true stereo. Has greater sensitivity -50, lower impedance 600 ohms. Seems better, but..

Question is: will this Audio-Technica Pro-24CM mic with polar pattern Cardioid should pickup any sound of focusing, zooming, IS or changing settings of the camera?
From the one review in youtube i also heard, that you have to by shock mount to these microphones, because even Audio-Technica ATR-6550 in tele mode is very sensitive and records sound of the camera or buttons pressing.

Is it even possible to avoid camera sounds (focusing, zooming, IS) with directional microphone mounted on the hot shoe mount top of the camera? Or i have to find another solution to place microphone?
Any experience would be appreciated

[Busted Knuckles]

I went with the Alzo shock mount Tascam DR-7 that Sean mentions. I use a simple headphone splitter jack to give me two outputs - one for me, one for the camera. I turn up the gain on the recorder and down on the camera. Monitor the VU w/ Magic Lantern on the LCD screen.

If you are doing videos and of the Kids, etc I would still get Magic Lantern so you can monitor VU on the screen to make sure the audio is corrcetly set.

My two pennies

[jrw]

For creating stereo sound it is required to use at least two microphones. It is the spacing between them that allows for the recreation of the sound space when the recording is played back in stereo. A sound source will be recorded at different levels by both mics. It is the difference in these levels at playback that allows us to determine where the sound is directionally coming from. In an ideal world, mic placement would match speaker placement of the playback system to accurately reproduce the original sound stage.

To avoid camera sounds it will be necessary to place your mics off camera. A simple rule of thumb is that if you can hear a noise you don't want to include during a recording when your ears are in the same vicinity as the mics, the mics will have heard it too. Even a highly directional mic will pick up sounds from other directions, they will just be more attenuated than an omni-directional mic.

When it comes to the mic specs, do not fall into the trap of thinking that the impedance measurenment in ohms is the same as a resistor. The three individual measurements that comprise impedance are inductance (Henrys), capacitance (Farads). Coils are used in mics so inductance will matter. Unfortunately, inductance is also frequency dependant. Any major dips or spikes in the impedance/frequency graph means the mic is not properly compensated and will be noticed in the recordings.

[jrw]

For anyone who ventures into the land of mics and audio equipment I am providing a link to one of the best websites I've found over the years.

http://sound.westhost.com/

The articles are informative and there is some mic info buried in there in addition to a couple of articles expressly about mics, the power supply, and amplifiying the signal. For those who don't have an electronics background, I'd suggest that if you decide to move into building any of the projects that you work with someone who does. You're not likely to kill yourself, but mistakes can be costly when equipment starts to issue forth billowing clouds of distress which could have been prevented with proper bench testing methods.