I'll no doubt get flamed by some of the audio folks, but that's okay.

I've used the little Sony ECM-MS908C stereo mics ($100) on my surround-sound setup for the past year, and last fall I treated myself to the Audio-Technica AT822 stereo mic ($300). I've had a chance to compare the AT mic to the Rode NT4 stereo mic ($500) along with a pro friend who has a much more refined sense of music than I do (he's a keyboard pro for James Horner, the composer of numerous cinema soundtracks, including Titanic).

My initial assessment is that the AT822 and the NT4 are essentially flat from a frequency response perspective, while the MS908C varies perhaps +/- 5db here and there (I conclude this after running pink noise through them with an inexpensive Spectrum Analyzer). I conclude that one can easily equalize out the hilly terrain of the MS908C.

Background noise level is a different matter. The noise level of the inexpensive Sony mic is much higher than the other two. For my purposes (on-the-move documentaries) it makes little difference, and the noise is not much of a factor in my live recordings, given the ambient noise. For a pro in a sound-controlled studio I presume it would make a huge difference.

My feeling about mics in the field is that the more you have invested, the more it's going to hurt when one gets stolen or broken (and they will). Save your money and future heartache by buying good fieldworthy equipment that can take a knock without quitting on you, and that you can replace when it's time without mortgaging your home. Without getting into a debate over minute details, there are good shotguns and condensors in the $200-$600 range. You don't need to spend any more. The elitists who miss the "warmth" of their $10K tube mic should stay in the studio!

Insuring your equipment and bonding your grips and roadies is an absolute necessity if you do a lot of this.

Farss,
There is a point of diminishing returns, depending on what you are doing. Mics have self-noise (noise generated by the mic itself) and the more you pay, the lower it goes. Better mics also provide a more accurate sound when used correctly.
Can you fix most differences in post overall? With todays plugins, yes.
Can you make a 50.00 mic sound like a 5K mic? Likely not.
Does a $5.00 mic close to the sound source sound better than a $5K mic 10-15' away? Absolutely. But a reasonably priced mic close to the source will sound great. Depending on the source and the mic, I rarely do any EQ to certain things I do, simply because the particular mic I choose does the best job overall.
I DON'T believe in the school of "more expensive is always better." 90% of my work is accomplished with the AT 4000 series, especially the 4053. I also use the 897 and 815ST a lot. I use the Rode NT4, and use the BK 4011 and 4001 mics quite a bit, and use the AT 3060 for most male V/O's. The Shure SM91 is good for choir work and a few other specialty things, and I use ECM series and AT 899/831b's religiously. None of these cost more than 1200.00 each. I don't know that I'd agree with Musicvid's assertion that there are good shotguns in the $200.00 range, but you don't need to spend 5K either. The AT 897 has made a tremendous stir in the field recording world, and the Senn ME 66 has too. I don't like the ME 66 because it's very hot and somewhat shrill, but to each his own. Both AT and Senn are sub $500.00.
I do have an old Shure 55 that I occasionally use on a female V/0, and have a large selection of old mics from 1950 and earlier that are mostly for hobby/collection, but they occasionally get dragged out.
In other words, I don't use the DPS, Schoeps, nor high end Sennheisers. Not because I can't afford them, but because I don't feel I need them. I also don't use Azden mic's either, because to get a great sound with them, I find I have to fiddle around a lot. As Daryl commented, one of the big differences is the amount of time saved. But there are some mics that are so far out, such as the 5dB diff that riredale speaks of, where you're doing so much to the sound, it's clearly obvious.
After CES, I'll post an example of a really badly recorded V/O and comment on the hours it took to clean it up, whereas if a good mic/soundcard, and recording theory had been employed, it would have been a 5 minute touch-up.
Jeffrey Fisher is teaching a class here at CES on this very subject. He also covers it in his Forge DVD.
Finally, in the Now Hear This DVD, there is no eq on any mic in that vid, so that you can hear the differences between a huge variety of mics in a wide variety of price ranges. What we did was to put up a titled graphic of "You're hearing the XXX mic from XXX" so that viewers always know what they're hearing.

In terms of large diaphragm condensor mics, I have used everything from neumans to the $80 MXL's on ebay. Ray Charles (if he were still alive) could sing into the MXL and sound great. A turd could sing into the neuman and still sound like a turd.

Is the mic going to make or break your project? The answer is.....NO!

The MXL's sound surprisingly good. They have their problems. They are not going to sound as good as a neuman, but If I were given the choice of having a VO done by James Earl Jones through a MXL, or just an average VO guy through a neuman, I will go with the James Earl Jones through the MXL 110% of the time.

That being said, buy the best mic you can afford COMFORTABLY!!! Do not blow your whole budget on it. It will save processing time later, but do not be affraid to use a mic like an MXL or the cheaper CAD mics if that is all you can afford.

Al

If you want to hear a bad mic, check out John Fogerty's Blue Moon Swamp cd and listen to a 53 year old voice made to sound like 13 years old. At least I think it was the mic.

JJK

First, realize that video cameras stink for recording audio.

If you spend $100K on a Sony HDCAM (without a lens), you get decent (not fantastic) sound on the tape, but the sound from the headphone jack is awful.

Anything less than that in video equipment stinks for audio recording, although at various levels of stench.

To justify really expensive microphones etc., you need to use parallel sound, ie. recording to DAT or nowadays increasingly to harddisk or flash memory.

I happen to use a $1,500 shotgun (Sanken CS-3e) and it has an absolutely wonderful sound quality, but that is not the #1 reason I bought it.

Sennheiser's MKH-416 sounds nearly as good and can often be bought for under $1,000.

No, the difference is that the Sanken mic doesn't color its sound when picking up dialog off-axis. It sounds about the same over a 40 degree range, which simplifies shooting a LOT.

Additionally, the Sanken mic rejects external side noise that would make recording with the Sennheiser mic absolutely impossible.

There are many other types of "vocal mics". If you need a good cardioid or hypercardioid, Schoeps has some exceptional mikes for about $1500 that are used a lot in TV series and feature film productions.

On the other hand, you can get more than 90% of what those Schoeps mikes offer in the Audio-Technica AT4051 for $500 (and it too has interchangeable elements for card/hypercard characteristics).

Before you blow a hole in your wallet with a massive microphone purchase, get something good to record on. If money is no object, consider the Sound Devices 722 or 744T for a few thousand dollars, they sound quite wonderful and are very robust.

(I am intentionally not even mentioning the $10,000 Zaxcom Devas and some other $15,000 audio recorders :O), they are really for major budget feature films).

There is only one way to get really high quality sound recorded together with the video signal. SDI (Serial Digital Interface) with an embedder box inserting 20-bit audio using your own electronics. This way you are not letting a camera manufacturer touch your precious audio. It entails additional expense and more boxes, but if you gotta have the good sound and no synching in post...

Generally speaking, for most picky people (who don't mind the extra work) it makes sense to record audio separately from the camera, and to use the camera audio only for backup.

Well, let me throw a wrench into the machine. I've noticed whenever you guys start talking mics, PZM is never mentioned. What are you more experienced guy's opinions of the Crown PZM microphones for echoy/reverby rooms?

How bout the "MR Micrcrophone" pro series?
(always the smart ass,aren't I? )

Really though, how would you guy's rate the AKG C1000s Condensor?
It's a Mic I've had for a while, useful for audio for video?

Oh dear,
this is starting to sound one of THOSE threads from an audio forum!
I think we can pretty safely assume for OUR practical puposes that any large diaphragm condensor with a decent noise floor is going to be as good as we need.
See what I was really trying to get at is this. Take speakers, you can get a cheap ones and medium priced one and the specs look pretty much the same. This is because of the way the specs are derived. Run them thru more advanced analysis and you start to find really nasty bumps in the response, those bumps will also usually mean nasty phase errors as well. Now these are issues that border on the impossible to fix with Eq or anything. So in general you do get a pretty linear return for your dollar with monitor speakers. They may look the same, the specs may look the same but the sound will be noticeably different and the errors in poorly designed speakers cannot be fixed.
But from what I'm hearing regarding microphones the same thing doesn't apply here. In general for jobs that you do maybe once per month, not many times per day, you're not getting any real return for your dollar between the median priced gear and the most expensive. Or to look at it another way, those dollars could be better spent elsewhere, perhaps better monitor speakers.

Bob.

"experienced guy's opinions of the Crown PZM microphones for echoy/reverby rooms?"

There are many manufacturers of PZM mikes today, Crown just invented them originally.

PZMs can be helpful sometimes, but it depends on what you are trying to capture. If you are snagging dialog of two people in a room with bad acoustics, you can get better results with a good cardioid or hypercardiod mike held within 2 feet or so. Big subject!

"how would you guy's rate the AKG C1000s Condensor?"

I had two and sold them both, couldn't stand the sound of them for either voice or instruments. I tried three different micpres, couldn't find any combination that helped.

Many others are happy with them, although I can't understand how.

Thanks, I was never real happy with the sound either , but wasnt sure if it was my inexpirience with the eq on the board, cuz when set at flat I couldn't stand the sound.I was always tweaking and never happy.
I'm gonna look into some others as well.