The FIRST thing to know is one name - Sony.  I am not a Sony brand-whore by ANY stretch of the imagination.  It is much more basic than that.  Sony is the ONLY brand that offers TRUE 0Lux functionallity that actually works in their lower lines of equipment.  Several other companies claim to have "Low Light" features but we aren't interested in "low light".  We want ZERO light functions.  Apparently Samsung also offers some 0Lux functions but I have yet to find a model with this feature, let alone one at a price I am willing to pay for a "test".

Why Sony?
So for now I will say that ONLY Sony offers TRUE 0Lux function.  This is not to say that it is STELLAR in its OEM form - but it can be made stellar with an additional $40 worth of add-ons.  JVC and Panasonic's low-light functionallity is still useless for us no matter what you do to it.  This is due to how it works.  In both cases the apertures are opened up and the gain is increased.  Since light is still needed and those 2 steps may still not bring in enough by themselves, framerate is also decreased.  Normal NTSC standard is 30 frames per second.  These low-light modes cut down as low as 15 frames per second.  What you get is a round-about way to get twice the light to a single frame (with frame rate cut in half, each frame's exposure time is effectively doubled).  You get nice bright images - but they are grainy and choppy.  Sony's Super NightShot is useless as well for the SAME reason.  Luckily all Sony cameras come with 2 NightShot modes so Super is not needed or used. 

Sony NightShot
Sony's nightshot is pretty simple in application.  I won't go into the deep tech or specifics on how it works and the different modes offered over the years.  All you need to know is that digital imaging CCDs can see into  at least the "near-red" (NIR) spectrum, which is not visible to the human eye.  By itselfNIR is not TRUE infrared but it is close.  Most TV remotes operate on the wavelengths that are on the threshold between IR and NIR.  It doesn't take much effort to get a digital CCD to see fully into the true IR spectrum.  A bit of tuning and a filter is really all that is needed.  Add in an LED that emits light on an IR wavelength and you have a light source and associated imaging that works in complete darkness.  This is what Sony has done with their NightShot. One thing that confuses people is that they think that Sony's NightShot works by reading heat signatures.  This is not at all true.  IR is used for this but not the IR used in NightShot.  All Sony is doing is lighting the subject with an IR light that is not visible to us - but the cameras CCD can see it so the light becomes a source of illumination.

What to look for in a camera
There are several features that MUST be included on a camera for me to buy it.  THIS is where making a decision can get tricky as I will explain in a minute.  The key features I look for above and beyond all else are as follows (Listed in my order of importance):

Accessory/Hot Shoe
I need at least an accessory cold shoe but a hot shoe is a nice addition if available.  As I hinted at before, Sony NightShot still needs a little bit of help.  This is where the accessory shoe comes in.  Having one allows you to mount an IR light onto the camera instead of having to use an arm mounted to the bottom of the camera.

Microphone Input Jack
Camcorder mics suck.  Most people don't really rely on the audio they get from their video footage.  I am no different HOWEVER I do use it for verifications/cross checks of other audio evidence so it does serve a purpose.  I prefer to run an external zoom mic to increase the quality of the audio.  If you want to run one you need this jack.  Without it you are shit out of luck.

Headphone Jack
You won't need it often but you will occasionally in the field and when you do having it is an absolute lifesaver.

Now my list is simple.  However Sony, in their infinite wisdom, has been including those 3 features less and less with every new generation of camera (In fact - of the 3 current model of MiniDV cameras only the highest level DCR-HC96 has an accessory shoe and none of them have mic or headphone jacks).  If you are willing to roll with Digital8 then there are quite a few options you can choose from.  If you want to run MiniDV, HD or one of the various flavors of 1080i HiDef your options are very limited and for the most part quite expensive.

What cameras do I recommend?
I personally prefer the MiniDV format.  I think it offers the best of what is out there (I even prefer it over hard drives in 1080i HiDef models).  Media is cheap and plentiful.  Quality is broadcast level through 2 generations and the equipment is small.  For someone on a budget there are 3 models that stand out to me.  BOTH offer all of the above function, NightShot, MiniDV and can usually be picked up off of eBay for under $200 (I picked one up as cheap as $55). They are the :

• DCR-HC20 
• DCR-HC30
• DCR-HC40

Note that other models in the HC line all drop at least one of the above features.  These are the ONLY 3 Sony MiniDV non-HiDef cameras to include all 3 of the above features.  A hotshoe is much more common but that damn mic jack is a bitch to find nowadays.

If you have $500-$700 burning a hole in your pocket then look to one of the following:

• HCR-HC7 (MiniDV 1080i HDV)
• HCR-HC9 (MiniDV 1080i HDV)
• HCR-SR1 (Hard drive 1080i)

The options open up a good bit more if you drop the mic and headphone jacks but be aware that 80% of ALL Sony camcorders in the past few years lack ALL 3 features.  The accessory shoe is the single most important feature. Approximately 60% of Sonys DO have this feature.

For the record - the reason why Sony has all but dropped the mic jacks is because they have something called an "active interface shoe" which is basically an accessory hotshoe that has added connections.  If a camera supports this (More $$$s) then they feel that you can buy items like their $150 active interface zoom mic for it.  Marketing bullshit at it's finest.

About the best site out there for looking up camcorder specs is http://www.camcorderinfo.com. MAKE SURE you read up about the camera's features BEFORE you spend.

Good luck!