Are battery/plug-in powered mics ever acceptable outside of field recording situations (e.g. home recording)? Are studio-oriented microphones ever acceptable in the field? I'm sure there is some overlap among microphones. Any pointers on what specs I should be looking at when determining if a microphone could be used for both? For home recording, I'm leaning towards a small-diaphragm (because most can also be used for live sound reinforcement. Would any of these be acceptable for field recording?
For live onstage mics most people use dynamic mics for vocals and often everything else. Condenser mics don't like to be handled. They are more sensitive and would pickup handling noise. Most dynamic mics don't need phantom power and can handle rough handling. That's not a condenser mic that Roger Daltry was swinging by the cable at Woodstock! You'll see some bands occasionally using condenser mics for mic'ing amps or for drums overheads. You can sing into a condenser, just not hand hold it. Condensers don't like people blowing into them either. They also don't like moisture. Of course, like everything in the world there are exceptions, this is in general.
So, yes, you can use your condenser mics in the studio. Most of the mics we use in the field ARE studio mics. I bet like most people, you will become very protective of your condenser mics. You want a matched pair if possible.
I can't speak intelligently about the merits of large diaphragm mics over small diaphragm. From what I've read I gather that large diaphragm mics tend to be more sensitive. Its NOT a matter of big diaphragms handling lows better or small diaphragms handling highs better.
Here's a suggestion, go to the Live Music Archive (archive.org) and read the text files for a bunch of the shows. Most will list the gear used. You will see patterns. Maybe copy and past those lists to a text document to review later. You'll find the same makes and models of gear over an over again, often in the same combinations. Those are the combinations that people have found that work well. Look up the gear. Often the listing is cryptic looking but usually if you plug in the term in Google, you'll find the gear. Some you will eliminate because its more expensive than your budget will allow. What is your budget?
Another thing you can do is Google a model number and see if it shows up associated with a live recording. If it doesn't, why not? Might be new, but probably because its not good for that use. if it comes back associated with a lot of live recordings, its good field gear. Maybe not good for you though.
Once you have your list of affordable field recording gear, then you have to compare features. A spread sheet can help with that. Features that matter to you along one axis, models down the other. Put check marks where the features match the model. The evaluate and cull out the stuff that doesn't meet your criteria. Finally search the web for reviews of your short list.
Don't forget to include the cost of the other stuff you'll need like stands, cables, shock mounts, adapters, bags to carry all that stuff around, etc. Those costs mound up fast. And some of what we use you wont find in a Musician's Friend catalog. For stands many of us use stands intended for photographer's lights. Why? HEIGHT! We are trying to get into clean air well above the crowd's heads and away from their yapping mouths. If you don't get your mics up, you will soon hate everyone around you at concerts. They are also usually lighter than standard onstage mic stands. Get a B&H Photo catalog to shop stands but search the web before buying from them. They are good people with fair prices but often you can beat their price. Many of us use custom made mic cables. Commercial cables will work, just don't buy cheap cables, they will bite you in the end. If you get cables from Guitar Center, buy the good ones! Not the stuff on bargain basement sales. Use shock mounts and good windscreens on your mics when possible. Reason? Why have your recording messed up because some yahoo bumps into your stand or there is an air conditioner draft blowing on your mics. It happens.
Oh, mic specs. SPL rating if you are going to be recording loud shows. And "loud" doesn't mean heavy metal. I've seen bluegrass bands that were blasting. What frequency range can it handle and how well does it do that across the spectrum? Flat across the board is good but some folks like a bump at one end or the other. What level phantom power does it need. I heard of one model mic that required MORE than 48V. Obviously that would be a problem.
More:
http://emusician.com/tutorials/emusic_mic_specs_demystified/http://broadcastengineering.com/mag/broadcasting_reading_microphone_specifications/Just Google "microphone specs"