I'll start making the 50 hard boiled eggs we'll soon be needing.
Seriously, I note the poster is from Malaysia so English is likely not his first language. If that's that case, he speaks English better than I speak Malaysian.
I'm going to guess he means Large diaphragm versus Small diaphragm mics.
The first thing to say is that small diaphragm condensers are NOT all shotgun mics--indeed, most are not. They have similar polar patterns to their large diaphragm brothers, cardioid being the most common for both.
Which are best for acoustic guitar? It's purely down to personal taste.
Small diaphragm mics tend to have a slightly more detailed, crisp sound while large diaphragm mics can be a bit "warmer" in tone. However, there are large amounts of overlap in the centre. My personal taste is for small diaphragm condensers (generally AKG 451EB or 391 or sometimes the sE1A) and a stereo recording because I think acoustic benefits from good detail. On the other hand, I've also used LDC mics in single and double mic configurations. It really is down to a mix of the sound you want and also the sound that comes from the guitar in the first place.
