Let's drop the use of the poor quality internal reference microphones, or relying on shotgun microphones placed upon the camera. Up your audio game with affordable microphones and sound recorders.
When thinking about what microphones and sound reading solution you want as a wedding videographer you have to consider many things.
1) When do you need to record better sound 2) How quick are they to set up 3) Will the people you need to hear wear a microphone or do you need a different solution 4) Do you need the sound to be live or can you use a recording device 5) What are the mounting options for the microphone 6) Internal or external battery and storage ( how long do you need?) 7) Budget versus sound quality 8) Options versus ease of use and automation
There are probably even more questions to ask, but the main thing is you have a range of solutions for different situations that you might find. These need to be as easy as possible to setup and also need to capture great sound.
1) When you are a videographer at a wedding you have loads to consider and sometimes you just need a quick sound recording solution that will just work. Sound recorders can be set to self level and can be as simple as place, record and sync to your footage in post production. The downside is obviously you can't monitor the sound and are no good if you're live streaming the wedding. There are now hybrid solutions such as the DJI mics and the Rode wireless Go II which can send the sound to a camera and also record at the same time. We talk more about these later.
2) A couple of high quality directional microphones are a perfect solution for many sound recording needs at a wedding. Placing it onto of your camera will automatically increase the quality of your sound over an internal camera microphone. If you buy a shotgun microphone with a built in battery or an option to insert a battery, you can also easy send the signal wirelessly to your camera or computer, enabling you to place it nearer the action whilst you are out of the way filming.
We use the Rode NTG4+, its sound recording pattern is super cardioid, which means it will record in the direction its pointing with minimal sound picked up from the sides or behind.
3) Lets talk wireless before we talk lavalier. We use the Sennheiser xsw series to send sound over a short distance and they work great. The main reason I like them is it almost does away with the need for cabling and can neatly plug into cameras microphones and even sound desks to get a signal from the venue or DJ. They don't record internally unlike the Rode Wireless Go II which you can also use to send a signal to your camera, however you will need wires to connect to your camera and to any sound desk etc.
So wireless is useful for getting your sound recording closer to the action, then wireless lavs are perfect for the same reason. For vows, speeches and readings clip these onto the key people and plug the receiver into your camera and you can monitor the sound as you film. You will want to pick up some high quality lavaliers such as the affordable Sennheiser ME2-II Lapel Microphone. These can plug into the Wireless Go II, Seinheiser xsw and the Tascam DR10L sound recorders.
4) Outside ceremonies can be an extra challenge when trying to capture good audio and you will need to consider ways to reduce wind and other outside noise. One popular and easy way to to add a dead cat or fluffy to your microphone of choice. This will transform your sound from unusable to usable quite quickly, so just make sure you have an option for every microphone you intend to use and attach it.
If you don't have a fluffy, the next best option is to mount microphones under clothing or to hide a sound decoder in the flowers on the ceremony table where it will be protected from the wind.
5) Good sound is key fro a great film, if you don't own many microphones there are some "make-do" solutions you might consider.
1) Use your phone as a sound recording device by placing it near the venues or dos speakers when they are using microphones. You can also plug in an inexpensive lapel microphone to your phone directly and use a voice memo app to record the sound directly on your phone. This is often as good as using any other sound recording device, but just make sure you phone is in airplane mode!
2). Use inexpensive cables to take a sound feed from the venue or DJ straight into your camera for the ceremony or speeches. Check your cameras connection and then buy the appropriate cables to attach ( TRS,XLR are the most popular to get a sound output from a desk or wireless receiver).
3). Use a on camera shotgun microphone of the best quality you can afford and make sure you are closer to the the sound you need to capture. If all else fails just get closer to the action and record the sound with your camera. Sometimes you can place yourself close or underneath a speaker for the speeches for example.