vMix is a great program for broadcasting in SD or HD. It is very efficient with regard to CPU load which allows for use of a modest PC and is capable of multi bit rate broadcasting as well as using single or multiple camera setups. vMix has many other great features including transition effects, recording, virtual sets with chroma key, desktop video sources, built-in title templates, video delay and instant replay, built-in audio mixer, live video effects, overlay channels, and much more which help produce a very professional broadcast. They offer a free version with up to two SD video inputs as well as premium versions for HD and more video input options (starting at about $60 for the HD version, a one-time purchase price). Plus, they have a program where some qualifying churches may be able to get a free HD version.
The first step to use vMix is to go to the vMix download page to download and install vMix. This can be found in the Sunday Streams Manager by clicking PC Encoders > vMix > Download. Once installed, you can get started quickly with the Quick Setup settings. (vMix does have the option to set up your stream by entering your Sunday Streams Manager username and password. This works well if you want to send out a single stream, however if you want to send out a multi bit rate stream you will need to use the custom RTMP option with the Multi Bit Rate settings from the Manager. Additional setup details are covered in the short help video below. After you set up vMix please enter the resolution(s) and bit rate(s) you have set on your encoder in the Sunday Streams Manager on the Broadcast Settings More > Bit Rates & Resolutions page.
vMix Setup Help Video