I am considering purchasing reefmaster to use with an autonomous boat that will capture sonar data on a humminbird side scan unit. The plan is to start the sonar recording and then send it out on pre-planned routes. This may mean that some sonar recordings end up being multi hours long. Will recordings of this length be an issue in reefmaster? Someone mentioned to me that there may be a max length of tracks that reefmaster can support?

There is no hard limit to the length of tracks that ReefMaster can support, although we do split them into separate tracks of 2.5m points each if very large tracks are imported. That is unlikely to be an issue in your case, though. Humminbird has (or had) a hard limit of around 20k track points per HT file, which is the logged trail/depth (this is dinstinct from the sonar logs). Again, probably not an issue since you will be using the sonar log, not the HT file, and 20k points @ 1 point per second is still over 5 hours of recording. As a general rule, we find it is better to record multiple, smaller logs if possible, just because it reduces the chances of losing data (corruption etc), and smaller sonar logs are a bit easier to manage within RM for things like sidescan mosaic. This is less of an issue when just using sonar logs to provide depth data for bathymetric maps.