I am not sure I follow; there seems to be something confusing in what I wrote before.
- A HumanObservation is the output of a human observation process - an observation made by a human.
It may be (and hopefully is) documented by a sketch, a photograph, video etc, or not at all. This documentation may be done with the help of a technical device, but the observation is still made by a human. - A MachineObservation is made by a technical device, without the need for a human to attend.
This device was set up, is maintained and is harvested by a (supposedly) human, but it operates on its own at the time the observation is recorded: a sensor-triggered photo or video trap, for example. A human may happen to stand nearby some of the time, but is not required to record the individual event. The observation will still be a MachineObservation.