I use a high-power microscope to examine specimens of small insects. I can attach my Nikon D90 to the microscope, and using the hdmi output from the camera in LiveView mode I should be able to view the result on my laptop screen - I have downloaded OBS Studio and use a USB3 capture lead to connect to the hdmi (normally output) port on the laptop. What settings in OBS should I then use - it seems a pretty complex suite.