Further safety rules

1.

Before viewing a source, select the DIRECT viewing mode on the Grinnell buttons.

2.

When pointing at a field, even if you know it only contains 18th magnitude objects, turn up the gain SLOWLY whilst observing the effects on the direct (raw video) TV camera monitor.

3.

As the object or field of interest appears on the direct screen, adjust the gain control to give a sensible picture on the Grinnell monitor.

4.

If the gain control reaches maximum without ill-effects on the direct screen and further gain is required, then select AVERAGE mode on the Grinnell and adjust the number of frames of integration ONE step at a time waiting between steps to see the resultant image. When the Grinnell is in the AVERAGE mode, the direct monitor will flash the integrated signal with a period equal to the integration time.

Finally, at the risk of being boring, be EXTREMELY CAREFUL ON BRIGHT STARS - if an object looks too bright in the monitor then it IS too bright so turn down the gain p.d.q.