NavList:

Robert VanderPollII you whote: GKolbe brought up the narrow field of view. In addition to pre-calcing altitude and azimuth, there is a guide for periscope sextants that has drawings for each of the 57 navigational stars that depicts what they should each look like, that is what are the minor stars around them. That way if you see a major stars but the surrounding image is incorrect you know that you've MIS-identified what you are looking at. 

I don't recall where I learned of this but I saw an example for one of the stars and it immediately made sense.  It might have been several years back when we were discussing the British airliner in Africa that went off course and crashed in the desert when it ran out of fuel. 

Oh, for the days when one needed to worry about distinguishing between navigational and other stars.  These days I worry about being able to see even the less bright navigational stars though most of my sextants.  The 15 degree eyepiece views are still there in the back of the Air Almanac (which you can download foc).  I think the present diagrams tell you almost too much.  You’d need perfect vision to see all they suggest you should see, even from FL430.  You do need them when there’s nothing to be seen outside apart from what you can see through the sextant eyepiece, but if your pre-calculations should be wrong (unlikely in a multi crew aeroplane), it’s still very easy to latch onto the brightest star in the field of view.   DaveP