Re: Request for Assistance

Ron Lee (
Thu, 03 Jun 1999 10:29:08 -0600

My 7x50 binocs have a printed (on the binocs) field of view of 6.8 degrees.
I will guess that yours are in the 5-5 degree range. You can print out a
star chart with easily found stars and declination or azimuth/elevation
grid lines.  Put one star at the bottom or top and see what star(s) is at 
the other end. Compare to the star chart and you have your field of view.

You can do the same thing with your telescope or use the star drift method.
Point to a star near the celestial equator and time the period it takes to
drift across the MIDDLE of the eyepiece. One degree would be four minutes.
0.5 degree in two minutes; 0.25 degree in one minute, etc.

Ron Lee
>Here is my problem.  I have a very difficult time "getting my bearings" when
>comparing a star chart from Celestron's The Sky or SatSpy v3.0 to the night
>sky.  I have a lot of city light in my night sky.  My question is, how can I
>tell what the field of view is (in degrees) in my 10x50 binoculars or my
>4.5" Newtonian Reflector?  Perhaps this would help me "get the picture" when
>I look up.  (I really wish they would draw the lines connecting the stars...