youtor.org
Alt Az GoTo Mounts Vs Equatorial Mounts And Field Rotation
>> YOUR LINK HERE: ___ http://youtube.com/watch?v=fJ3r7RQs03k
Explains field rotation simply with photos, and covers how Equatorial mounted telescopes cope with field rotation while Altitude Azimuth mounted telescopes cannot. Also covers the fact that you are not limited to the often quoted 20 seconds in Alt Az astrophotography, because in some parts of the sky 60 seconds is possible, while in other parts of the sky only 5 seconds is possible before you get field rotation effects. It also offers ways to figure out better times to shoot those objects (IE when the exposure times are longer). Link to my flickr album which shows the max exposure times for objects in different parts of the sky for any latitudes is https://flic.kr/s/aHskL4YGR5
#############################
