Solar Tracking

[Ron Hillstromb]

Hello All

  As I prepare for the Solar Eclipse I am finding some information in some cases and having my memory jogged in other cases

  Some or most probably already know this information.  For those who don't the Sun tracks slower that sidereal by .35%.

  For those with motorized GoTo mounts  here are some thoughts to meet this challenge.   My Meade mount has Sidereal and Lunar but not the Sun.  It does have a custom setting.  Thanks to a patch by Dick "AutoStarETX" Seymour the rate has been expanded to 100X setting capability.  I am able to set the custom setting to -35 which is .35% slower.

  If you have a Custom setting for tracking on your mount but it is limited to tenths of a percent then Dick suggests you use 3.

  An alternative to this, if you don't have a custom setting and your photo plan allows it, is to use Lunar tracking and center on the moon, as close as you can, when it begins the eclipse.  By tracking the moon at the Lunar rate you should be able to get the partial eclipse phases as well as totality close to being centered depending on your focal length.

  Getting the Sun into the field of view for those with out having an entry for the Sun can be accomplished by going to Venus to get close then adjust the mount until the Solar Finder or using the shadow method all lines up and the Sun is in the field of view.  This is most practical during the Practice sessions I am doing now.  On the day of the Eclipse then I will goto the moon which will get me close enough..

  Maybe AutoStarETX will provide a patch changing Plutos data to the data for the Sun to allow a goto.  O maybe provide data in a format I can put into the asteroid data base directly.    It will allow me to point at Earth II on the other side of the Sun.

  I hope some will find this information useful.

 

Ron

[Ron Hillstromb]

Hello all

 

An addendum to the previous post concerning the -.35 percent of sidereal motion of the Sun for Tracking.  Dick said the Sun doesn't follow a strait line across the sky.  If using a German Equatorial Mount (GEM) you may have to tweak the position of the Sun over time.

 

  Good Luck.

 

Ron