Solar drift alignment during the day ready for night session?

[NickK]

Has anyone set their scope up for solar viewing (i.e. filters etc) then use the sun as a drift alignment target through the afternoon?

I was thinking about this at SGL6 but didn't have any solar filters - use the vixen for solar during the day (with 910mm fl it should make drift alignment very accurate) then switching to the pentax at night.

Switching scopes would change the scope alignment with the mount, true, however the mount's polar alignment should still remain.

[Bizibilder]

I would be concerned that the Sun moves over a degree a day E-W against the sky (roughly 360/365 degrees) and a little N-S - I must admit I'm not sure if this would cause problems over a short time?

[NickK]

Ahh good point - yearly cycle!

[Merlin66]

Works pretty well.

I have an HEQ5pro mount which I use for spectroscopy at night and solar (SM60/ED80) during the day.

I usually just plonk the mounting in the garden roughly aligned and use the slight drift in dec during solar observing to tweak it to give good tracking. Then at night, if nothing has moved it's ready to go.

[NickK]

Just looked at the Synscan handset of the EQ6, it has the following tracking settings:

* sidereal

* PEC+sidereal

* solar

* lunar

So in theory using the solar tracking could be used for the solar drift alignment.

[lukebl]

So in theory using the solar tracking could be used for the solar drift alignment.

Not entirely accurate. The speed of the sun's apparent motion changes throughout the year due to the earth's variable speed in its eliptical orbit (i.e. fastest when at perihelion, slowest at aphelion)

[NickK]

I'm making the assumption that by selecting solar it would vary the rate of tracking by the date. The mount certainly makes a different sound.