Ok fair question here - to track the sun should you use solar rate on a EQ mount?

[h0ughy (David)]

to track the sun during daylight hours should you use the solar rate or sidereal , I know its not lunar ??

Any help on this one people?

[sheeny (Al)]

The fair answer, I believe, is "yes"... you should use solar rate.

Al.

[[1ponders] (Paul)]

Yes and no h0ughy

Yes, using it will keep you at the same pace but it won't help you track it exactly. Your polar alignment is aligned on the motion of the stars across the sky, ie follows the Celestial equator 0 Dec. The sun follows the ecliptic across the sky which only matches the celestial equator at the two equinox.

So no matter how good your solar rate is on your eq mount you will still get dec drift unless you drift align using the sun at midday. The main problem will be in azimuth adjustment. I think

[[1ponders] (Paul)]

I was tracking it yesterday on a well aligned scope and it took quite some time to show obvious movement by eye at 60x mag but there was definately drift.

[h0ughy (David)]

Originally Posted by [1ponders]

Yes and no h0ughy

Yes, using it will keep you at the same pace but it won't help you track it exactly. Your polar alignment is aligned on the motion of the stars across the sky, ie follows the Celestial equator 0 Dec. The sun follows the ecliptic across the sky which only matches the celestial equator at the two equinox.

So no matter how good your solar rate is on your eq mount you will still get dec drift unless you drift align using the sun at midday. The main problem will be in azimuth adjustment. I think

that means i will have to set up while the stars are out then wait for sunrise for the mercury transit

[[1ponders] (Paul)]

Weren't you going to set up at sunset the day before, get in a bit of evening photography and then catch the sun

What are you going to be doing that will need such accurate tracking h0ughy?

[h0ughy (David)]

Originally Posted by [1ponders]

Weren't you going to set up at sunset the day before, get in a bit of evening photography and then catch the sun

What are you going to be doing that will need such accurate tracking h0ughy?

Umm interviews live on radio and the public, i want to set the camera up and take shots for a time lapse for the whole transit, so I want it to track reasonably well, unless i change my mind and go completely ad hoc (very normal for me).

Setting up the eq6 no 1 with the meade 12" and solar filter (nice and big so the public and Media will be impressed ) and the real deal wit hthe PSt piggybacked on the 5" Inites scope on the second EQ6 if I get lucky I might even get Mike to show me to set up the toucam I got off Striker and use that on the PST!!!

Ahh should be grand, i will even have the portaloo up!

[RB (Andrew)]

Originally Posted by [1ponders]

What are you going to be doing that will need such accurate tracking h0ughy?

I'm wondering the same thing Dave, why do you need such accurate tracking?

EDIT: Doh, mental note: Read the whole post before replying.

[[1ponders] (Paul)]

There is a way you can do it h0ughy. There was a lovely little sunspot on the face yesterday. You may be about to pick that up on the ToUcam and autoguide on it

Now remember if you are going to view the sun with your 12" you will need about a 40mm eyepiece to get the whole of the sun in the field of view. A 35mm Panoptic only just makes it on a C11.

[h0ughy (David)]

Originally Posted by [1ponders]

There is a way you can do it h0ughy. There was a lovely little sunspot on the face yesterday. You may be about to pick that up on the ToUcam and autoguide on it

Now remember if you are going to view the sun with your 12" you will need about a 40mm eyepiece to get the whole of the sun in the field of view. A 35mm Panoptic only just makes it on a C11.

Paul i have a 24mm meade uwa 5000, and a 34mm swa 5000 both fit the entire moon in the view


btw the toucam will be on the PST

[CoombellKid]

David,

If your only imaging for stints over a few hours, I would of thought the suns
movement across the celestrial sphere would be minimal scarcely enough
to register. I have had the PST out on the EQ5 and are managing to track
the sun pretty good for extended periods of time. I dont see why your EQ6
couldn't track it nice for quite some time if you wanted it to.

regards,CS sunny transit days

Rob

[CoombellKid]

Originally Posted by Rocket Boy

EDIT: Doh, mental note: Read the whole post before replying.

Me Too!

Rob

[h0ughy (David)]

thanks for the advice guys

[seeker372011 (Narayan)]

for whatever its worth I use the solar tracking mode on my CG5 and have kept the sun on a touCam chip of a PST fo several hours

only problem is you only get a portion of the disk with a ToUcam-wouldnt you hate to be imaging the wrong end of the sun eh? at firrst contact,( which is what happened to me aduring the transit of Venus ) and you need to be sort of close to polar aligned to start with