June the 8th dry run

[Rocket Pooch]

Hi,

Now I have my solar film etc, I have a couple of questions.  

Firstly (don't laugh) does the Sun track at the same rate as the stars?  Will I be ok with a normal slew rate on my telescope?

Will notmall Polar alignment be ok for this?

Also has anyone tried to autoguide on the sun?  I was thinking of pointing the LX90 at it and autoguide through my SkyWatcher 80mm?  I believe this should work providing I use the LPI?  Anyone done this sort if thing before?  I was wondering if there was enough detail on the Sun for this to work?

Lastly, anyone fancy a dry run down the field later this week 4am ish to see where the sun will rise?

Bye

[Rick]

Firstly (don't laugh) does the Sun track at the same rate as the stars?  Will I be ok with a normal slew rate on my telescope?

Near enough. The difference is about 4 minutes in 24 hours.

Will notmall Polar alignment be ok for this?

Yes.

[Greg]

Yes, agree with rick about one degree of celestial motion per day. It should make any difference for the type of observation you are doing.

[Rocket Pooch]

Ok, thanks for that, so all I have to do is setup the kit and wait, in the, field for dawn.

[Mike]

Who's Dawn?!

If we get down to the field early enough on the obs. session the day before we would see were the sun would rise nicely ! We could always go back to the pub of course (presuming it isn't cloudy and we can SEE the sun of course).

[JohnP]

OK -So what's the plan for next Mon/ Tues - are people planing an all night session at the field or is it meet at the pub & head on down after closing time? Also, I've never been to the field before - Is there any possibility of having access to 240VAC? The problem I have with my TAL is that the motor is a 12VAC 50Hz - If no mains is available I'll have to fork out on one of those DC to AC converters that maplin sells & get a 12VDC car battery (or use the one in my car I suppose).

Thks,  John

[Rick]

I don't think there's any 240V AC in the field. There's a "normal" observing evening on Monday, so, sky being clear, folk will be going to the field around sunset. Some folks will stay overnight. Others will retire to bed and return around sunrise. All assuming it isn't chucking it down, of course....

[Mike]

John, you'd be better of with a low voltage 12v ac to 12v dc convertor as you will lose power using the 240v convertor. Can't it also take 12v DC??

[Ian]

if you're feeling brave, you can get 12V AC out of an 12VDC to 240VAC invertor if you tap off before the transformer.

All usual disclaimers apply, including the fact that I've never actually tried it, but if you want me to, I can take a look at the invertor I have at home.

[JohnP]

Unfortunately, the Tal-2m has an AC motor that runs off 12V, 50Hz for driving the RA axis. It won't work off 12VDC. I actually made a little invertor from a diagram I found on the web that converts from 12VDC to 12VAC however, I won't have time to install it before Mon/ Tues. I figured the easiest solution would be to buy a 12VDC to 240VAC invertor from Maplin - this way I can plug in the 240VAC to 12VAC transformer that I currently use (came with the scope) I could also use it to plug in my laptop when the batteries die. It'll also be useful if I ever take the kids camping sometime in the future.....!

Thks for all your help - John

[Mike]

John, I have one you can borrow if you like as i won't be using it.

[JohnP]

Hi Mike,

That would be excellent thanks - John