Angled Polar scope?

[magician]

Has anybody tried to fit some sort of diagonal to the HEQ5 Polar Scope?there has to be a better way other than the hand and knees Yoga postion number 43,with dislocated neck option.C'mon fella's you know it makes sense I am only 5'6", you tall guys must be due for hospital treatment a couple of years down the road.

Cheers Frank

[magician]

Interesting observation, I posted this question on this forum yesterday,It has been viewed 34 times ,but no replies, I posted the same question on UKAI today , it has been viewed 64 times ,and I've received 4 replies,just an observation.

Cheers Frank

[geppetto]

That's cause they are cleverer than us over there Frank...

I understand your pain trying to look up the polar scope but haven't

put my mind to it yet

[magician]

Many thanks Geppetto, I was beginning to feel like 'A voice that cries in the Wilderness' and answer came there none,

Cheers Frank

[John]

I'm sure I read somewhere that you could perform polar alignment through your main scope - but I can't remember the method. I know the old Fullerscope EQ mounts used a polar finder scope that was on the outside of, but parallel to, the RA axis - that could be a small right angle scope I suppose.

I think it was Vixen that came up with the idea of a polar finder that was inside the RA axis - everyone seems to have copied this approach but they all seem to use straight through scopes.

John

[Kaptain Klevtsov]

I've bailed out of polar alignment so I haven't got an answer. My way to cure this was to bolt the things down to a big lump of concrete and leave them there. Drift alignment plus several tonnes of concrete works for me.

I'm sure that you could stick a Toucam where the sun don't shine, but I've not been tempted yet.

Captain Chaos

[Andrew*]

ugh. It's ridiculous. The effort of getting down there with minimum risk of arthritis and wet knees makes me pant, which clouds up the eyepiece, and puts off polar alignment for that night!!

Andrew

[Kai]

I just employ a Hobbit

No problem for me

[magician]

OK Fella's since you all seem to agree with me, lets cure the blumming thing! :)nobody goes to bed tonight without giving it some thought Yes?

Cheers Frank

[GazOC]

The problem with putting a 0.92" in diagonal on the end is that, aside from focusing issues, its another thing you'd have to ensure was correctly aligned.

How about using a camera connected to a laptop that had an application with the polar scope markings (adjusting for date/ time) running. You could line up the camera image of the pole star with the application software?

[Kaptain Klevtsov]

I liked the software idea that was reviewed in PA. You have a goto 'scope and a CCD camera, so it looks at what it can see, works out what it's pointing at, slews and does the same and then works out the error. It then scoots off to a bright star and puts a X on the screen. You wind the up/down and left/right knobs to put the star on the X and that's it done. Cool or what?

Drift aligning is the way to go though, and it's not too nasty, especially if you have a webcam and K3CCD tools to do the crosshairs bit.

http://members.aol.com/ccdastro/drift-align.htm was posted here some time ago. It's a good read, explains the whys as well as the hows.

Although I've never enjoyed looking up the polar 'scope, I've never had a problem with it. I expect it's easier for Fraccers as the mount will be higher off the ground for comfortable viewing.

Captain Chaos

[Vega]

I once tried my EQ3 polar scope way after twilight. A hilarious act which involved almost breaking my neck, attempting to shine a red torch down the top end of the scope to illuminate the diagram and not blind my view of polaris at the same time! NEVER AGAIN

At the moment I very lazily use my finderscope (tirelessly checked for alignment with scope beforehand) as I am vrey familiar with how far 3/4 of a degree is in it. Along with a polar alignment diagram printed from Polarfinder.

The webcam K3CCD Tools thing sounds like an intriguing godsend.... Im off to read that post!

ps I cant get K3CCD to work at the mo does it have an trial period expiary thingy on it ?

Vega

Vega

[MartinB]

My solution is to put a plastic sheet on the ground. Sit down and get in a half way comfortable position. No great drama there. Goto does make things easier - 2 star align then align on and centre it using the alt az adjusters. That gets you pretty close.

[Kaptain Klevtsov]

I cant get K3CCD to work at the mo does it have an trial period expiary thingy on it ?

Vega

On the download site there is a link to a page where you can get the license key as a download. Find that, click on where it says copy to clipboard, open K3CCD, go to the enter license key bit, paste and you're done.

[daz]

IIRC though CC, the free version does not include the drift align module..

I came across this though http://www.covingtoninnovations.com/astro/iterating.pdf which may (should) work for other makes other than those listed

[magician]

Thats a very interesing paper Daz,the bits I understand make sense, what I had in mind though was to use the polar scope, after all we did pay for it,the basic premise of the paper is something along the lines I was thinking a week or two back,thanks for the link.

Cheers Frank

[Kaptain Klevtsov]

IIRC though CC, the free version does not include the drift align module..

No it doesn't, but it does give you the crosshairs so that you can watch the star move, especially when zoomed in.

Intersting link BTW, yet another way to do it.

Captain Chaos

[Vega]

So many methods and no outright (and simple) winner. There must be some hardcore, filthy money instrument that can do spot on accurate alignment for you. When I say accurate I mean worthy for long exposure photography.

Maybe a giant rotate-able and retractable screen with Ursa Major, Cassioppiea, Polaris and the NCP imprinted on it which is put infront of the scope. Then some kind of laser guided detector mount with motorised atl/azm adjustment ???

Overrrrkilllll

[Kaptain Klevtsov]

It's called autoguiding Vega. You use a webcam to keep the stars in the same place by driving the mount in the appropriate direction. Pain in the butt, but necessary for high-resolution imaging.

Captain Chaos

[GazOC]

Even with autoguiding you'll still get trailing if you havn't aligned the mount properly.

[Kaptain Klevtsov]

Well, you have to get close at least. I assume we're talking field rotation kind of trailing Gaz?

Captain Chaos

[GazOC]

Yep. Although there are software 'get arounds' I beleive?

[MartinB]

So many methods and no outright (and simple) winner. There must be some hardcore, filthy money instrument that can do spot on accurate alignment for you. When I say accurate I mean worthy for long exposure photography.

Maybe a giant rotate-able and retractable screen with Ursa Major, Cassioppiea, Polaris and the NCP imprinted on it which is put infront of the scope. Then some kind of laser guided detector mount with motorised atl/azm adjustment ???

Overrrrkilllll

The techiest thing I know about is MaxPoint, Maxim and The Sky. That combination gives goto precision to within an arc second or two and can them be used to get a quick very accurate polar alignment. I have read how to do it and I think it is only quick once you know how and it needs the pro plus version of the sky which aint cheap (now there's a surprise).

Providing the polar alignment is reasonably close it takes a long time for field rotation to become evident. For me sky glow limits my exposure length long before field rotation - might be different when I get onto longer focal lengths though.

[Vega]

Yes light pollution got me at anything over 45 secs to 1 minute exposure. Then I bought an Orion Skyglow Filter. Check out the results of a single 3 minute exposure on M42 using it....

This is the RAW image, no alterations, you can see from the surrounding stars that my alignment wasn't great

http://www.mattastro.com/gallery/m42.jpg

So now I've kinda started listening to people who talk about accurate polar alignment