Skywatcher initial scope positioning before alignment

[Ajohn]

This question relates to an EQ3 Pro Synscan but probably relates to all Synscan mounts.

I had the impression that they all started by putting the peg on the tripod north and levelling it, aligning one way or the other and pointing the scope roughly at polaris then going through the goto alignment routine. I'm not sure if I have the correct manual.

The mount I have bought suggests otherwise some one has put alignment marks on that suggest that the scope is pointing east or west, rather roughly as the scope wouldn't be horizontal. This leaves me wondering if there is some way of persuading it to work that way? It is has some advantages,

Suppose some might wonder what advantages. So

When I mount a telescope on this type of mount I always turn the mounting plate so that it is more or less horizontal with the clamp screws pointing upwards. That way it's easy to get the scope in and it's relatively safe even with the clamp a little loose to allow it to be balanced.

It seems a little silly to then have to swing it up to point at Polaris. Worse still it's dead easy to set the scope level in this position with a spirit level. As the scope is a lot easier to sight along than the mount it's also easy to align it east west with a compass which in turn will align the mount to the north. It's even possible to roughly estimate true north. Eg where I am at the moment true north is 1 1/2 degrees off magnetic. At another site I observe from it's 2 1/2 degrees. The spirit level is likely to set the scope horizontal to better than that.

I have used mounts that align like this and it can be surprisingly accurate so wonder why on earth any one produces scopes that have to be set up differently.

John

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[Lowjiber]

Put the az scale to zero; level the tube, and point the scope as close to true north as possible.  Now, do an alignment (2 star).  It will be a bear, but you can do it.  Once you're done, put the scope in "park" and shut it off.  Now, do another alignment... it will be quick and accurate.

[ronin]

I suspect it is a case of someone trademarking the alignment process, namely Meade.

Meade have as best I know always had "Level and North" as their start position, and back then I half suspect they took out some sort of "patent" or such like on the term and method. Meaning litlgation if someone else tried it.

So Skywatcher/Celestron/Synta have to have something different.

The Meade one is simply a virtual star as the initial position.

But it allows the presumption of a start position so that the scope can make a good guess at where the first real alignment star should be. On the others I think you have to point the scope at an agreed star first - this is then that scopes start point after that the mount takes over.

Never quite known why the Skywatcher etc ones do not start with the scope centered on Polaris, sort of Level and Polaris, that would be a simple and easy initial position.

[happy-kat]

Well my skywatcher after programming in the location previously. On next use set tripod up/level point the telescope at your altitude (polaris really and same as saved settings) and then turn the mount on.

It will now track or do more and align stars to use go to

[Ajohn]

Must admit I am a bit of a Meade man Ronin. The first goto I really used was a Meade gem fitted with their 5" F9 APO. Dark site and I used the scope rather than the finder to try and align it. So many stars in view I had no chance of telling which was which so pressed ok and same with the next. It was close enough to use.

Vixen used level and east west orientation on the gpdx s 2k if I remember correctly. Also align on anything, moon, planet, fuzzys.  Personally I see that as very user friendly allowing some degree of alignment in any old conditions.

I don't think that Meade and others use a virtual star. It more like a fixed initial reference that doesn't move - like Polaris nearly is. I haven't fully digested the manual but wonder if park could be used to achieve the same sort of thing but really it would be best to have it in the controller. That assumes park can be customised but the previous alignment correction factors are probably retained so it wouldn't be ideal.

John

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[Cornelius Varley]

The normal "home" position for a Skywatcher eq goto mount is counterweight bar pointing straight down and telescope pointing at the north celestial pole. This gives the handset a known start position for finding the first alignment star. The home position can, however, be customised to suit your own personal requirements, such as if you have a permanent setup ie observatory and the telescope needs to be parked horizontally so that the roof can be closed.

[Ajohn]

Subject to reading again it looks like the alignment star filtering is easier to use on the alt az versions of these mounts. Suggesting that people who buy equatorials don't have excessive light pollution in certain directions where as alt az people will have.

Here's me  with the S in front of B'ham in my location signature so Skywatcher seem to think I should only buy an alt az mount. North for me from the garden is something of a no no. For others it might be the same  in any direction.

Weird really as the software for this facility seems to be in all of the handsets.

John

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