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[IvanT]

This may be silly, but when we get instructions like "pick a star in the east" and "polar alignment is too far west" particularly when reading about drift alignment, are we typically talking about east west as on the celestial sphere (i.e. reversed) or are we talking about what we normally think of while standing on our little blue marble?

Sorry if that's laughable, but I thought it better to ask than assume as drift alignment is still giving me problems and I suspect instead if correcting the drift I'm compounding it.

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[brantuk]

When you look up at the sky you're usually looking south cos thats where all the action is with the planets. But it puts East on the left of the sky and west on the right. Looking at a map it's the other way round - just have to conciously reverse the way you think about it

[IvanT]

When you look up at the sky you're usually looking south cos thats where all the action is with the planets. But it puts East on the left of the sky and west on the right. Looking at a map it's the other way round - just have to conciously reverse the way you think about it

Yip, I get that bit, what I'm not sure about is which is being referenced when east west is included in instructions, i.e. if someone says "now pick a star low on the horizon in the east" do they really mean celestial west? I guess my question is do astronomers and their guides always refer to celestial coordinates?

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[brantuk]

Ahhh I see what you're asking - well I don't know about everyone else but if I'm looking at polaris from the UK - then east is on the right cos I'm looking north. If I'm looking at the southern meridian then east is on the left. It's in the same place but depends which way you're looking.

Going with celestial coords - then RA starts in the east and travels in time over to the west. But it depends which way your looking and which hemisphere you're in as to where it is (L or R). I guess you just have to get a feel for it.

Here in the uk we allways polar align North then generally swing the tube round to the south to start observing. East and west are still in the same physical place though. That's the way I look at it

[brantuk]

""now pick a star low on the horizon in the east" do they really mean celestial west? "

To me this would be left if I was facing south - or right if I was facing north - celestial east is still physical east if that helps

[barkis]

Imagine the polar axis of your scope, pointing to Polaris, the general direction of the Celestial Pole. If your star drift indicates that your Polar axis is too far West of the pole, then you have to move the mount in azimuth to the East which is a clockwise direction whether you are facing South or North. If the drift indicates the mount is too far East of the Pole, then you move it in azimuth to the West, which is anti clockwise.. Too far above, and too far below, need no explanation as to the direction.

These incremental movements need to be small ones, as the corrections you make, will soon show positive results if you are doing it right.

The star drift in your scope depends on the scope you use.

It can be confusing when a star drifts off the crosshair. You can easily ascertain which direction it has drifted. by nudging the scope up or down.

Ron.

[IvanT]

Thanks guys, think I've got it now, next clear night will tell. I suspect my adjustments have maybe been too large.

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