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Going to do my first Drift Align...


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As the pier has been installed and the moon is extremely bright I've decided to do a drift align tomorrow night (assuming the forecasts are correct). I've been going through the various guides and they have helped immensely, I have a couple of questions I hope someone can help me with.

For Azimuth alignment, I should be pointing the scope in the south and as close to the equator as I can get (with some margin). For me this is going to be about 20 degrees up, which I gather isn't great. This is due to the top of houses being at around 10 degrees. Is this going to be a major problem?

For Altitude alignment, I should be pointing the scope East or West (West for me) and 25-35 degrees above the horizon. Due West I can see almost down to the horizon so the 25-35 is taken from the guides.

Any comments greatly appreciated,

Pete.

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Have a look on Stellarium and you can see the zero equator line going across the sky from east to west, if you press the . key it will highlight it in a slightly different shade of blue.

You need to drift on stars somewhere near this line for best results.

The South one should be well above houses around 0 dec. 

I find it best to start an "hour" to the east of the meridian when aiming south as you don't want it doing a meridian flip in the middle of drifting, the Moon might be a problem.

You don't need a "named" star just aim in the general direction to find one.

Are you using an illuminated ? I've  used the PHD drift aligning tool which works well once you get your head round it :)

Dave

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50 minutes ago, Davey-T said:

Have a look on Stellarium and you can see the zero equator line going across the sky from east to west, if you press the . key it will highlight it in a slightly different shade of blue.

You need to drift on stars somewhere near this line for best results.

The South one should be well above houses around 0 dec. 

I find it best to start an "hour" to the east of the meridian when aiming south as you don't want it doing a meridian flip in the middle of drifting, the Moon might be a problem.

You don't need a "named" star just aim in the general direction to find one.

Are you using an illuminated ? I've  used the PHD drift aligning tool which works well once you get your head round it :)

Dave

Oh that's interesting, so the equator it's talking about for Azimuth is the celestial equator? I had wrongly thought horizon. That makes life much easier as it's much higher.

I assume an hour west of south isn't an option? This would keep me clear of the moon.

Am I using an illuminated what?

Thanks for your help on this.

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5 minutes ago, Peje said:

Oh that's interesting, so the equator it's talking about for Azimuth is the celestial equator? I had wrongly thought horizon. That makes life much easier as it's much higher.

I assume an hour west of south isn't an option? This would keep me clear of the moon.

Am I using an illuminated what?

Thanks for your help on this.

You can start west of the meridian for azimuth adjustment and use a star on the western horizon for altitude adjustment makes no odds.

I use a 12mm illuminated reticle just an eyepiece with illuminated cross hairs, you can line the the cross up parallel to the movement of the scope then see which way the star drifts.

You can use the ST80 and QHY with PHD Guide assistant instead.

You only need to monitor north / south movement.

Dave

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2 hours ago, Davey-T said:

You can start west of the meridian for azimuth adjustment and use a star on the western horizon for altitude adjustment makes no odds.

I use a 12mm illuminated reticle just an eyepiece with illuminated cross hairs, you can line the the cross up parallel to the movement of the scope then see which way the star drifts.

You can use the ST80 and QHY with PHD Guide assistant instead.

You only need to monitor north / south movement.

Dave

So you mean i can just swap S & W but follow the other guidelines?

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29 minutes ago, Peje said:

So you mean i can just swap S & W but follow the other guidelines?

You can swap east and west horizons and east and west of the meridian.

Do you understand the principal of drift aligning  or are you just following the instructions ?

Dave

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6 hours ago, Davey-T said:

You can swap east and west horizons and east and west of the meridian.

Do you understand the principal of drift aligning  or are you just following the instructions ?

Dave

I'm simply following instructions if I'm honest, I would expect the theory wouldn't be too difficult to grasp...I just haven't tried it

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If there was a star on 0 (which annoyingly there doesn't appear to be) and you aim your scope at it as it rises in the east you should be able to rotate your scope in RA and follow it without adjusting the dec .

If the star gradually rises "up" in your scope then your mount is aiming too low so you raise the dec adjuster to compensate.

You need to figure out which way is up depending on you scope configuration and realise that up is not vertically up but actually north towards Polaris.

Similar when aimed south at zero the star goes "up" you adjust azimuth bolts to bring it down.

Dave

Here's the DARV method Freddie mentioned.

http://www.cloudynights.com/page/articles/cat/articles/darv-drift-alignment-by-robert-vice-r2760

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Well I spent about half an hour at it,

Azimuth got to +/-1" within ten mins, Altitude was a bit more tricky and after twenty mins I retired hapy with +/- 2". Overall I'm pretty happy with that.

Now even tho the moon is up I'm going to point the scope at M106 and let it run til 4am while I get some much deserved sleep.

Thanks to all who commented, as always SGL saves the day!!

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