PA with a laser ?

[Guest peepshow]

Since on my other thread I spoke of about adding a green laser to my 15 x 75 bins I have bought another laser.

Although I haven't yet tried this I am going to fit this laser parallel to my barn door tracker RA axis. 

 

Knowing at what time Polaris will be exactly to the north, south, east or west of the celestial pole I can direct the laser at Polaris and then move my RA axis, (by estimation the required 1.5 moon diameters) either  south, north, west or east of Polaris.  

 

This should be a good starter for better alignment later on.

 

The estimation can be refined by cutting a piece of card whose width, when held at arms length up to the moon, is 1.5 times the moons apparent diameter.  This card is then used to help get a better laser

1,5 moon diameters.

 

Maybe someone can  develop this for a quick technique for PA.? ...........

.....known as LPA (laser polar alignment)

 

[Tweedledee]

Hi Richard,

I think you are confusing arc minutes and arcseconds. Polaris is about 1/60th of your 1.5 moon diameters from the NCP.

The laser beam width will probably subtend a few arc minutes in the sky, so will not give much pointing accuracy.

[Tweedledee]

Sorry, my mistake. I'm getting confused. Your distance is correct but the laser is too wide to point accurately.

[Guest peepshow]

OK Pete, on all that.  But somehow or the other, it would be getting into this century if

a laser could be used. 

 

If clouds permit I shall be out tonight testing the width of my laser on Polaris, to see how

1.5 moon diameters looks etc. 

 

A thin aiming tube may help.  ( length and dia of tube to give 1.5 moon diameters when

looking down it, side to side as it where.)

 

Maybe two lasers bolted, say 12 inches apart with their beam angle  crossing???

(The angle set up in a field in daylight.)

I still have a gut feeling for all this.  ......

.......maybe a length of cat gut pointing at Polaris?    

 

If too may try this any aliens on planets near to Polaris will be saying, "Wot's those b****y

green lights down there?" 

Edited November 7, 2013 by peepshow

[Big Al]

 

If too may try this any aliens on planets near to Polaris will be saying, "Wot's those b****y

green lights down there?" 

...plus close attention from all flights heading south from EMA...

[xanthic]

...plus close attention from all flights heading south from EMA...

 

Keep an eye out for those blue and yellow helicoptors too...

[Guest peepshow]

Yes guys, careful with planes but not too many helicopters around my neck of the woods at night

and laser only on in short bursts.  

 

Did you see that helicopter green laser show when Mabarak was overthrown ?

 

Dozens and dozens of  lasers shining on it !

[Big Al]

If you see a 'coptor at night, it's a pretty safe bet it's the Police one. Even the Air Ambulance based at EMA doesn't fly at night.