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Hi Dave,
I'm only 18 months into the hobby
Most times I get within 1 arc minute of PA which allows me to take at least 60 to 90 second exposures without star trails
I dont use a PC with guiding software or a guide scope etc.. old school
My kit - 150mm F6 reflector OTA
HEQ5 mount with Synscan
Canon 600D unmodified
Orion 20mm 70deg illuminated reticle eye piece used for alignment
PA Method
Forget compasses waist of time IMO , I use Stellarium software to find the noon meridian (time where sun is directly overhead and in line with SCP )
Level a 1m long x 12mm diameter piece of timber dowel at 90deg to the ground , driveway or paved area ( use string and weights as guy ropes to anchor the timber dowel at 90deg )
At exactly noon meridian time mark the shadow cast by the timber dowel at base of timber dowel and 500mm out along shadow ( line to be exactly in centre line of shadow ) This line will give you True South ( closer than any compass magnetic declination method - provided you are accurate with levelling and marking )
I set up my tripod mount along this line using a plumb bob and piece of aluminium angle ( once again as accurately as you can)
Level your mount
Set your latitiude ( I use a quality digital inclinometer ,not the crappy scale on the mount )
Balance your scope
Carry out a 2 star alignment as per Synscan manual ( use 2 stars same side of meridian not to far apart ) I used Hadar and Acrux last night
Then carry out a Polar alignment using method in Synscan manual section 11.3 page 36
Repeat 2 star alignment and polar alignment at least 2 or 3 times
You will get close to PA
Remember when using the Synscan to finish with the Up then Right direction keys when centering your stars
Also with the Orion 20mm illuminated reticle eye piece make sure you keep your head relaxed and still to ensure accurate alignment each time in the centre of FOV. I have astigmatism in my right eye so I use my left eye for star centering
I did struggle for months but take your time and be as accurate as you can and Im sure it will all work out for you
Best of Luck
Martin
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