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Hi Leon,
Your image is hard to interpret. I presume the 60mmm poly pipe is either the polar axis on your tracker or somehow aligned with it.
There are two ways of interpreting your photo. If the centre of the rectangular camera frame is the tracker axis, by my assessment, you are pointing about 1 degree from the pole. If the centre of the circular vignette of the poly pipe is the tracker axis, you are about 30' off the pole.
It all depends what you want to use it for? I find that pointing a tracker within ≤5 minutes of the pole gives me dec drift free imaging with the sort of lenses I use with a tracker over several minutes. When within a few minutes of the pole, I can do exposures like the one attached, 4 mins unguided with a 135mm lens. As your polar alignment gets worse, the combination of usable focal length and exposure length both become shorter.
Do you have or can you attach, an optical polar finder?
If the device can have a small optical polar finder attached, there are two stars, mag 6.8 and 7.8 that straddle the SCP by just a few minutes. Shown in the attached chart. These can just be seen in a 10mm diameter polar finder in a small tracker and are an easy reference for accurate optical alignment. I've been using these for many years with great success.
cheers
Joe
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