View single post by Robert
 Posted: Sun Mar 31st, 2019 18:15
Robert



Joined: Sun Apr 1st, 2012
Location: South Lakeland, UK
Posts: 4066
Status: 
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OK, brief test this evening, really good sky tonight despite not going far.

The new wedge mount is excellent, needs finishing properly and details refining but it works a treat.  It's very solid and the adjustments work really well, way better than before, need much more practice but I took two series of exposures with and without the motor running.  I am currently processing the images as I type,  I took some without the motor running then I started the motor and all the stars stopped moving, but... they are giggling about.  I am not yet sure what's causing that, it may be the gear train again or it might be mirror slap shaking the camera arm.  The D800 mirror does seem to generate a fair old whack, at that magnification it must have some effect on sharpness.  I need to look into locking the mirror up.

I seem to have managed to find the celestial North.  I still haven't a clue how I did it, I wasn't sure which star was Polaris, which has been my problem before but I am gaining some understanding.  Polaris describes a circle around the celestial North axis, the trick is knowing at what point around that circle Polaris should be.  It relates to a 24 Hr clock, as you might expect...  This evening I wasn't able to see Ursa Minor, which would have clinched it.

I tried the Go-Pro Session but the images of stars in the dark were not bright enough.  It's fine in daylight but not in the dark.  I still need to make a small red LED lamp for the Polar Scope.  Will post some images in the morning.



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Robert.