Rosliston Astronomy Group


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Geoff Dryland


Gradually getting there!! (My re-collimation - see previous entry when I imaged NGC 7000 in Ha)

Last night's image of the Witch's Broomstick. Just 3x6minute images in Ha.

Big improvement over last attempt at collimating the Takahshi 180 Epsilon. Still not quite there as the stars, although better (spider spikes are even), are oval on the North/South axis. This is not tracking error as this is occuring on the E/W axis, so it must be that the secondary mirror is still rotated a fraction. The laser shows it slightly off centre. Have to wait for Lee to get back from holiday to sort this one out.

Any other suggestions welcome. Note that since I took this image 7/8/15, I have also taken another of the same object 8/8/15.


NGC6960 070815
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