Agree Raymo,
I know I was sloppy with my alignment stars, calibration stars & to be honest with my PA... I was getting frustrated with my earlier dramas & I let it get to me & then got sloppy..
Interestingly, the numbers in the handset looked pretty reasonable but, the pictures tell a very different story.. that's why I took them because I knew they would show the actual results rather than just theoretical numbers.
I have an f6.3 & an f3.3 reducer for the meade, picked them up secondhand quite cheaply. The f3.3 is no good for the DSLR, spacing is around 35mm which is shallower than the sensor depth but, it does come to focus with my ZWO.
Next time out, I will apply the lessons I have learned & be more critical & precise with my alignment, calibration stars & PA & then probably do a second routine to refine the errors down. As stated in my first post, I should know better.. when I got the SCT I was sloppy with setup & alignment which ended up in a frustrating night of missing gotos, when I focussed on the little things & got them right, the nights viewing was much more enjoyable as I was hitting gotos in a 12mm EP....
It's all in the initial setup; a lesson I really should have etched in my brain by now...
I did notice when mucking around with my camera setup today that it wasn't as 'tightly mounted' as it should have been & it was rotating a little, that might account for some of the movement but, I suspect it has more to do with the PA.. I have since rejigged the camera mount & inserted a thin washer which was just enough to tighten it all up & still have the camera pointed forward...
Cheers
Quote:
Originally Posted by raymo
Firstly, by all means keep using your SCT, but you won't get shorter exposure times, at f/10 it is very slow photographically. Being alt/az you are limited to 15-20 second subs before star rotation rears its ugly head. An f/6.3 reducer
would help things immensely, but are not cheap.[assuming that you don't already have one.]
It would appear that your polar alignment is not good[judging by your pics],
or something is slipping during the exposures.
Using the 55-250mm lens the stars should be round using 40-120sec subs.
raymo
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