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Bit of a report on the scope.
I have been having all sorts of trouble trying to eliminate flex and star shape problems. My general motto in the past has been to use screw fittings on all the adapters I use (unless there is a dovetail zero tilt connection). I went with the adapters supplied by OOUK. The adapter from the Atlas that holds the corrector is a reasonably tight fit but has some movement which is supposed to be supported by nylon screws. This system cannot be used reliably to prevent flex or even get the star shapes right in every corner. At least that is the case in my experience. If you move the screws one way the stars go haywire in another corner.
Then the screw threaded adapter made by OOUK from the corrector to the QSI, was firstly too long, secondly the screw threads were not centred to each other, and then each set of threads were not parallel ( a friend of mine who is a machinist said that the each axis was out by over five thou. This means that each time you screw the adapter around by as little as an eighth of a turn the adapter will produce a slanting projection of the correction and that means stars will be not corrected properly and produce poor star shapes.
So I have had two more adapters made up by Precise Parts. One I am waiting on and the other I have already received but needed the thread depth adjusted due to OOUK drawing suggesting that correction is 79mm from the centre of the external rear element and that is level with the outside of the corrector housing. It is not level and in fact almost 1.5mm lower than the housing edge. I am now near the correct position for correction. The other adapter is to replace the adapter which holds the corrector. It will screw thread into the back of the corrector. With any luck this will be the end of these issues and allow me to get on with imaging.
A frustrating experience so far. If anyone asks me if I would recommend a Newtonian, I will certainly caution them about the issues I have faced with both Newt's I have owned in recent years.
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