Moonlite focuser The focuser on the 10" suffers from wobble. As the scope tracks across the sky the camera shifts in position. A solution is to buy a better focuser so I opted for the 'Moonlite' focuser. This is a Crayford design. I chose the version with the high resolution stepper motor drive.   The old focuser (with collimating plug in place)         The new Moonlite focuser. 4 new holes had to be made in the tube. The curve on the focuser base plate matches the radius of the tube exactly.         The camera in situ. It is held rigidly and there are no discernible 'wobbles'.         The Moonlite focuser has been in use for many months now, and I am delighted with its performance. I focus with a Bahtinov mask and Niels Noordhoek's Bahtinov Grabber and have not had any images spoiled due to poor focus. The graph below is a plot of the focus point with temperature. The relationship is clearly linear over the range of temperatures encountered so far. The temperature sensor in the focuser lets me know if the temperature has changed and it is easy to adjust the focus between exposures by 19 steps per degree.