How to convert a “weak mount” into an appropriate mount by means of TPoint & Star Tracking
Starting point was the available German Mount SP-DX (VIXEN) which is known to be a good one in terms of imaging until aprox. 8 - 10 kg of load.
Since in the worsed case my equipment has a weight of more than 20 kg it was necessary to improve the mount considerably in terms of pointing acuracy as well as perodic error.
The pointing accuracy was improved by TPoint which takes care of bending errors etc. while the genuine total periodic error of 43 arcsec was drastically reduced to 2.7 arcsec (i.e. 6.3%) by the method of “Star Tracking” using a cheap guide scope in conjunction with SBIG’s ST-6 CCD camera. The other beauty of the ST-6 compared with the ST-4 camera is its huge FoV (53’) which takes care of more than enough guide stars in any direction.