Guidescope for LX200
I have an 8” LX200 and an ST-7E. I just picked up some Schuler photometric filters. The U and I filters are quite dark to start with and the CCD’s response in those parts of the spectrum is not so good either, so exposures need to be long. One of the disadvantages of having the guide camera built into the main camera is that it sees the same photons as the main camera - it looks through the same filter. So finding a guide star using the U and I filters can be challenging. I have a DSI on the shelf, and numerous spare small refractors, so why not use it for a guide scope.
The guide scope itself is a bit front heavy because its focuser is plastic and can not balance all the glass in the objective. On top of this, the guide scope must be pushed forward a fair amount in order to get it away from the eyepice of the LX200. In the end, it is not perfectly balanced, but close enough. Once the camera and dew-shield are installed, and another balance weight is installed, everything comes out pretty close.
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