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Rally the main problem is flexure in the ten position filter holder. The eight position filter holder with two filter wheels is far more rigid with two ZTA connections. Unfortunately I need ten filter positions for what I want to do.
FLI have offered to exchange the CFW but then I am limited to eight filters.
With a slower say F5 system the flex I have would not be as noticeable.
At the moment I have the usual LRGB gen II Astrodon with HA,NII,OIII,SII all 3nm and a 5nm Continuum filter. The last filter slot will most probably be a 5nm HA as this filter passes both HA and SII.
I do not ever need to do a meridional flip as the PMX will go more than two hours past the zenith. I have far less light pollution in my eastern and southern sky due to mainly extensive parkland in those two directions. It is terrible to the west. There is an Elm tree in this direction that acts as a light shade in summer.
My solution has the other benefit that I can easily adjust the camera position to get the camera sensor exactly orthogonal to the optic axis of the RH200. The factory alignment has the collimation spot on and coinciding with the optic axis of the RH200. The critical focus zone of the RH200 is very small less than a few micron. I am heating the RH200 to a constant temperature with five dew heater straps +- 0.1C 24/7 so focus does not change with ambient temperature. That is why it has the maroon towel wrapped around it.
The FLI PL1803 at 36.8x36.8 mm sensor with 52.1 mm diagonal is larger than the design criteria of the RH200 which is a 42mm circle. With 50mm square filters and properly aligned image train the images are good to the corners of the PL16803.
I use a 100ED for guiding with a lodestar. The side by side I have does not measurably flex.
My observatory is at the left and center of this image below.
Bert
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