leveling the RAPAS on Mach2


weihaowang
 

Hi,

I understand that Mach2 can be used without leveling the tripod. This is great for us, since our tripod cannot be adjusted and therefore cannot be leveled.  However, this will create a problem for the polar alignment.  We purchased an RAPAS, and it's my understanding that using it requires the tripod to be leveled.  I can of course use a PoleMaster or drift alignment without worrying about leveling, but I like the quickness of a polar scope in the field.  So I want to find a solution.

A question here is whether I can assume the top surface of Mach2's RA motor box to be perfectly aligned to RAPAS?  

If the answer is yes, then a simple workaround would be to use my iPhone's inclinometer on the top surface of the RA motor box to measure the tilt, then do the necessary compensation in RAPAS.  I think iPhone's inclinometer is good to a degree.  Given the distance between Polaris and the pole, a 1-degree error in leveling would translate to 1 arc-minute of polar alignment error, which should be good enough for my imaging.

How do you think about the method above?  Or do you have any other suggestions on using Mach2+RAPAS on a unleveled tripod?

Cheers,
Wei-Hao

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