Just wondering out loud here:
I normally guide with the Orion Mini Guidescope at 162mm. I've gotten about 1.2" RMS numbers consistently for a long time. I'm wondering if nothing else were to change except the focal length of the guidescope, say doubled to 324mm, would the RMS value show .6"? (PHD would have the appropriate numbers)
Is RMS similar to a percentage and wouldn't change? e.g. 8 of 10 is 80% and 80 of 100 is also 80%
Thanks for any insight!!