1. If I ever disagree with Dr. Stark, ignore me. <smile>
2. But, I think he's saying if you look at just the numbers in the guide log when calibrating, they're easier to interpret if the RA moves only in the x coordinate, and the DEC moves only in y. I agree with that.
But I never just look at the numbers, I look at the plot seen in Box number 2, which is now available as a menu item ("review calibration data") in PhD2. Maybe it wasn't in PhD originally?
Can anyone say?
In Box number 2 you can see the mounts behavior even though the RA and DEC motions don't fall along the axes, they're at an angle to it.
So, I think the important phase is "if you're not plotting".
These days, PhD2 plots the data for you, so you never have to be not plotting.
And "If RA+ moves mainly in x, does RA- move the opposite way in x? Does Dec move in y and not x? It should..." is talking about what happens if the lines are perpendicular. PhD2 gives you a numerical measure of how perpendicular they are.
My bottom line. I think the wording you're talking about was important in 2012, with PhD, which did not plot the calibration data. And, in 2021 (or whenever), PhD2 has made it obsolete by plotting the calibration data for you if you click "Review Calibration Data.
What do people think?
Edited by bobzeq25, 21 September 2021 - 06:59 PM.