| rnabholz |
| (scholastic sledgehammer) |
| 05/09/06 10:44 PM |
|
Re: Degree Circles
|
Quote:
I just did some calculation on delta between leveled and full swing platform. It does not work. Because the delta is not a consistant number. The object closer to Polaris for example will have a different delta from an object away from Polaris.
I am curious, as I suggested in the earlier post, I suspect that as you move toward one of the multiples of 90 degrees - 0 - 90 - 180 -270- 360 you reduce the error. Stated another way, at 0 degrees no error - increasing error to 45 degrees - then decreasing error to 90 where it is minimal, or even eliminated. Continuing the same way every 90 degrees all the way around.
Does this make sense to anyone but me?
Quote:
In regard to your inclinometer, I assume when you mount the inclinometer on the tube - it has to be vertical in order to get an accurate reading of the altitude. But . . . when you have a platform swings all the way . . . the inclinometer is not necessarily vertical anymore.
So even using an adjustable mounting, there should be a way to compensate vertical axis.
The RA and Dec method is even more complicated because dobsonian has only two UN-adjustable plane (vertical and horizontal) With RA and Dec, you need to have a 3rd axis in order to make the 2 planes coincide with the true North (Polaris) . . . like the the equatorial mount. . . . Unless I am wrong . . .
Have fun tinkering . . . I am going to sleep on it again . . .
Ridwan
Regarding the inclinometer, the analog unit would be susceptible to mechanical error- the indicator would rub on the housing. I am not sure about my electronic unit, I haven't tried it in anything but a normal attitude.
Have to give that a try.
Interesting to think about. Thanks