*
After a further couple of hours of testing I can confirm that the AWR drives ALWAYS needs the parking coordinates to be entered into the IH2 paddle every single time that the system is woken.
This seems completely pointless to me with a fixed observatory, fixed parking orientation, on a fixed pier. It just seems an unavoidable step before the system can be used as intended. Not only must the mounting be calibrated but SetP[ar]k must also be pressed before the telescope is moved under power. Otherwise it will never find its way back to the parking coordinates.
Manually moving the telescope is not allowed or the sky position is immediately lost. However tempting, the telescope must never be nudged nor slewed by hand! You would not believe how tempting it can be be given the glacial speed of movement under power.
Trying to press SetP[ar]k without first entering the parking coordinates [Calibrating] is denied. The IH2 screen will say "Not Calibrated!" Trying to enter a manually entered Goto via Coordinate to slew the telescope from the parking position is again denied. Not Calibrated!
I should mention that I don't have a celestial objects catalogue onboard because I am using a computer with planetarium software. It just seemed like an unnecessary duplication, at greater expense, when I ordered the AWR Goto drives system.
Once calibrated by entering the telescope's parking orientation: Horizontal East, weights down, the system knows where the telescope was pointing [is calibrated] and can then safely manage a slew. And, perhaps more importantly, can always return to "Base" on Home being pressed on the IH2 handset.
After a few frustrating attempts to send the telescope to align itself on the pole, lying over the PA, weights down, I switched off the system. Then Calibrated the parking orientation from scratch. [LST + 6 hours in RA, 0°,0',0" Dec.
I could then safely send the telescope to point at the Pole via a manually entered, Coord[inates] slew. Once settled on the Pole, pressing Home then reliably returned the telescope to its parking position. This action could then be repeated with close agreement on the coordinates each time.
Since I had deliberately left the laptop indoors for this exercise I was unable to confirm how ASCOM[AWR] and Cartes-Du-Ciel [Skychart] would manage. They do seem to be unable to read the AWR coordinates [as a team] from those I have already entered. So they too must, themselves, be set to the Parking position first with one proviso.
Unfortunately there is no useful object directly on the eastern horizon. So the nearest object to this position must first be found and used to calibrate [Sync] C-Du-C before proceeding. I had hoped the small variation from the true Eastern horizon wouldn't matter. C-Du-C offers no means to Sync [Calibrate] without an object lying under the cursor have been chosen. Moving the cursor to click onto Sync at the top of the screen will simply move the coordinates to Sync on the Sync button!
Unfortunately there is no useful object directly on the eastern horizon. So the nearest object to this position must first be found and used to calibrate [Sync] C-Du-C before proceeding. I had hoped the small variation from the true Eastern horizon wouldn't matter. C-Du-C offers no means to Sync [Calibrate] without an object lying under the cursor have been chosen. Moving the cursor to click onto Sync at the top of the screen will simply move the coordinates to Sync on the Sync button!
Even after all this, the planetarium system has been repeatedly and grossly in error in finding the Sun in a first slew. Which is my usual first target these days. I click the cursor on the Sun, in the on-screen chart and then hit Slew. The system will then send the telescope to completely overshoot by a mile in both Azimuth and Altitude! This is despite having being told exactly where the telescope is pointing before a single command is given.
This might well be an error in reading the Local Sidereal Time.[LST] This just seems a logical conclusion if the telescope repeatedly points an hour [or two?] beyond the Sun. In the sense that it is not just a completely random error of pointing.
I have repeatedly checked the parking coordinates shown in the bottom left corner of the Skychart screen before moving. If these agree with both the Equatorial and Altazimuth coordinates showing on the AWR screen then it has no excuse for overshooting. I must ALWAYS use the simple paddle to point the telescope at the Sun and then Calibrate with a Sync on the carefully centred Sun.
Much of this a is a repetition of the last post but I find it useful to confirm my findings so I can return to them as reference material once I have completely forgotten what I had found. [Memory of a sieve.]
As I write this at 18.30pm I am intending to go back out to the observatory, with the laptop this time, to test C-Du-C and ASCOM yet again. I need to confirm both LSTs match and that Skycharts shows the same initial [parking coordinates once calibrated.]
Having to re-enter the coordinates into the IH2 and then C-Du-C before I dare to move the telescope is a complete bore. The IH2 keyboard is fixed to the pier low over the laptop shelf and is not remotely user-friendly for entering multiple key strokes for RA and Dec. Three key presses per coordinate, plus enter, for AWR. Fortunately Skycharts can read the laptop keyboard. Even if it then completely ignores it!
I'm going back armed with the laptop: Wish me luck!
Later: AWR is showing LST +2 hours ahead of C-Du-C and an online LST calculator. I used C-Du-C to slew to Polaris after setting the parking coordinates. The telescope slewed well past the pole and the polar axis twisted too to put the weights perhaps 20° off. They should have remained quite closely aligned.
On pressing Home [for parking] the telescope went well below the horizontal and ended up pointing Northwest! The telescope cursor ring also showed well below the horizon in C-Du-C. Something is obvious very wrong. Who is winning the battle of the coordinates? AWR was fine on its own. Add ASCOM[AWR] and Cartes-Du-Ciel and slewing goes crackers!
I have just realized that forcing a slew to align with the Polar Axis is not a "real" sky coordinate. Just one relative to the supposed parking position and mounting alignment. Both are known and easily checked geometrical position in Altazimuth but nothing to do with the sky.
Providing I have northerly aligned the mounting well and quadruple checked the altitude of the Polar Axis then Polaris should not be a million miles [well, less than one degree] from aligned with the mounting. 0.66 degrees away amounts to a small circle 1.32 degrees around the true pole.
The Moon and sun are each about half a degree in diameter on the sky. Such a small deviation from polar alignment would not be visible in telescope pointing. So why is the telescope pointing 20 degrees away?
Later: AWR is showing LST +2 hours ahead of C-Du-C and an online LST calculator. I used C-Du-C to slew to Polaris after setting the parking coordinates. The telescope slewed well past the pole and the polar axis twisted too to put the weights perhaps 20° off. They should have remained quite closely aligned.
On pressing Home [for parking] the telescope went well below the horizontal and ended up pointing Northwest! The telescope cursor ring also showed well below the horizon in C-Du-C. Something is obvious very wrong. Who is winning the battle of the coordinates? AWR was fine on its own. Add ASCOM[AWR] and Cartes-Du-Ciel and slewing goes crackers!
I have just realized that forcing a slew to align with the Polar Axis is not a "real" sky coordinate. Just one relative to the supposed parking position and mounting alignment. Both are known and easily checked geometrical position in Altazimuth but nothing to do with the sky.
Providing I have northerly aligned the mounting well and quadruple checked the altitude of the Polar Axis then Polaris should not be a million miles [well, less than one degree] from aligned with the mounting. 0.66 degrees away amounts to a small circle 1.32 degrees around the true pole.
The Moon and sun are each about half a degree in diameter on the sky. Such a small deviation from polar alignment would not be visible in telescope pointing. So why is the telescope pointing 20 degrees away?
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