ASIAIR+ and iOptron ZEQ25GT

Panama_Red

iOptron ZEQ25GT and Zwo Asiair +
These two work nearly flawlessly together. However, I can not get it to do a merdian flip. When the time comes for the flip, a message pops up indicating the mount is slewing but, nothing happens. The message timesout and indicates another flip attempt will happen in 60 seconds. Anyone have an idea why this is happening? Goto's and all other commands worh as expected.

PMTeam@ZWO

Panama_Red Please try the v2.0 beta version and upload the log, so we can try to fix it.

w7ay

Panama_Red When the time comes for the flip, a message pops up indicating the mount is slewing but, nothing happens.

By the way, this is actually "normal" for ASIAIR.

What is happening is that when it is time (according to the clock inside the ASIAIR) the target object has passed the Meridian, the ASIAIR will send a GOTO message to the mount.

If the mount's clock also agrees that the target is now on "the other side" of the Meridian, the mount will perform a Meridian flip, otherwise it will simply GOTO the object on the same pier side (i.e., make at most only a microscopic movement).

The message that you saw from ASIAIR simply means that it has sent a GOTO. It does not mean that the mount has actually slewed.

If the mount has really moved, ASIAIR will know, and then do the appropriate plate solving to recenter the object on the other side of the pier.

If the mount has not moved, a plate solve will indicate that the camera angle has not changed, and ASIAIR will then retry with the same GOTO command again after 1 minute.

ASIAIR will keep repeating the GOTO every minute until the mount finally performs a Meridian flip.

Now, if you are not properly star aligned, or your mount is not perfectly east-west leveled, the ASIAIR and mount "clocks" will be different. I.e., when ASIAIR thinks the telescope is pointed at the Meridian, the mount thinks the telescope has not yet reached Meridian.

Every 1 degree that your mount is not leveled against the horizon means that the "clocks" will be 4 minutes off in time . So, if your leveling is off by 1º, you may need to wait 4 minutes before all those GOTO commands finally succeed. 2 degrees off will cause you to wait 8 minutes in time, etc.

Thus, it is "normal" to have to wait a few minutes if (1) you did not do a multi-star aligment, or (2) your mount is not perfectly leveled, or (3) your polar alignment is off.

So, just wait, and eventually it will move. Eppur si muove.

Most people don't see this delay because they are already asleep, but again, it is "normal" unless you had done the above.

To compound the problem, ASIAIR also does not understand the concept of Daylight Saving Time. If the mount is observing DST, then you may need to wait an hour for the clocks to catch up. This is an ASIAIR bug that has existed since the very first version a couple of years ago. Since ZWO has not fixed it, people just resorted to lying to the mount that DST is not being observed. In this case, both clocks are off by 1 hour and everybody is happy (just don't time your dinner using the ASIAIR or the mount's clock in Summer).

So, be sure to also check the DST setting on your mount, and be sure to turn it off.

Fortunately, DST ends at the end of this month in Europe and a week after in North America (people in Arizona and parts of Indiana are lucky because they do not observe DST at all). And if DST is your problem, then it will solve itself in a couple of weeks time.

Remember though that even if DST has been disabled, you may still have to wait a couple of minutes (4 minutes for each degree that your mount is not leveled).

Chen

Panama_Red

w7ay
Should meridian treatment be "Stop tracking", "Telescope flip" or "continue to track?

Thanks

w7ay

Panama_Red Should meridian treatment be "Stop tracking", "Telescope flip" or "continue to track?

The mount's meridian treatment should be to stop tracking when it reaches Meridian.

Make sure it is not set to "telescope flip". Just let the ASIAIR control the timing when the flip occurs.

"Continue to track" can be dangerous for your instrumentation, if ASIAIR somehow "forgets" to stop at the Meridian. There was a bug not long ago where the ASIAIR "forgot" to flip at the "other" meridian for circumpolar stars (the Meridian between the pole and Nadir). Since ZWO does not do much regression testing, that bug might return, and "continue to track" will simply crash your instrumentation into the pier.

If you can, and if it is safe for your instrumentation, set the Meridian limit of the mount to a degree or two past the Meridian. When the Meridian limit is set to zero, the mount might stop before the ASIAIR thinks it has reached Meridian (e.g., if your east-west level is off), and the last frame before the ASIAIR stops at the Meridian will have trailing stars.

Chen

w7ay

Panama_Red Should meridian treatment be "Stop tracking", "Telescope flip" or "continue to track?

Oh, one more thing...

if you cannot set the mount's Meridian Limit to a minute or two after the Meridian (or if it is undsafe for you to do so), you can also ask ASIAIR (in the Meridian Flip Settings of the Mount Settings window) to "Stop tracking x min before Meridian" and giving that parameter a couple of minutes.

(The "min" stands for minutes of time.)

This way, ASIAIR will stop taking images, do a final plate solve, and then stop tracking x minutes before the mount reaches the Meridan.

I.e., time is relative, and all you are doing is to time shift both the mount and the ASIAIR by x minutes.

Doing this will also be safer for your instrumentation, since the ASIAIR will stop the mount even before the mount has reached Meridian.

Just remember that the mount must not stop itself before ASIAIR can take that final plate solve. I have seen people complain that the final plate solve fails -- and this is because the mount has stopped before ASIAIR has a chance to perform that last plate solve, causing trailing stars that will not plate solve.

I do not use auto meridian flips myself -- I normally pre-flip my mount manually to a point in the sky that has already passed Meridian, and use the dead time while waiting for the actual target to pass Meridian to do some Bahtinov refocusing on the other side of the pier. Howver, when I did use auto meridian flips, I had set that "Stop tracking..." parameter to 5 minutes (a little bit more than 1º of hour angle).

Chen