Input target coordinates directly

stubblejumper

Because of camera/scope constraints, I cannot capture M31 without creating a mosaic. I have selected two stars to be the anchor points but I don't think ASIair Pro supports the Hipparcos catalog. I know the JNOW RA and DEC data for these two stars. Is there any way I can enter the RA/DEC coordinates?

w7ay

stubblejumper Is there any way I can enter the RA/DEC coordinates?

A small popup GOTO window appears after you connect the ASIAIR to a mount. This is the window that has the four directional slew buttons and the slew speed slider.

Tap on the RA field in that window and the GUI to set the RA appears. Tap on the DEC field to change/set the Declination. After setting the RA and Declination, tap on the green GOTO button.

After setting the target coordinates, you can also save the "current" coordinates so you can reuse the same target in the future. Just follow the usual procedure that you use when saving other targets.

Chen

viperduude

w7ay
Does ASIAIR Pro expect J2000 or JNow coordinates?

stubblejumper

Thanks Chen. I hope to use it tonight,

Don

w7ay

viperduude Does ASIAIR Pro expect J2000 or JNow coordinates?

Since the beginning, ASIAIR had used JNOW, which led to lots of complaints. I don't think that it has been changed to J2000 yet.

Since spacecrafts like to use Capella for navigation in the good old days, here is an example of the coordinates for that star in the current v1.8 (build 5) beta release of ASIAIR (released this morning):

RA: 05h 18m 18s, Declination: +46º 01' 21"

J2000 coordinates for Alpha Aurigae is:

RA: 05h 16m 40s, dec: +45º 59' 46"

And for JNOW:

RA: 05h 18m 17s, dec: +46º 01' 17"

So, ASIAIR is (still) certainly much closer to JNOW than it is to J2000.

Chen

Bonzer2u

w7ay

Hi Chen,
As we speak today, do the Telescopius.com object coordinates work properly with the current 2.1.1(10.74) IOS asiair release?
Thanks,
Mike

w7ay

Bonzer2u Telescopius.com object coordinates work properly with the current 2.1.1(10.74) IOS asiair release?

I have no idea, Mike. I do not use Telescopius. But if your question pertains to JNOW vs J2000.0, I am pretty sure the ASIAIR is still using JNOW.

Databases should always refer to some common epoch, like 2000.0. Otherwise they are useless (like the database in ASIAIR) if you want to go to the same object a couple of years from now. Nutation eats you alive. Perhaps ZWO's folks have never played with spinning tops when they were youngsters, and don't know of the need for common epochs that get converted only when you use them, to JNOW.

Chen

viperduude

I recently tried imaging a target whose coordinates were given in the J2000 epoch. I used the Telescopius converter to get these coordinates in JNOW. AA+ reported the target was below the horizon when I know it was at 35° altitude. It probably was the calculator's fault. But even if I'd gotten a good conversion, it is a royal pain to switch between apps to copy coordinates from one to another. Could you PLEASE implement a user-friendly way to allow us to enter J2000 coordinates in Preview and in Plans and signal to AA+ that the coordinates are in J2000 and need to be converted to JNOW????

w7ay

viperduude It probably was the calculator's fault.

Check the before (J2000) and after (JNOW) numbers. There should be no more that a few minutes of RA, and likewise a few arc minutes of declination difference. Just enough to move a star off a little from the center of the sensor. This will show whether ASIAIR is the culprit, or the converter is the culprit.

That being said, the current ASIAIR has a terrible bug after plate solving. ASIAIR often fails "sync and GOTO" after a plate solve -- it complains about the target being below the horizon even when the target is at the near the Zenith. Since ASIAIR does not report LST anywhere, it is hard to tell where the error is. A "sync" and then manually GOTO works fine (i.e., the mount can move to the target -- it is ASIAIR that is FUBAR).

Chen

rdenbo

How do I save the current coordinates?

viperduude

rdenbo Create a custom catalog by hitting the "+" icon in the catalogs page.

igblaar

I completely agree with the points raised above. I'd like to add that the real problem is not only the default use of JNOW, but also the lack of consistency across ASIAIR’s different modules:

Preview mode and Plan mode use JNOW coordinates.
Plate solving, on the other hand, returns J2000 coordinates.
There's no clear indication or user control over the epoch being used at any point.

This inconsistency makes it easy to accidentally misframe a target, especially when switching between tools like Telescopius, SkySafari, or when reusing old plans. It also breaks expected behavior — if you plate solve a frame and expect to re-center on it later using the same coordinates, it may not land correctly.

My suggestion:

Unify everything to J2000, which is the standard in astronomy.
Alternatively, offer a clear toggle or setting for the user to choose the coordinate epoch.

At the very least, make it explicitly visible which epoch is being used at each point in the interface.

Thank you to the ZWO team for considering this — it’s a detail, but one that would significantly improve interoperability and long-term usability.