Allow New Object Entry using ICRS (J2000) instead of JNow

dmcclain

Software then needs to precess + nutate + aberrate to JNow position. But current time is obviously available, and computing power is sufficient, so why make the user do all of this when the computer is the obvious workhorse?

Tech@ZWO

dmcclain Do you refer to ASIAIR or Seestar?

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.

igblaar

+1 to all the points above — and I’d also like to thank the ZWO team for the improvement introduced in ASIAIR 2.4 beta: it's now possible to enter coordinates in either J2000 or JNOW in Preview mode, which is a very welcome and much-needed step forward. Great work!

However, to truly complete the update and solve the internal consistency issue, it would be ideal if the Custom Object Catalog also allowed users to input coordinates in J2000. As of now, it seems to only accept JNOW coordinates, which creates the same old problem when planning sessions offline.

Why is this important?

When preparing sessions at home, especially for targets not in the default catalog (e.g., specific galaxies, IFN patches, custom framing), being able to input J2000 coordinates is essential for compatibility with tools like Aladin, SkySafari, Telescopius, or catalogs based on J2000 (which is still the standard in most astronomy tools and databases).

So, my request to the ZWO team:

Please allow Custom Catalog entries to be defined using J2000 coordinates, or at the very least let users specify the epoch (just like in Preview mode).

Also, a visible indicator of the epoch in each module would really help reduce confusion and avoid small but frustrating misalignments.

Thanks again for your ongoing work — ASIAIR is evolving beautifully, and this small detail would really improve both offline planning and interoperability with other platforms.