I use Telescope Simulator and choose “JNow” for Coordinates Epoch in “Mosaic Settings” as I use ZWO ASIAir Plus. When I’m done with the FOV, I export it to a Target List. Then, when I go to the Target List and choose the target, it takes me back to Telescope Simulator but the FOV is slightly shifted. I believe the coordinates in JNow in Telescope Simulator is passed to the Target List but the Target List takes them as J2000.
Actually, this FOV shift does not happen when I choose “J2000” in Telescope Simulator and export it to the Target List.
Target List should remember if the coordinates are in JNow or J2000. Hopefully, it also shows “JNow” or “J2000” somewhere near “DEC” or “RA”.
For now, I have to re-export all targets to my Target Lists with “J2000” chosen.
Indeed, what you described is the current (bad) behavior, thanks for your report!
I’ll have to use J2000 under the hood always and only display Jnow where appropriate. This is part of a bigger refactor to display J2000/JNow across the site, not just the simulator. I’ll update this topic once this is fixed.
Thank you very much! Looking forward to the improvement. Just add a tip. It turned out that in the Plan mode of ASIAir Plus, there is “Import” feature which expects the coordinates in J2000. So, ASIAir Plus also mixes J2000 and JNow (the Preview mode expects JNow).
I just got caught up in this and I ended up refactoring many places to allow choosing between j2000 and jnow all around the app in version 241128, just released.
Besides the target lists themselves, you can also switch the epoch while editing the targets, but also in the telescope simulator, DSO pages, ephemeris tables, constellation pages, and plate solved pictures coordinates.
One detail is that old targets in lists which were created from the simulator could be in either j2000 or jnow, no way to tell so I couldn’t migrate them automatically.
