Nova.strometry.net solves my image but Telescopius doesn't?

Hi all,

Telescopius is solving most of my images but not all , i just tried one of those on nova.astrometry.net no problems solving ?
Also I use Astap when imaging to centre my object mostly and no problem plate solving there though thats straight off of camera.

Any ideas, suggestions,
Thanks
Cliff in Sydney

Hi Cliff,

There are many things going on, let me explain :slight_smile:

At the beginning Telescopius used the nova.astrometry.net API to request plate solving of all pictures, but some shortages on their service, some delays in many cases due to job queues, and their suggestion to run plate solving on our own servers to avoid waiting for their global queue, made me switch the implementation to have it running on our own server.

Plate solving works by using index files containing the position of stars. Nova uses a set of index files unavailable to the general public due to licensing issues (they are called the “200-series”), while our server uses a different set of index files which naturally gives different results. They offer 2 or 3 different sets of index files, I’ve tried them all and none of them solves difficult pictures the same way with the default settings.

I estimate over 95% of all deep sky pictures get correctly plate solved on Telescopius. When I noticed some images were being plate solved on Nova but not on Telescopius, I started trying different settings but none of them would work in 100% of the cases. I would really love to have the same index files because I’m not sure if the reason they are failing is because of the settings, the index files, or… hardware.

Index files are over 20GB. Some times the jobs time out before trying all index files due to memory constraints. I need to upgrade the system to have more memory but the current hosting is quite expensive. Given that about 95% of pictures get plate solved correctly, paying double or triple for the hosting service just to try to get the extra 5% solved didn’t make much sense, but I’m planning to migrate to another cheaper hosting to see if we can improve that number. Another idea is to try nova.astrometry.net only for failed pictures.

I’ll keep working on improving the success rate of plate solving. In the meantime, for pictures which don’t get plate solved blindly, you can add hints next to any one of the revisions (all revisions of a picture share the same hints) by clicking on the drafting compass icon:

image

Entering the coordinates or just the FOV usually helps a lot because it reduces the number of index files to search in. I hope this helps!

Thank you for the detailed response ,

I use Telescopius regularly the reason I am a patron , I understand now that the other site has access to non public indexes, I will try as you suggest and put hints in and see what happens.
There are not that many that don’t get solved usually widefields with lots of stars.

Not much more to add just keep up the good work Telescopius just gets better and better

Cliff

1 Like

Thank you for your kind words and support, Cliff! I really appreciate it :slight_smile:

There are a lot of cool features coming this year. Right now I’m working on our own Planetarium that will be integrated with several features of the site. Besides the fact that it will run on any browser without needing to download and install a planetarium software, it will also integrate with user pictures, the Telescope Simulator, and more. Hopefully I’ll release the first minimal version during February or possibly March.

Hi Sebastian,

Sounds great I might have to retire Stellarium :slight_smile:

Cheers
Cliff

It seems I’m late to the party but I have a suggestion to help plate-solving improve.

Why don't you use the nova.astrometry.net AFTER the internal/local solver fails?

Actually, Telescopius now uses nova.astrometry.net exclusively. The problem was that the process in charge to post images and fetch the plate solving result was frozen.

I need to investigate what went wrong so it doesn’t happen again, but it’s working fine now :slight_smile:

Now we’ll have to wait for a few hours until all pending images get solved as expected, sorry for the inconvenience!