Gaps in the NGC Catalogue for the GoTO Catalogue Target/Co-ordinates tool

[Acrux]

I have become a fan of the GoTo Catalogue Target/Co-ordinates tool. It is simple, quick, accurate and reliable.

However, there seem to be many gaps in the NGC Catalogue within this tool. For example, the following are some of the DSO’s with NGC designations that I have not been able to find in the catalogue - NGC: 6520, 6723, 6726, 6727, 1841, 6320, 3918. I could list many more that I have searched for and have drawn a blank during EAA observing sessions.

It is such a simple search function, so, I am sure I am not missing something. Or, am I? Can these gaps be filled in some way?

I am currently searching elsewhere for the coordinates and then pasting them into the tool for these missing NGC entries. It would be nice if the catalogue was complete.

As an aside, I found NGC 104 (Tuc 47) okay but noticed that it’s entry is NGC 104.47! Searching “104” does find the entry so the oddity is not too much of a problem.

[ChrisR Oz]

Also found NGC 7424 to be missing recently and IC objects.
Cheers, Chris.

[admin]

Hi folks,

I actually use a database called 'OpenNGC' as the source of data for the NGC/IC catalog, so if those targets are missing then it sounds like the database was incomplete (at least when I took a copy). OpenNGC (https://github.com/mattiaverga/OpenNGC) is useful because the licensing around the data allows re-use in commercial applications.

It looks like there have been some updates to that data source since I took a copy, so I will see if that brings in any of the missing targets, if not then I may have to try to find an alternative source of data for them.

Unfortunately this isn't a quick 'change 3 lines of code and put out a new version later this afternoon' fix, so it will take a while to get this sorted.

cheers,

Robin

[Acrux]

Thanks, Robyn.

I can be patient as we do have a work around using the GoTo Coordinates option. I have found CDC the easiest work around as it has an easily accessed “copy coordinates” option for a target.

Steve.

[carlomuccini]

Anoter "Best of" is NSOG Deep Sky and Double Star and Asterism Database

Saguaro Astronomy Club Database version 8.1 https://www.saguaroastro.org/sac-downloads/

Carlo

[admin]

Hi folks,

just came back to look at this issue and on checking, all of the above listed NGC targets are already in the SharpCap catalogs.

I suspect that maybe you had one or more of the filters (altitude, brightness, time to meridian) switched on when searching, which will exclude any search results that don't match the filters.

If you use the search box in the full catalog and there are search matches that are being hidden due to the filters or because some of the categories are unticked, you will see text below the search box along the lines of '5 targets match but are excluded by filters/object types'.

Anyway, all is not wasted, since I have found that the new updates to the OpenNGC database include lots more magnitudes for objects, so I will have a go at merging that data into the current catalogs.

cheers,

Robin

[Acrux]

Thank you, Robin.

I had completely missed the point that the first search option was only searching the Messier and Caldwell catalogues.

I can find all of the objects I listed originally in the full catalogue.

Steve.

[admin]

Hi Steve,

actually, that's an interesting bit of feedback - should I make the full catalog available to the first search tool? I wonder if it would be workable or if it would be too confusing?

cheers,

Robin

[Acrux]

Hi Robin,

The layout of the search screen actually misled me in the very first instance. It was not obvious to me at the time that a search of 'the catalogue' was accessing a limited list. In fact, typing in 'N' (as the start of NGC) or the first digit (for an NGC target) in the search box immediately brings up a list of objects with NGC designations even before one has completed typing in the full designation for the target. This, together with the fact that my early searches were successful (they obviously had a Caldwell reference), led me to the wrong conclusion that all NGC designations were available at this search point.

So, it would not have been confusing to me in the first instance if the first search option was in fact searching the entire catalogue. To me, the 'Full Catalogue' option looks more like an 'advanced search option'

I hope this makes sense.

Steve.

[kaymann]

Hi Robin,

The layout of the search screen actually misled me in the very first instance. It was not obvious to me at the time that a search of 'the catalogue' was accessing a limited list. In fact, typing in 'N' (as the start of NGC) or the first digit (for an NGC target) in the search box immediately brings up a list of objects with NGC designations even before one has completed typing in the full designation for the target. This, together with the fact that my early searches were successful (they obviously had a Caldwell reference), led me to the wrong conclusion that all NGC designations were available at this search point.

So, it would not have been confusing to me in the first instance if the first search option was in fact searching the entire catalogue. To me, the 'Full Catalogue' option looks more like an 'advanced search option'

I hope this makes sense.

Steve.

Steve that was my exact impression as well advanced vs. full search