NGC 1007 is invisible (1.4.0pre9)

[ajtribick]

While going on a fairly random tour of the galaxies, I found that NGC 1007 is invisible from most orientations.

Is it located near some distance threshold?

Celestia 1.4.0pre9 (PC)

[t00fri]

While going on a fairly random tour of the galaxies, I found that NGC 1007 is invisible from most orientations.

Is it located near some distance threshold?

Celestia 1.4.0pre9 (PC)

It's only invisible, since the default "faintestMag" parameter is set too low. That's exactly the same with stars: if you set the faintestMag too low you won't see them displayed.

Hence just increase faintestMag with ']' and you will see NGC 1007. Note that this galaxy is 16.8 (!) mag dim...

Bye Fridger

[ajtribick]

Hmmm... must be some kind of luminosity clipping then - I can only get this galaxy to display by using AutoMag at the highest level and a high zoom factor, but then rotating around it the galaxy disappears except when looking at it edge-on.

[t00fri]

Hmmm... must be some kind of luminosity clipping then - I can only get this galaxy to display by using AutoMag at the highest level and a high zoom factor, but then rotating around it the galaxy disappears except when looking at it edge-on.

OK, I can reproduce the effect. With automag=off I need to set faintestMag=14 (using the ']' key) to see NGC 1007 nicely from a distance. But when I approach it (using 'G'), then it indeed gets clipped and becomes invisible. So I'll look into that. It is surely a trivial issue, probably due to making the nebulae display less bright after FT1.2.

Bye Fridger

[t00fri]

Hi all,

OK I located the reason for the sudden extinction of NGC 1007. The crucial octree size parameter DSO_OCTREE_ROOT_SIZE
was just a little too small and thus the furthest galaxies in my deepsky.dsc catalog will be extinguished upon approaching them.

I will commit a fix to CVS and let you know when people may download the (corrected) code for recompiling it.

Bye Fridger