Annotation script

[pfile]

actually along these lines, if i go to the hyperleda website and ask for a portion of the sky i am interested in, i see many more galaxies in the website output than what shows up after annotation. is the hyperleda catalog that's bundled with the script somehow reduced in size?

[Andres.Pozo]

actually along these lines, if i go to the hyperleda website and ask for a portion of the sky i am interested in, i see many more galaxies in the website output than what shows up after annotation. is the hyperleda catalog that's bundled with the script somehow reduced in size?

The script uses the catalog VII/237/pgc directly from Vizier. The script does not bundle data apart from the NGC/IC catalog.
I have done several tests and I can not find missing galaxies. I would need an example of this effect so I can reproduce it and then fix it.

[pfile]

i happened to solve an image of a contact on flickr. i don't have permission to redistribute it, but here's a thumbnail of the solved image together with a thumbnail of what i get from the hyperleda server.

this is the area of M51. the two FOVs are not the same, but assuming the green circles in the hyperleda output are galaxies in their database, you can see that many of the galaxies are not annotated in the pixinsight image.

[Andres.Pozo]

I don't know where do you have got that image. The annotation script shows all the objects in the catalog VII/237/pgc.
The attached image compares the result of annotation script with the Aladin  viewer that uses the same catalog as me. The fields are slightly different but it can be seen that both images have annotated the same galaxies in the field that both have in common.

[pfile]

well maybe hyperleda is different than the PGC catalog then. i am away from my main computer but i can send you the URL that i used to generate that image. it's from the hyperleda website, though.

assuming this is just a matter of using a different catalog, what format should a catalog be in in order for the annotate script to use it? does it have to be online somewhere or can it be stored locally?  a full catalog of galaxies is probably huge.

[Andres.Pozo]

well maybe hyperleda is different than the PGC catalog then. i am away from my main computer but i can send you the URL that i used to generate that image. it's from the hyperleda website, though.

assuming this is just a matter of using a different catalog, what format should a catalog be in in order for the annotate script to use it? does it have to be online somewhere or can it be stored locally?  a full catalog of galaxies is probably huge.

The server of Hyperleda (http://leda.univ-lyon1.fr/) has more objects than are available in the catalog VII/237/pgc of VizieR. In the catalog of Vizier there are only the galaxies of the PGC catalog while in the server of Hyperleda there is a mix of stars and galaxies from different sources.

Since the server of Hyperleda is not easily integrated in the script I will add a couple of additional catalogs from Vizier:

• SDSS R8 (II/306/sdss8)
  
• GSC2.3 (I/305)
  

In both catalogs, the user will be able to filter the catalog by magnitude and object class (star/galaxy).

[pfile]

yes, you are right, i thought everything in the hyperleda catalog was PGC but there are multiple designation types in there. i could not figure out how to get the hyperleda catalog, so thanks for adding those other sources.

[oldwexi]

Since the server of Hyperleda is not easily integrated in the script I will add a couple of additional catalogs from Vizier:

• SDSS R8 (II/306/sdss8)
  
• GSC2.3 (I/305)
  

In both catalogs, the user will be able to filter the catalog by magnitude and object class (star/galaxy).

Thanks Andres for your work to make the GSC2.3 catalogue accessible with Class and Magnitude selection.
This will be a great progress for annotation of weak galaxies.

Aloha
Gerald

[EelkoGielis]

Hi,

I try to solve the next image:
http://www.flickr.com/photos/14721988@N02/6976343764/sizes/k/in/photostream/
but I don't seem to get it solved.

Settings:
RA: 13 29 52.598
Dec: 47 11 42.93
Epoch: 2000 1 1
Focal distance :654.667
Resolution: 2.3 arcsec/pixel
Pixel size: 7.3
Limit magnitude: 12
Star sensitivity: 1.01
Show stars (does show the stars, not the noise)
Maximum iterations: 8
Update FITS keywords
Add WCS keywords

astrometry.net
Hello, this is the blind astrometry solver. Your results are:
(RA, Dec) center:(202.392357488, 47.205237112) degrees
(RA, Dec) center (H:M:S, D:M:S):(13:29:34.166, +47:12:18.854)
Orientation:86.69 deg E of N
Pixel scale:2.30 arcsec/pixel
Parity:Reverse ("Left-handed")
Field size :39.21 x 29.25 arcminutes

[Andres.Pozo]

Hi,

I try to solve the next image:
http://www.flickr.com/photos/14721988@N02/6976343764/sizes/k/in/photostream/
but I don't seem to get it solved.

Your starting parameters are wrong. It seems that you has sent to Astronometry.net a half size version of the image. The resolution of the image of the link is 1.15" instead 2.3".

Using the parameters of the attached screenshot, the result is:

Code: [Select]

Image Plate Solver script version 1.6
===============================================================================
Referentiation Matrix (Gnomonic projection = Matrix * Coords[x,y]):
        +0.000019408940     +0.000319144419     -0.263694215186
        -0.000319912238     +0.000019277221     +0.312870900766
        +0.000000000000     +0.000000000000     +1.000000000000
Resolution ........ 1.152 arcsec/pix
Rotation .......... -93.395 deg
Focal ............. 1306.60 mm
Pixel size ........ 7.30 um
Field of view ..... 39' 20.1" x 29' 20.9"
Image center ...... RA: 13 29 34.623  Dec: +47 12 13.19
Image bounds:
   top-left ....... RA: 13 28 00.918  Dec: +47 30 57.09
   top-right ...... RA: 13 28 16.019  Dec: +46 51 39.18
   bottom-left .... RA: 13 30 54.248  Dec: +47 32 43.79
   bottom-right ... RA: 13 31 07.229  Dec: +46 53 24.56
===============================================================================


[EelkoGielis]

I got it to work.

Now, how did you get the number for the resolution?

[Andres.Pozo]

I got it to work.

Now, how did you get the number for the resolution?

I guessed it but for you it should be easy. You should know the focal length of your tube and the pixel size of the camera.

[zvrastil]

Hello Andres,

today, I used your excellent script on the image of Whirlpool galaxy. I have the problem I did not experienced before - several duplicates between NGC and PGC catalogs, not removed even with "Removed Duplicated objects" checked (including M51). Is there a way to fix it?

thanks a lot, Zbynek

[Andres.Pozo]

Hello Andres,

today, I used your excellent script on the image of Whirlpool galaxy. I have the problem I did not experienced before - several duplicates between NGC and PGC catalogs, not removed even with "Removed Duplicated objects" checked (including M51). Is there a way to fix it?

What is the resolution of the image?

Andrés.

[troypiggo]

Hi Andres,

I think I found a bug, or at least an oddity.  I've noticed with my images that if I overlay Tycho stars, that in the corners the annotations don't quite line up with my image's stars.  I have just been putting that down to distortion in my optics and the field not being flat.

But tonight I was playing around with a star generated image.  I generated a star field, then solved the generated field, then annotated that image.  The annotations in the star generated image are slightly off the stars in that too.