<p>I have uploaded a h alpha photo in SAO Image DS9, but want to locate a particular region for which I have the galactic coordinates. How to input the coordinates in DS9 to view the particular zone?</p>

CC BY-SA 4.0
2018-07-29T04:53:29.440Z
Does the image already have a World Coordinate System so that you see RA and Dec (alpha and delta) values as well as the pixel coordinates?
astrosnapper
CC BY-SA 4.0
2018-07-29T06:09:55.093Z
Put circular region down, and check its info. Edit the center of that circle to wherever you want. Will that work?
Kornpob Bhirombhakdi
CC BY-SA 4.0
2018-07-29T13:51:28.943Z
It works. Thanks. Just that the location does't look like a h alpha region, even if I change color and scale. I am looking for SH 2-27 (Sharpless ctalog) and according to http://galaxymap.org/cat/view/sharpless/27 its Galactic coordonates are: 6.28°, 23.59° . wathever I switch longitude (l) for latitude (b), It gives a zone without halpha appearence. It's frustating...
Rulx Narcisse
CC BY-SA 4.0
2018-07-29T21:50:59.990Z
Is the image that you are looking at taken in a filter that includes H-alpha (656nm) ? If not, then you won't see it. If you look at NGC1499 (CA Nebula) in AladinLite using PS1 (http://aladin.unistra.fr/AladinLite/?target=04%2003%2018.000%2B36%2025%2018.12&fov=5.00&survey=P%2FPanSTARRS%2FDR1%2Fcolor-z-zg-g) there is no sign of the nebula as the _g_ and _z_ data used are much bluer and redder of the Halpha line. Switch to the 'VTSS/Halpha' data, which uses a Halpha filter, and it's an huge signal. Also be sure the data covers a big enough field of view; many HII regions are very big on the sky.
astrosnapper
<ds9>
Galactic coordinates input in DS9
Rulx Narcisse
# Galactic coordinates input in DS9

(Asked by: username_0 on 2018-07-29)

I have uploaded a h alpha photo in SAO Image DS9, but want to locate a particular region for which I have the galactic coordinates. How to input the coordinates in DS9 to view the particular zone?

**Tags:** ds9

> **Comments:**
> **username_1**: Does the image already have a World Coordinate System so that you see RA and Dec (alpha and delta) values as well as the pixel coordinates?  
> **username_2**: Put circular region down, and check its info. Edit the center of that circle to wherever you want. Will that work?  
> **username_0**: It works. Thanks. Just that the location does't look like a h alpha region, even if I change color and scale. I am looking for SH 2-27 (Sharpless ctalog) and according to http://galaxymap.org/cat/view/sharpless/27 its Galactic coordonates are: 6.28°, 23.59° . wathever I switch longitude (l) for latitude (b), It gives a zone without halpha appearence. It's frustating...  
> **username_1**: Is the image that you are looking at taken in a filter that includes H-alpha (656nm) ? If not, then you won't see it. If you look at NGC1499 (CA Nebula) in AladinLite using PS1 (http://aladin.unistra.fr/AladinLite/?target=04%2003%2018.000%2B36%2025%2018.12&fov=5.00&survey=P%2FPanSTARRS%2FDR1%2Fcolor-z-zg-g) there is no sign of the nebula as the _g_ and _z_ data used are much bluer and redder of the Halpha line. Switch to the 'VTSS/Halpha' data, which uses a Halpha filter, and it's an huge signal. Also be sure the data covers a big enough field of view; many HII regions are very big on the sky.  

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## 0 answers

