Mis à jour : 28 déc. 2019
One of the most tiring aspects for us, or any amateur astronomer or astrophotographer is light pollution.
We have gone over it briefly during Episode 1 of Galactic Hunter and it deserves its own article to explain why it must be taken into consideration. Living in a city means there will be immense light pollution and that is true for Las Vegas as it is with other major cities.
Light pollution can be imagined as a bright blurry dome over the city that prevents starlight from shining through, however the farther we distance ourselves, the more it loses its effect.
Unlike the other enemy we face when going out onto the field which we cannot control, clouds or cloud cover, we can escape the light pollution from the city. We at Galactic Hunter do this by driving about 45 minutes out of the city and into the mountainous desert.
We have noted that Nelson’s Landing is our prime spot for stargazing because of its concrete level ground, decent weather, and the lack of people coming through the area to disturb us. It does not always mean that there are no people and occasionally we must share the space, but it is hardly an issue with most people we come across who tend to fish or swim in the area.
Another reason we choose Nelson as our distance from the light pollution. Also noted in Episode 1 of Galactic Hunter is the Bortle Scale. This scale measures the amount of light pollution distorting our view of the sky and has 9 levels, which Nelson’s Landing is a 3.5.
This is a great find considering the amount of time or trouble it takes to reach darker areas. The area is optimal for viewing the sky and the distance is fair given the proximity to a major city. Any level under 5 is, in our opinion, the best you can do if you do not live anywhere near dark zones.
The dark zones, or level 1 zones, are what you should look for but most are found too far within reasonable traveling distance or over the seas in true pitch black areas. Las Vegas is actually so bright that we still see the light pollution dome from Nelson’s Landing! We face the opposite direction often while we are taking images but it shows just how radiant the light pollution really is.
We wanted to know what M42, the famous Orion Nebula, would look like in a highly light polluted area (our apartment complex parking lot) compared to our usual desert spot, so we made a comparison. As you can see below, the difference is HUGE! It would be interesting to make the same comparison for a galaxy or a cluster.
Not long ago, we took a trip to Tonopah, NV so we could witness for the first time what a Bortle 1 zone would look like. After a 30 minute drive to complete darkness, we were amazed at how beautiful the sky was. We took a 3-minute exposure on the Helix Nebula (which we were supposed to image for four hours but our laptop decided to die and ruin our night....). Below you will see the difference between our usual spot (Bortle 3.5) and a Bortle 1 zone when it comes to astrophotography. Not only does the image reveal much more under truly dark skies, it also shows pretty much no noise at all (difficult to see on the image).
To end, light pollution is a tiring aspect for us, as well as newcomers to astrophotography and fellow astronomers. It is not controllable but it is escapable. It is always good for find a class 5 level or less for optimal sky viewing. It is good to note that there is a huge difference of quality when imaging in a light polluted area depending on if you are using a CCD camera or a DSLR camera.
When in doubt, simply drive as far away from the lights as possible.