Let’s talk space. Shall we?

maggiemole wrote:

The London night sky is too polluted with ground lighting to see much with a telescope. I'd love to be able to take pictures like these here.

Hogwash! Most of these images were taken or could be taken in my RED/WHITE Zone(Very Light Polluted) backyard. Once you get to a certain amount of light pollution adding more doesn’t really make it that much worse.

The key is that you have to use filters to take out the light pollution. The spectrum of light that most lights use is known and in the past that spectrum of light was not that broad. You can use filters to simply take out that spectrum.

If you look at the two images of M27 below you will see that the core turns from Blue to Green when you use a Strong Light Pollution filter. This filter alone allows me to take 2 full stops more exposure in my backyard than without it.

Now adding the filters means you need to track and guide better as well for the longer durations. That isn’t quite as simple. Good mounts cost money. Lots of money. I prefer to use a lower end mount and just get a better camera and use a higher ISO.

The images below are composed of ISO 400 subs. They are really clean. If I go to ISO 1600 or higher I will get much better tracking but I also will get much more noise. The key is to reduce that noise by stacking the images together. Noise is chaotic. If you take several images of the exact same thing with the exact same settings then the only difference should be the noise. You can remove that noise simply by comparing the images programmatically and then removing the differences.

I have always said that I would do a tutorial on how to produce images like this. However, I never felt like I knew enough to do it justice. That and most established AP photographers won’t listen to any argument that doesn’t have the word “Canon” in it. That is different now. I finally am at the point where I feel like I can handle any situation that arises and the old school AP guys have finally started to see what m4/3s can do.

I take all of these pictures with about $1500 of equipment including the mount, scope, and camera. The videos require the GH4 for 4K but even the 1080p of the GH3 and GH2 were fantastic. It can be done and it can be done on a budget. It just takes a lot of work and tweaking.

M27 1 Minute Subs ISO 400 without any Filters

M27 8 Minute Subs ISO 400 with a Strong Light Pollution Filter