Night filters

[thebeardedgroundsman]

Night time filters to cut down the effects of light pollution appear to be relatively new ( found one article suggesting the first generally available ones were marketed in 2018).

Has anyone had experience with them? How effective are they?

The ones from "quality" filter manufacturers seem to cost around £130 for 77mm filter threads or 100mm square. So they appear to be a substantial investment, so real life experiences would be great to hear about, before making a purchase.

[LiveShots]

Until now, I’d never heard of them. I wonder if there is a way to duplicate their function in post-processing 

[astrnmrtom]

I know this post is a few month's old now but I'll offer some info. Light pollution filters have been around for quite a while in the astronomy community - since the late 1970s(?) Most imaging was done through a telescope so they were sized for that purpose. It's only somewhat recently that there's been a big surge in widefield and telephoto astrophotography which is why you are seeing them for cameras now. I owns several type and have used them visually through a telescope for 30 years. I'm finding I rarely use them anymore because they are much less effective. I have not used them for astrophotography though.

 

As for effectiveness? They are getting less and less effective as the world switches to LED lighting. A lot of the light pollution used to be from mercury vapor or sodium lighting which emitted light at a handful of specific wavelengths. By making a filter that blocked those specific wavelengths but let other through, you could increase contrast by reducing skyglow. Unfortunately LEDs emit a much wider spectrum so are almost impossible to filter out because you end up blocking the light of the object you are imaging too.

 

This article should be helpful: https://www.bhphotovideo.com/explora/photography/hands-on-review/9-light-pollution-filters-tested-do-they-really-work

 

Now, a lot of light pollution is dealt with in post processing. If you want to dabble in astrophotography, I suggest joining a forum for that specific topic. https://www.cloudynights.com/forum/74-astrophotography-and-sketching/

Hope this helps. Tom

 

[thebeardedgroundsman]

Since asking the question, I have bought a Haida "clear night" filter and found a big reduction in the "Muddiness" of night time light. (I live in a high light pollution area.)

Edited July 27, 2021 by thebeardedgroundsman