Light Pollution Filters

[stephec]

I live between Bolton and Manchester in what Clear Outside calls a bortle 6 area, built up and lots of street lighting. 

 

I was thinking of getting a filter so went on to FLO's website and searched for 'pollution filter' and now I'm more than a bit confused. 

 

A bit of advice then please, what do I go for in 1.25"?

[Cosmic Geoff]

It depends what you want it for.  Much street lighting is now white LED, which emits a continuous spectrum.  Light pollution filters for visual use formerly relied on excluding the narrow bands emitted by sodium or mercury lighting.  So for visual use, no "Light pollution filter" will be much use nowadays for looking at white objects like galaxies.

On the other hand, if you want to observe gaseous nebulae, which emit light in narrow spectral lines, a narrowband pass filter, e.g. OIII, will increase contrast.

And if you want to image nebulae, narrow band or "dual band" filters can work very well.

[Louis D]

To build on what has been said above, I would recommend not going with a wider passband than that found in a UHC type filter.  Think of them as a more selective light pollution filter for use on nebula.

The only way you're going to see galaxies is to seek out a truly dark sky site to observe from.

[Don Pensack]

https://www.eyepiecesetc.com/Choosing_a_Nebula_Filter_p/nebula-filters-explained.htm

[bosun21]

A UHC filter like the Astronomik is decent on emission nebulae and planetary nebulae. Galaxies require darker skies apart from the likes of M31, M81 and M82. However don’t expect to see any details in bortle 6 skies.

 

[PeterC65]

Just chipping in to mention that I have an Astronomik 1.25" UHC filter up for sale at the moment (here).

 

[Don Pensack]

5 hours ago, PeterC65 said:

Just chipping in to mention that I have an Astronomik 1.25" UHC filter up for sale at the moment (here).

 

What generation?  Pre-2017, or after, when the bandwidth was made narrower?

[PeterC65]

4 hours ago, Don Pensack said:

What generation?  Pre-2017, or after, when the bandwidth was made narrower?

It's the 2022 vintage. I use one regularly for visual, but I'm finding the Optolong L-eNhance better for EAA as it cuts IR.

 

[estwing]

The best light pollution filter is still a tank of petrol...

[stephec]

Thanks everyone, plenty for me to think about now.