What Advice Do You Have for a Light Pollution Filter?

[rabbithutch]

My place (yard/garden) is very polluted by stray light from a shopping center about 400 yards away. I can view the Moon without problems (to belabor the obvious) but I have a great deal of difficulty trying to view planets and any DSO's. I can see Orion quite well on clear nights but cannot see the belt in the telrad to align for the nebula - much less see the nebula. I assume this is due to the LP.

What do I need to know to begin shopping for an LP filter? The scope is an older Orion 8" Newt on a Dobsonian mount. Any help including your advice and pointers to online articles would be most appreciated.

TIA

[Ben Ritchie]

The best solution is to pack up the 'scope and head out to the nearest dark sky you can find - if the light pollution is extreme (as it sounds like here, if you can't see Orion's belt) then there are limits to what a filter isn't going to achieve.

The best option I can think of is one of the UHC filters, which cut out almost everything to leave just the [O III] and H-beta lines seen in emission nebulae. These are quite effective in high light pollution, but only for relatively few emission-line objects (no good on galaxies or open/globular clusters). Otherwise it depends a bit on what type of lights they are - things like low-pressure sodium can be removed reasonably well, but incandescent lights much less so. But really there's no substitute for heading out to darker sky.