Jump to content


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Filters for Galaxies

  • Please log in to reply
28 replies to this topic

#26 GGK


    Vostok 1

  • *****
  • Posts: 154
  • Joined: 04 Jan 2021
  • Loc: SouthWest Florida

Posted 15 April 2021 - 03:48 PM

For finding galaxies with my C8 SCT in Bortle 4 skies, the best filter I have is a dark hood covering my head and eyepiece. 


My normal lightweight hood that allows a small amount of ambient light through the fabric is fine for clusters and brighter objects. But for the small faint galaxies, I see a stepped improvement when changing to a very opaque hood that blocks all ambient light around my eyes.  I also wear an eyepatch over my other eye when using the dark hood.  I also have to remember to breath fully because if I start taking shallower breaths or hold my breath, I tend to have more difficulty seeing the faint objects.  



  • brentknight likes this

#27 vtornado



  • *****
  • Posts: 3,527
  • Joined: 22 Jan 2016
  • Loc: Northern Illinois

Posted 15 April 2021 - 10:12 PM

I live in Bortle 7 and can view Bode's galaxy with difficulty in an 100mm scope.


I have tried the orion sky-glow filter.  It does not enhance the view.

On paper I was thinking this filter would remove more light pollution, (sodium, mercury vapor)

than galaxy light (full spectrum).  But in reality I did not notice a difference.

#28 brentknight



  • *****
  • Posts: 2,890
  • Joined: 29 Dec 2014
  • Loc: Foley, Alabama

Posted 15 April 2021 - 11:03 PM

I think it really depends on what type of light is in your light pollution. To the south in my backyard, the lights are all yellow/orange. Filters seem to help somewhat with contrast. To the north in my front yard it's more full spectrum and I doubt I'd see much improvement (no improvement now since I can't afford the rainy cloud filter)...

#29 radiofm74


    Ranger 4

  • -----
  • Posts: 338
  • Joined: 17 Jan 2021
  • Loc: Milano (Italy)

Posted 19 April 2021 - 09:33 AM

Original post:

Posted 10 April 2021 - 11:34 PM
Hi all, I'm relatively new to astronomy and I have been using my new Orion Goto Star Seeker IV 150mm (f/5) reflector since this past Christmas to view the stars,  the Orion Nebula, Mars, the Moon and M31, M81, and M82 galaxies. I would like to see the galaxies better and wondering if there are any filters that could help. I was looking at the Lumicon UHC and the Orion Ultrablock filters, trying to keep the cost under $100. I'm using a 25mm plossl and the Orion 7.2-21 zoom. Thanks in advance for any suggestions.



Update: (April 14, 2021)

I went out last night in our light polluted skies in my backyard. With fairly accurate goto tracking I honed in on M-81 (Bode's Galaxy) and used some of the tips I received from the forum. I let my eyes adjust to the dark, I used little to no red light to set up, also tried to block all peripheral light, and used averted vision. I was surprised how well those simple techniques worked. I was able to see so much more of the galaxy and definitely saw the brighter center with the averted vision thing. I have a New York State Park Star Gazing Permit that allows me access to certain state parks on Long Island after they close at dusk. One spot I will soon get to is Hither Hills in Montauk. I have heard from many that it offers some of the darkest skies on the island for viewing. I have been to Montauk so many times and know how dark the skies are out there but I only brought my surfboard not my telescope (this time I'll bring both).

Congrats for your close encounter with Bode's Galaxy!


You got your answer re:filters but along the lines of what Tony Flanders and others did, I'd like to suggest two "light-pollution-resistant" galaxies for observation from your backyard: M94 (in CVn, the "Cat's Eye" or "Croc's Eye") and the awesome M104 ("Sombrero Galaxy").


Possible from the city for a newbie like us, but definitely harder: M51 (Whirlpool, wonderful), M63 (Sunflower), M64 (Black-eye), M65 and M66 (part of Leo's trio). 


To find them, and for your edification on Messier objects, may I suggest Tony's awesome guide: https://tonyflanders...essier-project/


These suggestions are the result of a one-month struggle with galaxy-hunting in urban settings (in the center of Milano, I'm around Bortle 7). I feel your pain and am a bit jealous of your getaway opportunity ;D But note this: while the Moon is up it will be much much harder to see dim objects like most galaxies are, even under a darker sky. I'll resume the quest from April 29, and meanwhile enjoy colorful doubles, the last visible bright clusters from Winter season, and the Moon itself.


Happy quest and clear skies!

  • brentknight likes this

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Recent Topics

Also tagged with one or more of these keywords: Beginner

Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics