8 replies to this topic

[Jairo]

Hi!

 

I have an 8-inch catadioptric, an AM5 mount, an off-axis guider, a Canon 60Da and an Atik 383L+ mono cooled camera. It should be good hardware for deep space photography. However, now I live in a Bortle 8 region.

 

I have two old filters: a Lumicon Deep Sky 1.25", and an Optolong UHC clip for the Canon. I was told they're not ideal anymore, since we're gradually switching to LED light instead of sodium and mercury light. And I see they're not helping much.

 

Right now, what is the best type and brands of filters for imaging galaxies (I guess it should be trickier than emission nebulas)?

Thanks in advance.

[rgk901]

this is the eyepiece forum folks in the imaging forums may have some ideas .. but I only know one way...darker skies...

although I see some with mono cameras due a bit better from light pollution on full spectrum objects like galaxies.

[rgk901]

oh... and lots and lots of integration time...

Edited by rgk901, 20 April 2025 - 12:21 PM.

[John Rose]

This really needs to be in the imaging forum. Some people have found some of the broadband filters some what helpful for galaxies in moderate light pollution. 

[Jairo]

Thank you! I will ask in the imaging forum.

However, this forum has "filters" in its description. I suggest the admins to change it then.

"Eyepieces

A place to discuss our favorite eyepieces and eyepiece accessories, barlows, FILTERS, etc."

[rgk901]

Thank you! I will ask in the imaging forum.

However, this forum has "filters" in its description. I suggest the admins to change it then.

"Eyepieces
A place to discuss our favorite eyepieces and eyepiece accessories, barlows, FILTERS, etc."

yes, visual uses filters too!

we use color filters to bring out plantery features... and we use narrowband UHC type/ OIII and H beta filters to help see nebula and such through regular glass eyepieces

we also have no filters for broad spectrum objects like galaxies

[John Rose]

Yes this forum is for the visual use of filters. Filters for imaging can be quite different. 

[Jay_Reynolds_Freeman]

Speaking of visual filters for galaxies: Galaxies tend to have warmish colors -- visual magnitude brighter than photographic. Airglow is bluish, and the sky scatters blue light preferentially over other colors -- that's why it is blue. Thus there is a case that a minus-blue or orange filter, something with a cutoff somewhere near the green, might improve the contrast of some galaxies when viewed visually in some conditions. That might be particularly true of galaxies which contain little dust, hence do not have a lot of new, bright, hot blue giants; such galaxies would have large numbers of old, bright, red giants.

 

I haven't tried this myself, it is just a thought.

 

 

Clear sky ...

[Starman1]

Spiral arms tend to be blue, so a blue filter could bring them out.

But really, the way to photograph galaxies is to travel to darker skies.

Galaxies and nebulae are dark sky objects.  Imaging star clusters is easier in brighter skies.