97 replies to this topic

[Starman1]

2022 Nebula Filters Buyer's Guide

Prices and model availability is updated.

Let me know of omissions.

Thanks.

Don

Attached Files

•  2022 Nebula Filter Buyers Guide.xlsx   14.62KB   3473 downloads

[Bean614]

Thanks Don!

[Look at the sky 101]

Thank you very much. 

Edited by Look at the sky 101, 22 March 2022 - 06:07 PM.

[Oiburg]

Thanks Don

 

Could you give me your feed back for this one?

 

https://www.robtics....bw-2458395.html

 

I have a chance to get one used (half price). I think it should work nicely in my 12" dob, right?

 

Only for visual

Edited by Oiburg, 05 April 2022 - 08:49 AM.

[Starman1]

Thanks Don

 

Could you give me your feed back for this one?

 

https://www.robtics....bw-2458395.html

 

I have a chance to get one used (half price). I think it should work nicely in my 12" dob, right?

 

Only for visual

There are two O-III lines of importance to visual observers.  One is at 495.9nm, the other at 500.7nm.

The 500.7nm line has about 3x the energy of the 495.9nm line, so a ratio of 25% to 75%.

 

Photographic O-III filters narrow the bandwidth to pick up only the 500.7nm line.

Imagers can just expose longer to get the image brightness they want.

Visual observers, though, need all the light we can get.  We don't want to lose 25% of the nebula light.

Visual O-III filters should include both of the important O-III lines in transmission.

 

The Baader filter is too narrow to pick up both O-III lines.  You need at least 11nm bandwidth and preferably 12nm to be sure you pick up both lines at a high enough transmission level

that contrast is enhanced without seriously darkening the nebula.

 

In my Nebula Filters Buyers Guide, I specify the single line O-III filters.  I recommend these for imaging, and the Baader O-III is a good example.

 

But for visual use, you will find it dark, and it will dim the nebulae you inspect.

If you are looking for a good O-III filter for visual use, I'd look at TeleVue (BandMate II) O-III, Astronomik O-III Visual, Lumicon (gen.3) O-III, 

[Oiburg]

As usual speechless with your knowledges and pedagogy

 

Thank you so much Don, I'll check these options you've suggested me instead of this 8nm excesively narrow

[tmichaelbanks]

Hi Don, I observe in Lincoln, RI, a suburban, white-to-red transition zone with a goodly amount of light pollution most nights, a little better directly overhead.

 

I'm interested in nebula viewing and understand that the Televue BandMate Type II filter would be best for this application.

 

However, will the TV BMII be an effective filter in this LP environment?  My previous experience with LP filters was far less satisfactory than I anticipated.

 

Thanks in advance for any guidance you can provide.

 

Mike Banks

Lincoln, RI

[Starman1]

Hi Don, I observe in Lincoln, RI, a suburban, white-to-red transition zone with a goodly amount of light pollution most nights, a little better directly overhead.

I'm interested in nebula viewing and understand that the Televue BandMate Type II filter would be best for this application.

However, will the TV BMII be an effective filter in this LP environment? My previous experience with LP filters was far less satisfactory than I anticipated.

Thanks in advance for any guidance you can provide.

Mike Banks
Lincoln, RI

I live in Los Angeles, the home of light pollution, and nebula filters do help here.
In this white zone, nebulae appear about the same with a filter as they do without a filter at my dark site. Of course they appear a lot better with a filter at a dark site.

One of the primary problems in the city is dark adapting. Nebula filters require you to be dark adapted, i.e. 30 to 45 minutes outside, away from all lights. If you are using a filter before you are dark adapted, your results may be poor.

And there are quite a large number of poor quality filters out there, which doesn't help.

A few of the good quality narrowband nebula filters:
TeleVue Bandmate II Nebustar
Lumicon UHC Gen.3
DGM NPB
Astronomik UHC visual
Orion Ultrablock (these have threading issues in most eyepieces)

Edited by Starman1, 09 June 2022 - 01:33 PM.

[tmichaelbanks]

Thank you for the quick reply Don, I appreciate it.

 

After rummaging around in storage, I unearthed an Orion Ultrablock.  I had bought it in 2018 to see if it would help viewing using my 8-inch Dob.  Didn't seem to make much difference but I've had more observing experience since then so I'll give it another try looking for the veil in Cygnus.

 

Just wondering, how much better do you think the TeleVue BandMate II Nebustar filter is versus the Ultrablock?  Worth the difference in price?

 

Thanks again,

Mike

[Starman1]

Mike,

The Ultrablock and Nebustar are similar--no red wavelengths transmitted.

The filter threading on the Orion filter is non-standard, and the bandwidth and transmission more variable than the Nebustar,

but both, when made to standard, work similarly.

My own personal opinion, having used both at the same time when testing 55 different filters a couple years ago, was that the glass in the Nebustar appeared to be better optical glass.

 

When it comes to the Veil, the intensity of the H-ß spectral line is weak, and the narrower TeleVue O-III filter will provide a higher level of contrast.

The O-III filter has a bit less than half the bandwidth, so you gain appreciable contrast.

 

Just so you know, the best objects for a narrowband filter like the Nebustar are the H-II region, star-forming, areas like M42, M8, M20, M17, M16

The best objects for an O-III filter are most planetary nebulae (Helix, Dumbbell), supernova remnants (Veil), and Wolf-Rayet excitation nebulae (Crescent, Thor's Helmet).

 

The Nebustar/UHC varieties pass the O-III lines, so they work quite well on the O-III targets, but maximum contrast is with an O-III filter.

I would say that if you own just one filter, the Nebustar/UHC/Ultrablock/NPB filter would be it.  But if you can afford to have two filters, add a good O-III as well.

[tmichaelbanks]

Thanks again for the very specific info and guidance Don.

 

I'm going to try out the Ultrablock on the southern nebula targets (M8, 20, 17, 16).  They are just coming into view now and I've got a decent look from my back deck.  I have the Q70 38mm and 26mm for some wide angle views and (hopefully) the Ultrablock's threading will work with those.

 

If those work decently, I'll order the TV O-III.

 

If I could pick your brain further, I'm trying to decide on a 3-4mm eyepiece for my AF72EDII to get 108x - 144x.  I've been using Delos eyepieces for the long eye relief (I wear thick eyeglasses), but would like something a little less expensive for those rare good-seeing nights here in Southern New England.

 

Do you have an opinion on the TV 3mm DeLite versus the Pentax XW 3.5mm for higher-mag looks at planets and the moon?  Both have 20mm eye relief.  The TV has the adjustable barrel, but the Pentax AFOV is 70 deg. versus 62 deg. for the TV.  Much difference quality-wise in the views?

[Starman1]

Thanks again for the very specific info and guidance Don.

 

I'm going to try out the Ultrablock on the southern nebula targets (M8, 20, 17, 16).  They are just coming into view now and I've got a decent look from my back deck.  I have the Q70 38mm and 26mm for some wide angle views and (hopefully) the Ultrablock's threading will work with those.

 

If those work decently, I'll order the TV O-III.

 

If I could pick your brain further, I'm trying to decide on a 3-4mm eyepiece for my AF72EDII to get 108x - 144x.  I've been using Delos eyepieces for the long eye relief (I wear thick eyeglasses), but would like something a little less expensive for those rare good-seeing nights here in Southern New England.

 

Do you have an opinion on the TV 3mm DeLite versus the Pentax XW 3.5mm for higher-mag looks at planets and the moon?  Both have 20mm eye relief.  The TV has the adjustable barrel, but the Pentax AFOV is 70 deg. versus 62 deg. for the TV.  Much difference quality-wise in the views?

Be sure to be fully dark adapted--filters don't work well, otherwise.

Also, keep magnifications low, like 10x/inch of aperture and lower.  With magnification increase, the effects of the filters dwindle away.

 

The Delites have an iris diaphragm built into the eyecup that helps block peripheral light reflection.  I think you'd use the Delite a lot.  It's super-sharp to the field stop.

It was 60x/inch in my 4" apo, so I didn't use it that much.  A 3.7mm Ethos gets used more at 45x lower magnification.

So the possibility is the roughly 16% more magnification from the 3mm might be better in your AT72 for double stars and lunar/planetary: 143x versus 123x.

On the other hand, the 3.5mm would be a lot brighter image and less likely to hit the seeing ceiling, so you might use 123x a lot more, just like I use the 3.7mm a lot in my apo but rarely used the 3mm.

[JimP]

Don,

I purchased a Collins I three IP’s many many years ago and am starting to use it again on my SVX 102D and May also try using with my TEC 140 or AP 155 telescopes. To say I am confused would be putting it mildly. Do you have recommendations for a few/several filters to use with the Collins I3 eyepiece.  Specifics would be greatly appreciated.

 

 Jim Phillips 

[Starman1]

Jim,

We've had some PM communication.  Perhaps others reading your post might have their suggestions?

[Tubuskahusk]

This will be my first filter purchase and I am not sure what to get. I want one that I can get the most millage out of and then add more later. I am quite sure that I want a 2 inch Tele vue. I was thinking maybe the Bandmate type 2 0lll. But I am not sure. Or would the Nebuster from Tele vue be a better choice or something totally different?Any advice would be greatly appreciated. I definitely want a high quality filter.

Edited by Tubuskahusk, 26 October 2022 - 03:24 PM.

[Starman1]

This will be my first filter purchase and I am not sure what to get. I want one that I can get the most millage out of and then add more later. I am quite sure that I want a 2 inch Tele vue. I was thinking maybe the Bandmate type 2 0lll. But I am not sure. Or would the Nebuster from Tele vue be a better choice or something totally different? Any advice would be greatly appreciated. I definitely want a high quality filter.

The emission nebula we can see emit light in 3 prominent spectral lines we can see at night:

H-ß at 486.1nm

O-III at 495.9nm

O-III at 500.7nm.

Many nebulae emit light at all 3 lines

Some only emit light at H-ß, and some at only O-III.

If you don't want to research the spectrum of each nebulae, here is a basic guide:

Large H-III region nebulae like M8, M20, M17, M16, M42--all 3 lines

Most Planetary nebulae--O-III lines

Most Wolf-Rayet excitation nebulae like NGC2359, NGC6888---O-III lines

Supernova remnants--O-III (the Veil) or all 3 (Crab)

Large ultra faint H nebulae normally seen in photos only--H-ß line.

 

What filter does them all?  The narrowband filter that passes all 3 lines.

Examples:

TeleVue BandMate II Nebustar

DGM NPB

Astronomik UHC Visual

Lumicon UHC

Orion Ultrablock.

 

Later on, if you are looking for another, second, filter to give a trace more contrast on selected objects, try an O-III filter.

Examples:

Astronomik O-III

Lumicon O-III

TeleVue BandMate II O-III

 

Filters are used at low power (under 10x/inch of aperture usually), which means if you use high powers to look at planetary nebulae, you'd do so without a filter.

The higher the power, the less effective the filter is.

[davidgmd]

What filter does them all?  The narrowband filter that passes all 3 lines.

Examples:

TeleVue BandMate II Nebustar

DGM NPB

Astronomik UHC Visual

Lumicon UHC

Orion Ultrablock.

  
As usual, Don nails it with a pithy explanation.
 
I bought one of the above (the Astronomik UHC visual) as well as an OIII and H-β. The UHC is by far the most versatile. The O-III occasionally shows some different details but not dramatic in my Bortle 5 skies to my relatively novice eye. And the H-β needs much darker skies to be of value.

[Look at the sky 101]

Good evening Don,

I am wondering if a nebustar filter from televue could be useful for me.

I would like to use it with my Tele Vue 85mm.

My sky is between 7 and 8 on the scale. 

Is it possible and useful ?

Thank you Don.

[Starman1]

Good evening Don,

I am wondering if a nebustar filter from televue could be useful for me.

I would like to use it with my Tele Vue 85mm.

My sky is between 7 and 8 on the scale. 

Is it possible and useful ?

Thank you Don.

I think I answered that in post 16, but to be clearer, yes, it would.

Don't expect miracles, though.  Nebula filters don't make the nebula brighter, just suppress some of the extraneous light.

Edited by Starman1, 27 October 2022 - 12:57 AM.

[Tubuskahusk]

Thanks to everyone for the good input. I do appreciate it. So todayI took the big plunge  and I ordered the Tele vue 2inch Bandmate Nebustar Filter Type 2 from B&H. Should be here this coming Tuesday. I won't get to try it out any next week due to lots of rain and clouds forecast for the week. So that is typical. Anytime you order any type of astro gear the weather clouds up and rains. I should order more stuff in the summer. Either way it will be a win win situation.

Edited by Tubuskahusk, 28 October 2022 - 06:48 PM.

[NYJohn S]

Hi Don, Thanks for posting the guide!

 

Is the Arcturus H-Beta the deal it appears to be or is there something about it like the optical quality that's not at good as the others. I see it has the same 12nm bandwidth as the Televue and Astronomik for $100 less in the 2" version. It's actually on sale locally for $99.

 

I was thinking about picking one up for my next dark site trip.

 

Thanks

John

[Starman1]

If you read the text, the implication is the Arcturus H-ß filter is an Orion H-ß filter.

It's unclear whether it's a 2", since the picture and text are of the 1.25".  I would call.

Let's look at the Orion H-ß filter.

I see 3 of them tested in the Searchlight lists, but one had too low a transmission, so perhaps there is a variability in quality?

The Orion 2" is now $129.99

This was mine, when tested:

Attached Thumbnails

• 

Edited by Starman1, 05 November 2022 - 02:10 PM.

[NYJohn S]

Ah, so it's a rebranded Orion, I missed that. I checked and it is a 2" filter. Now the only concern is will I get one in the correct bandwidth if they vary that much. I guess that's why the others cost more. 

 

Thank you Don!

[ASTROMILK]

I live in Los Angeles, the home of light pollution, and nebula filters do help here.
In this white zone, nebulae appear about the same with a filter as they do without a filter at my dark site. Of course they appear a lot better with a filter at a dark site.

One of the primary problems in the city is dark adapting. Nebula filters require you to be dark adapted, i.e. 30 to 45 minutes outside, away from all lights. If you are using a filter before you are dark adapted, your results may be poor.

And there are quite a large number of poor quality filters out there, which doesn't help.

A few of the good quality narrowband nebula filters:
TeleVue Bandmate II Nebustar
Lumicon UHC Gen.3
DGM NPB
Astronomik UHC visual
Orion Ultrablock (these have threading issues in most eyepieces)

Hey Don, I’m not sure if the Baader UHC-s is a new product since this post but do you recommend this filter for observing with 30mm uff through 10” f/5 In a level 5 bortle or would I need to go to much darker skies to get my moneys worth from a nebulae filter?

Thanks!!! -Milk

[Starman1]

Hey Don, I’m not sure if the Baader UHC-s is a new product since this post but do you recommend this filter for observing with 30mm uff through 10” f/5 In a level 5 bortle or would I need to go to much darker skies to get my moneys worth from a nebulae filter?

Thanks!!! -Milk

The Baader UHC-S is a very good broadband filter.  It's been around for many years. My sample has a 62nm bandwidth in the blue-green and an unlimited bandwidth in the red.

I preferred it to the Lumicon Deep Sky and the Orion Sky Glow.

As such, it will enhance contrast only a tiny bit, and really won't come into its own until the skies are quite dark (say, 21.2mpsas or darker), more like Bortle 3-4.

There, a small increase in contrast might be noticeable.

 

Even there, the UHC-S only has a small effect, and contrast is only slightly enhanced.

Where I find the filter handy is on objects like M20, where narrowband filters simply kill the reflection nebulosity and enhance the emission part.

The UHC-S doesn't kill the reflection part, but enhances the emission part significantly less.

 

In a city, they often render the effects of light pollution WORSE, by creating a lot of light scatter internally in the filter.

 

There are some valid reasons to have a good broadband filter, but it would be AFTER you have a good narrowband, O-III, and H-ß filter.

Any UHC filter labeled UHC-S, UHC-E, UHC/LPR or UHC/CLS is not really a narrowband filter.

From the standpoint of contrast enhancement, they should just be called "contrast filters", and leave off "ultra high".

 

A true "nebula filter", like the ones I mentioned in the quoted post, IS useful in a city.  But the broadband?  Not so much.