25 replies to this topic

[PIEJr]

So, I got curious reading some of the topics and decided to try a with/without LP filter on my ASI 2600MC Pro camera.

 

The difference the Antila Quad filter makes was interesting.

 

With the filter:

 

And without the filter:

 

Of course there are a lot of differences, like Moon brightness to consider. But someone advised to not use any filtering.

From my backyard, maybe the filter is a good idea. (It seems many prefer the brighter appearance. I like B&W up to loud and proud. (But not glaring)

I only have the one filter, or no filter options right now.

Another part of this experiment was to eliminate what appeared to be red stars (or hot red pixels) in other subjects.

 

My experiments are by doing, and not calculating. Try it and like it, or go back and be happy.

Another thing was chopping the exposure time in half, but the subs doubled.

35/300s, or 70/150s.

I believe I like the longer exposures (300s) over the shorter versions (150s). Brighter details in the longer subs.

 

I think I'll try 300s w/o the filter to get back to Apples to Apples comparison.

The moon will be it's typical glaring self, But my object is Northward of my location.

[smiller]

If someone advised you to “not use any filtering” without any condition or target dependency, then that was poor advice, or at the minimum, incomplete advice.   Here is a more complete version if I was to give you an answer:

 

First I’ll use a couple of definitions:

 

1) “No filter’ includes using just a UV/IR cut filter, which the ASI2600MC has built in.

 

2) “Light pollution filter” is a multibandpass filter that lets in a fairly broad spectrum of light including the important narrowbands (ex: Ha, Oiii) but cuts most of the narrowbands from certain types of manmade lighting such as Sodum Vapor and mercury Vapor.

 

3) A Narrowband filter is a filter that is intended to only let specific narrowbands through (typically only Ha and Oiii),  but there are others that let in 4 narrow bands or Oiii/Sii, but then cuts out as much of the other wavelengths as possible.

 

 

 

1) The optimum filtering is highly target dependent and somewhat sky condition dependent:

 

A) If shooting a narrowband target (like Veil Nebula that you showed), then by all means a filter that lets bands like Ha and Oiii through but blocks as much of the other light is beneficial.  In fact, the narrower the filter the better, as long at it still lets in Ha and Oiii without attenuating those two bands much.   

 

This is true regardless of whether the filter is a “Light Pollution Filter” or a “Narrowband filter” per my definition above.   So since you where shooting a narrowband target (Veil Nebula) then filtering is a huge benefit and the narrower the better.

 

B) If shooting broadband targets such as reflection nebula, interstellar dust, and most galaxies, it is generally recommended to shoot with no filter.  There is a debate on whether “Light pollution Filters” provide any benefit, but even those that have tested with a controlled side by side test, between “No FIlter” and a “Light Pollution Filter”, usually sees little to no benefit in the tests I’ve seen.   This isn’t universal as there are reports that indicate some modest general benefit in very light polluted skies.   Most that advertise a large benefit are reporting from anecdotal testing and not side by side testing with the same equipment and exact same sky conditions (i.e. at the same time on the same night, same target and equipment). 

 

 

2) Sky conditions may also impact the desire for filtering:

 

A) In extremely dark skies, (Ex: Bortle 1/2) you may desire no filter even on narrowband targets because with no filter you gain some benefits on the quality of your stars, background galaxies, interstellar dust, mixed narrowband/reflection targets, additional narrowbands that a narrowband filter may cut, less risk of reflections, and the fact that you don’t attenuate the narrowband signal as much.   This is highly situation and imaging goal dependent as there are people that still signifantly benefit from narrowband filters even from darker skies.

 

B) In extremely light polluted skies with a lot of man-made narrowband emissions, it’s quite possible that “Light pollution filters” may provide some benefits for broad band targets.   Again this is debated, but given that these filters do cut the manmade narrowband light, it’s logical that with enough of this lighting, they should provide some benefit, sometimes at the cost of a bit more complex processing to restore natural colors.

Edited by smiller, 21 July 2024 - 09:18 AM.

[PIEJr]

If someone advised you to “not use any filtering” without any condition or target dependency, then that was poor advise, or at the minimum, incomplete advice.   Here is a more complete version if I was to give you an answer:

 

First I’ll use a couple of definitions:

 

1) “No filter’ includes using just using a UV/IR cut filter, which the ASI2600MC has built in.

 

2) “Light pollution filter” is a multibandpass filter that lets in a fairly broad spectrum of light including the important narrowbands (ex: Ha, Oiii) but cuts most of the narrowbands from certain types of manmade lighting such as Sodum Vapor and mercury Vapor.

 

3) A Narrowband filter is a filter that is intended to only let specific narrowbands through (typically only Ha and Oiii),  but there are others that let in 4 narrow bands or Oiii/Sii) but then cuts out as much of the other wavelengths as possible.

 

 

 

1) The optimum filtering is highly target dependent and somewhat sky condition dependent:

 

A) If shooting a narrowband target (like Veil Nebula that you showed), then by all means a filter that lets bands like Ha and Oiii through but blocks as much of the other light is beneficial.  In fact, the narrower the filter the better, as long at it still lets in Ha and Oiii without attenuating those two bands much.   

 

This is true regardless of whether the filter is a “Light Pollution Filter” or a “Narrowband filter” per my definition above.   So since you where shooting a narrowband target (Veil Nebula) then filtering is a huge benefit and the narrower the better.

 

B) If shooting broadband targets such as reflection nebula, interstellar dust, and most galaxies, it is generally recommended to shoot with no filter.  There is a debate on whether “Light pollution Filters” provide any benefit, but even those that have tested with a controlled side by side test, between “No FIlter” and a “Light Pollution Filter, usually sees little to no benefit in the tests I’ve seen.   This isn’t universal as there are reports that indicate some modest general benefit in very light polluted skies.   Most that advertise a large benefit are reporting from anecdotal testing and not side by side testing with the same equipment and exact same sky conditions (i.e. at the same time on the same night). 

 

 

2) Sky conditions may also impact the desire for filtering:

 

A) In extremely dark skies, (Ex: Bortle 1/2) you may desire no filter even on narrowband targets because with no filter you gain some benefits on the quality of your stars, background galaxies, interstellar dust, mixed narrowband/reflection targets, additional narrowbands that a narrowband filter may cut, less risk of reflections, and the fact that you don’t attenuate the narrowband signal as much.   This is highly situation and imaging goal dependent as there are people that still signifantly benefit from narrowband filters even from darker skies.

 

B) In extremely light polluted skies with a lot of man-made narrowband emissions, it’s quite possible that “Light pollution filters” may provide some benefits for broad band targets.   Again this is debated, but given that these filters do cut the manmade narrowband light, it’s logical that with enough of this lighting, they should provide some benefit, sometimes at the cost of a bit more complex processing to restore natural colors.

It is a given to me, that if a filter is built in, The UV/IR cut filter, it is not something removable. So, it is given that the camera can only have additional, or no filters added to the light path to the sensor.

 

Currently I only have the one Antila Quad Band light pollution filter to play with.

Technical Specifications:

Wavelength:
H-alpha: 656.3nm
S-II: 671.6nm, 672.4nm
O-III: 495.9nm, 500.7nm
NII: 658.3nm, 654.8nm
Peak Transmission: 92%
Blocking: ≥OD4@ 300-1050nm
Filter Thickness: 2mm+/-0.05mm
Thread: Male M48x0.75

 

I do have an array of filters in 1.25", but they are somewhat useless for this sensor. So, I got a filter drawer for this beast.

My past experiences with my other OSC cameras taught me I typically liked the results of using my Baader HA7nm filter. And I did not use the OIII or SII enough to make them worth buying for this ASI 2600MC.

But I do live in a B7-9 area (depending on which way I turn. ) So LP filters were an advantage to me. 

 

I did find this thread about the ASI 2600MC camera, where I got that NO FILTER notion from. 

But I truly believe it is dependent on a fellow's LP index.

 

Anyway, my experiment is to be continued...    

[idclimber]

It is a given to me, that if a filter is built in, The UV/IR cut filter, it is not something removable. So, it is given that the camera can only have additional, or no filters added to the light path to the sensor.

 

Currently I only have the one Antila Quad Band light pollution filter to play with.

Technical Specifications:

Wavelength:
H-alpha: 656.3nm
S-II: 671.6nm, 672.4nm
O-III: 495.9nm, 500.7nm
NII: 658.3nm, 654.8nm
Peak Transmission: 92%
Blocking: ≥OD4@ 300-1050nm
Filter Thickness: 2mm+/-0.05mm
Thread: Male M48x0.75

 

I do have an array of filters in 1.25", but they are somewhat useless for this sensor. So, I got a filter drawer for this beast.

My past experiences with my other OSC cameras taught me I typically liked the results of using my Baader HA7nm filter. And I did not use the OIII or SII enough to make them worth buying for this ASI 2600MC.

But I do live in a B7-9 area (depending on which way I turn. ) So LP filters were an advantage to me. 

 

I did find this thread about the ASI 2600MC camera, where I got that NO FILTER notion from. 

But I truly believe it is dependent on a fellow's LP index.

 

Anyway, my experiment is to be continued...    

The ASI2600mc has the UV/IR filter window (D60 UV IR-CUT protect window). The 2600mm uses a different one with a wider bandpass (D60 AR protect window). Both are available as replacements and are pretty easy to install. 

 

One reason you might switch would be if you wanted a better UV/IR filter that is also parafocal with the narrowband filters in common use. Then when you switch you do not have to worry about backspace changes due to filter thicknesses. Just add a 2" UV/IR on broadband targets with a filter drawer, and change to the narrowband on emission targets. 

 

I have no idea if anyone does this, and I have no need as my 2600mc is used for broadband mostly on my SCT. 

[Sacred Heart]

PIEJr,

 

To me, this is an eye opener.   Right now I am a bortle 5 maybe 6, but that will soon change with all the building that is going on here.   That top picture, with filter, is WOW.

 

Thanks for posting.

 

Joe

[PIEJr]

PIEJr,

 

To me, this is an eye opener.   Right now I am a bortle 5 maybe 6, but that will soon change with all the building that is going on here.   That top picture, with filter, is WOW.

 

Thanks for posting.

 

Joe

Thanks Joe!

I like it too (the top image). I chose this object because of how that came out. But the reddish tint to a lot of the smaller stars made me wonder if time adjustments might help.

 

Tonight I'm taking a run of 300s (5 Min) images, 35 ea, No Filter, but already the increased time is not improving anything.   I would have thought it would. Still, I'm going to run it out.

Tomorrow night I'm thinking of going to 600s exposures (10 minutes). And doing that for w/filter and wo/filter.

 

I'm not much of one for calculations because there are way to many variables in play. So I take a shot and see if I like it.

I'm thinking I like with the Quad filter in the filter drawer, for my particular light pollution. I tend to find something I like, then shoot everything the same way.

But in my experience's, longer has worked better than shorter. LOL! A friend told me once I stacked with time. 

 

The few times I've been to darker skies the numbers of stars confuse me.   

 

Thanks Joe!

Edited by PIEJr, 21 July 2024 - 12:25 AM.

[PIEJr]

The ASI2600mc has the UV/IR filter window (D60 UV IR-CUT protect window). The 2600mm uses a different one with a wider bandpass (D60 AR protect window). Both are available as replacements and are pretty easy to install. 

 

One reason you might switch would be if you wanted a better UV/IR filter that is also parafocal with the narrowband filters in common use. Then when you switch you do not have to worry about backspace changes due to filter thicknesses. Just add a 2" UV/IR on broadband targets with a filter drawer, and change to the narrowband on emission targets. 

 

I have no idea if anyone does this, and I have no need as my 2600mc is used for broadband mostly on my SCT. 

I likely won't ever, Dave.

I'm not one to tinker with the inner workings of such expensive items.

Not that I'm afraid too.

I follow Martha's advice, "If it works, don't fix it."

[mrlovt]

To me, this is an eye opener.   Right now I am a bortle 5 maybe 6, but that will soon change with all the building that is going on here.   That top picture, with filter, is WOW.

 

\I like it too (the top image). I chose this object because of how that came out. But the reddish tint to a lot of the smaller stars made me wonder if time adjustments might help.

 

Tonight I'm taking a run of 300s (5 Min) images, 35 ea, No Filter, but already the increased time is not improving anything.   I would have thought it would. Still, I'm going to run it out.

Tomorrow night I'm thinking of going to 600s exposures (10 minutes). And doing that for w/filter and wo/filter.

 

I'm not much of one for calculations because there are way to many variables in play. So I take a shot and see if I like it.

I'm thinking I like with the Quad filter in the filter drawer, for my particular light pollution. I tend to find something I like, then shoot everything the same way.

But in my experience's, longer has worked better than shorter. LOL! A friend told me once I stacked with time. 

 

The few times I've been to darker skies the numbers of stars confuse me.   \

There's no doubt that the nebulosity really stands out in the top image.  Nice shot!

 

My backyard is in about bortle 8, and getting worse day by day, sadly.  These filters for OSC cameras, they really do help. I use the L-eXtreme, and would love to try that quad band.  It's a similar idea, narrow bandpass tuned to the frequencies around emission nebulae, not allowing most of the light pollution through.  When I use the filter, I can ealily go 180-300 second exposures and have great data to work with.  If I use no filter or a general LP filter like the L-Pro, I find LP overwhelms the sensor after 30-60 seconds.  Keep experimenting and keep posting your results!

[17.5Dob]

Who told you to not use a filter ? The Veil Nebula is an emission nebula, so even from a pristine dark site, it will still benefit from a filter, and the narrower the bandpass the better.

Trying to filter reflection nebula or galaxies which are broadband targets is where you will run into problems and they can actually cause poorer results than using no filter.

[gsaramet]

This might be interesting. I'd love to see: 

 

- a proper broadband target - a galaxy would do

- same integration time for both LP and UV/IRcut filters

- proper sub exposures for both targets - a couple hundreds pixels clipped for subs. 

LE: 

-edited to similar histograms with editing details

 

In my Bortle 9 I found no use for the LP L-Pro filter. 

Edited by gsaramet, 21 July 2024 - 06:07 AM.

[smiller]

This might be interesting. I'd love to see: 

 

- a proper broadband target - a galaxy would do

- same integration time for both LP and UV/IRcut filters

- proper sub exposures for both targets - a couple hundreds pixels clipped for subs. 

LE: 

-edited to similar histograms with editing details

 

In my Bortle 9 I found no use for the LP L-Pro filter. 

There is a YouTube video of someone that did exactly this:

 

1) side by side setup of the exact same equipment operating at the same time except one with a LP and one with just UV/IR cut.

2) broadband targets (Galaxy, etc…)

3) proper exposures, same integration time

 

What he found was no material overall improvement, but I can’t find the video!   I’ll keep looking, perhaps someone else can locate it.

 

there are other YouTube videos of people that do more ad-hoc testing with poor controls, either testing on different nights or with different equipment or only testing with the filter and not doing a complete side-by-side test.  or they’re testing on a narrowband target not a broadband target.  I only found one YouTube video of someone that actually did a good controlled experiment on a broadband target and I’m so mad I can’t find it now.

 

I had even commented on the video that of all the YouTube comparisons of light pollution filters out there on  broadand targets, this is the only person that did a proper well controlled experiment.

Edited by smiller, 21 July 2024 - 01:00 PM.

[PIEJr]

Who told you to not use a filter ? The Veil Nebula is an emission nebula, so even from a pristine dark site, it will still benefit from a filter, and the narrower the bandpass the better.

Trying to filter reflection nebula or galaxies which are broadband targets is where you will run into problems and they can actually cause poorer results than using no filter.

Post 3 above; https://www.cloudyni...ter/?p=13578687

 

"I did find this thread about the ASI 2600MC camera, where I got that NO FILTER notion from.

But I truly believe it is dependent on a fellow's LP index."

 

Anyway, that thread seemed to have an overwhelming notion to not use filters with an ASI2600MC camera.

Me being the "Curious George" monkey I am, I like to do my impromptu experiments.

This was one I could easily try. Although I only have the one single filter.

So now, I'm continuing the task, an impromptu night after night curiosity visit to the same object to try my own experiment.

 

The results are none but my own. They could not really be duplicated because another's place would bear different conditions to begin with. And I accept even mine will have variation.

And different equipment. To me, this is why each of us plying this field of Deep Space Astrophotography will always get separate results. Not a bad thing, but a fact.

Any Beginner could, if having the same camera and filter, could do a with/without comparison. But it is more of a curiosity experiment, than scientific.

Very little of taking images from the Earth into outer space is repeatable.

 

Last night I did the same experiment, but with my normal time for exposure. 300s and 35 each. I'm processing last nights to include here in comparison to the first set of No Filter final image. (Clarification: No Filter added by me.) Just an empty drawer slid into the holder.

The appearance I saw was very much like the 150s and 70 each, shown in the second image in post 1.

I'm using the same library files of Bias, Flats, Darks to stack the lights. So those are consistent. And the same Auto settings in Photoshop Elements 12. So at least I'm being as consistently inconsistent as I can with this experiment.  

Here's the layout so far:

 

 

 

 

For me, my results encourage me to use the Antila Quad LP Filter.

I will say I'm not a fan of brighter, more stark high contrasting images. But there is something to see in them and the details that pop forth.

Being as I'm using a filter drawer, it is very easy to add or remove any filters I might try.

People can say what they will about filters. I say, try it. Then show us what you find with them.

 

I've tried different filters all along in the past 10+ years. LP filters have often been in front of the various cameras I've owned. As have narrowband filters.

Each can have its effect on your outcome. Give it a try. 

[smiller]

Again, this is a narrowband target.  Absolutely a filter, like what you are using, is a drastic improvement for those targets.  The debate and confusion over filter effectiveness is when used to capture broadband targets.

Edited by smiller, 21 July 2024 - 06:25 PM.

[bbasiaga]

This filter and its cousin the Tri-band are interesting.   For us using the 2600MC with its built in UV/IR filter, the Quad band loses its 4th band, which is in the IR spectrum and so becomes a tri-band.  But the bands are in a different place than the Tri-band offering from the same manufacturer.   

 

For the Veil, it makes all the sense in the world to use this.   I've seen some limited testing on broadband targets, both here and on YT.  I think Dark-ranger on youtube did one.  But he's got a confound or two in his experiment too (hopefully I'm recalling the right video, if not I apologize) in that one of his cameras is IR sensitive and the other is not.   Sitting here in B7, it does intrigue me there could be some viable help for broadband targets.   

 

I just shot the veil with my duo-band L-enhance.  It came out well but I need to finish processing it.  

 

 

Brian

[PIEJr]

 

This filter and its cousin the Tri-band are interesting.   For us using the 2600MC with its built in UV/IR filter, the Quad band loses its 4th band, which is in the IR spectrum and so becomes a tri-band.  But the bands are in a different place than the Tri-band offering from the same manufacturer.   

 

For the Veil, it makes all the sense in the world to use this.   I've seen some limited testing on broadband targets, both here and on YT.  I think Dark-ranger on youtube did one.  But he's got a confound or two in his experiment too (hopefully I'm recalling the right video, if not I apologize) in that one of his cameras is IR sensitive and the other is not.   Sitting here in B7, it does intrigue me there could be some viable help for broadband targets.   

 

I just shot the veil with my duo-band L-enhance.  It came out well but I need to finish processing it.  

 

 

Brian

I hope to see your results!

 

10+ years ago the first dual use filters were first immerging. They were expensive, unknown, new rocks to throw at this imaging nightmare of Astrophotography.

At the time, Baader and their HA7nm was the pick to subdue light pollution and "pop" the reds in various nebulae. IIRC there were 2 HA filter picks back then. (7, obviously. And a 12. but don't quote me on that.)

A close friend recommended a HA7nm to me to try and pull out more details and highlights. So, I gulped down the lump and ordered my first expensive filter, The Badder HA7nm in 1.25". Still have it, and it still does wonders for many nebula images as long as the sensor is small enough to be nestled behind it.

That was back when the world was young, and the hot camera was an Orion G3 OSC. The G3 had a following, but my experience was not good.

 

Times change and equipment, too.

I spent a stint behind an Atik Infinity OSC, and an ASI 1600MM Pro, trying to force myself to find success in painting B&W images. Never did.

I actually bought the 1600 just as the 2600 was beginning to hit the market

Finally, years later, I hung my head and invested in my ASI 2600MC Pro. AHHH, instant return to successful color images.

 

Running it through my ASI EFW that came as a part of the package of the highest end ASI 1600MM Pro kit I realized the 1.25" filters pinched the result too much for me to just pick out the targeted Nebula, and I'd have to relented to larger filters. If you're going to take the leap, may as well run at it and make it a good one.   

So, to future proof whoever takes the helm of my Astro Ship when I'm dead and gone will have my collection of filters Big, and small. 

So far, my "big" collection is a single Antila Quad Light Pollution Filter.

 

"The Antlia Quad Band Anti-Light Pollution Filter is a light suppression filter for color and monochrome cameras. It is able to shoot most deep sky objects like galaxies,

reflection nebulae, emission nebula, and star clusters from a Bortle 8 location to Bortle 1 as its spectral transmission passes through visible light region, near-ultraviolet (NUV) and near-infrared (NIR) region."

 

Go BIG or go home. 

And my first ever multi-banned filter.

I don't care about the IR filter the factory installed, or if or if not, it negates the IR block of the quad band filter. Chances are the two in combination will catch what the other misses.

Chances are the quad band will be around a lot longer than the 2600 will live, given my experience with these China originated cameras.

One thing that has held true for me, is most of the stuff from there will only slightly outlive its warranties. Especially since I'm a power user. If the night looks good, my poop is grouped and running.

My stuff does not sit around in the house looking like museum pieces.

 

Anyway, I'm happy with my ASI 2600MC Pro, 2" Quad Band filter, and the Blue Fireball 2" Filter Drawer.

A new pile of fun to play with.

 

I did think hard on if I wanted to relinquish the control single filters, but in the end the alure of these combo-mombos won me over. Just like returning to the instant gratifications of using a color camera. Despite the RGGB sensors, arranged in a square or rectangular pattern to be bathed in light through round apertures, round filters. Much like done in the 1800's with tin-type square plates, square boxes, and a round hole. Have we really progressed?

Curious George punched the buy button on the Quad Band.

So far, so happy. In spite of the semantics of the math professors trying to enlighten everybody with their calculations which only slightly apply, because they are not here beside me running the exact same equipment at the exact same time. It's easy to taut a bunch of paper calculations, but it does not prove out in practical application.

All the variables including the tolerances between the physical attributes of each item, coupled with trying to operate through the soup of our atmosphere negates the best laid plans of mice and men.

That actually does little to stop me from enjoying my choices and the variables I can crank in, which this thread was aimed at. Simple variations anybody could try.

 

Anyway, I'm back to my Kentucy Windage of 300s exposures, 30-35 images, and very light processing. And using my library of Bias, Flats, Darks mixed into the Lights for calibration.

Then save the result as a Web ready jpg to hang on the web.

And everybody watching the fireworks show went Oooo, Ahhhh. 

LOL! 

 

600s (10 minute) X 22 exposures. I got a cable snag. Ratzen-Fratzen, Fratzen-Ratzen.

Ca-Ca- Occures....

 

Edited by PIEJr, 24 July 2024 - 05:08 PM.

[TelescopeGreg]

I don't care about the IR filter the factory installed, or if or if not, it negates the IR block of the quad band filter. Chances are the two in combination will catch what the other misses.

Chances are the quad band will be around a lot longer than the 2600 will live, given my experience with these China originated cameras.

Just curious, do you have any images that are (or should be) strong in that 4th band, as a way to gauge the effect of the internal UV/IR filter?  I imaged for a couple of years with an unmodified DSLR that was annoyingly blind to Ha, yet I still got some interesting images of Ha-rich targets.  The effect of the two filters shouldn't be zero transmission, right?
 

[gsaramet]

Since you insist, here's my two Veils

 

First one is 2 years old, unmodded DSLR, no filter. As you can see it's quite indifferent to Ha. I wasn't very picky with my file naming and logging and I am a bit too lazy to dig the external HDD with the files. It was shot in August, it's a single night project, I have altitude requirements in my yard due to buildings, so it can't be more than  3-4 hours integration time. Bortle is 9, scope is f/4. Of course, taken during the summer, when a DSLR is at it's worst. 

 

 

 

Second one is with 533 MC Pro and ALP-T duoband filter. Same scope. 2 hours, 10 mins. Proper sensor temperature.

 

 

Looking at my two images and especially at the Oiii signal (which should be same-ish) my conclusion is that The Veil is a shiny enough target to imagine broadband if one chooses to do so. I see absolutely no signal outside the Ha and Oiii emission bands (and I don't really expect to see it with such a short broadband integration time).  Therefore ANY filter that allows wavelengths outside the Ha and Oiii bands is suboptimal.

 

What I know I'll find if I use a light pollution filter on this object? It will probably mess up my star colors. It will improve the contrast on the veil - the bigger the bandcut, the better contrast. It won't affect the colors of the DSO, because it only emits in Ha and Oiii.

 

What I found out a light pollution filter does on a broadband target, such as a galaxy? Mess up stars and loose signal in bandcuts, while improving a bit the contrast.

 

I really am curious if a "modern" tri or quadband light pollution filter has a better balance of benefits/disadvantages, not to mention costs. But for that one should make a proper test, as I described in post #10.

[Andros246]

I'm sure its been said here already but i'm going to say it again but them marketing this a "light pollution filter" is just so misleading.

 

A narrowband filter whether quad/duo/tri/single band is completely different than a "light pollution filter"

 

Marketing kills me it introduces SO MUCH CONFUSION

Edited by Andros246, 25 July 2024 - 09:29 AM.

[gsaramet]

I'm sure its been said here already but i'm going to say it again but them marketing this a "light pollution filter" is just so misleading.

 

A narrowband filter whether quad/duo/tri/single band is completely different than a "light pollution filter"

 

Marketing kills me it introduces SO MUCH CONFUSION

While I would agree they are not exactly the same as old school LP filters, I would say they aren't narrowband filters, either. The bandpass seems to be about 50nm in visible/NIR and about 30nm in NUV. That's not narrow, by a large margin. And, as you say, they market those as LP filters. 

[PIEJr]

Just curious, do you have any images that are (or should be) strong in that 4th band, as a way to gauge the effect of the internal UV/IR filter?  I imaged for a couple of years with an unmodified DSLR that was annoyingly blind to Ha, yet I still got some interesting images of Ha-rich targets.  The effect of the two filters shouldn't be zero transmission, right?
 

Not currently, Greg.

I donno. Basically, I don't fuss with the math or semantics of these filters.

I just point and shoot, if you will. About the time the best laid plans of Mice and Men come together, everything changes in this sport.

Especially, and most often the atmosphere we have to breach to try and get a picture through, being ants scurrying around on the ground. 

 

I'm not a Lab, no measuring equipment or Spectrometers. (And no plans to begin with them. I'm retired. And trying to get away from all the traps of my past professional life.   )

I do have many 1.25" filters that worked fine for my march of cameras, including my ASI 1600MM Pro. Two fat filter wheels full. Surplus of prior attempts.

They simply are too small for this ASI 2600 MC Pro, even for centered, cropped use.

 

So, like my mount computer, I find what looks best for what I want to filter out, and give it a shot. As in this case. I globed onto my Antila quad filter to try and knock down some of the Light Pollution in my immediate area.

How it does it, how much and exactly what it is cutting out is of little importance to me. What is important is what I see on my computer display (I almost wrote screen. Throwback to the CRT days. LOL!)

If it is of interest, here is a link to the graph they use to display the bands the filter is working in. https://agenaastro.c...rum_curve_1.jpg

(I didn't bury the link in words like usual, because I realize some don't understand hyper text links.)

Anyway, my interest is in the results I get, for my equipment, in my location, which is most likely not the same as others for their situations. Especially beginners trying to get a grasp on this. Clear as mud.

 

?"Mud's not clear." Exactly.

And Astrophotography is not an exact science, either. But it can be a lot of fun.

Never forget where the delete key is. 

[PIEJr]

Since you insist, here's my two Veils

 

First one is 2 years old, unmodded DSLR, no filter. As you can see it's quite indifferent to Ha. I wasn't very picky with my file naming and logging and I am a bit too lazy to dig the external HDD with the files. It was shot in August, it's a single night project, I have altitude requirements in my yard due to buildings, so it can't be more than  3-4 hours integration time. Bortle is 9, scope is f/4. Of course, taken during the summer, when a DSLR is at it's worst. 

 

 

 

 

Second one is with 533 MC Pro and ALP-T duoband filter. Same scope. 2 hours, 10 mins. Proper sensor temperature.

 

 

 

Looking at my two images and especially at the Oiii signal (which should be same-ish) my conclusion is that The Veil is a shiny enough target to imagine broadband if one chooses to do so. I see absolutely no signal outside the Ha and Oiii emission bands (and I don't really expect to see it with such a short broadband integration time).  Therefore ANY filter that allows wavelengths outside the Ha and Oiii bands is suboptimal.

 

What I know I'll find if I use a light pollution filter on this object? It will probably mess up my star colors. It will improve the contrast on the veil - the bigger the bandcut, the better contrast. It won't affect the colors of the DSO, because it only emits in Ha and Oiii.

 

What I found out a light pollution filter does on a broadband target, such as a galaxy? Mess up stars and loose signal in bandcuts, while improving a bit the contrast.

 

I really am curious if a "modern" tri or quadband light pollution filter has a better balance of benefits/disadvantages, not to mention costs. But for that one should make a proper test, as I described in post #10.

Nice images, Gabriel. But I do wonder if the Vail you have posted is the Vail I've posted. I think not.

Yep, I tried my DSLR several times in several ways, but before even getting my first mount and telescope I knew I would not be using my DSLR. Mine was already more half-way worn out, and I knew Astrophotography would have had it laying on the ground dead and worn out. 

So, I entered the field with my entry level OSC Astro camera from the start. I have bounced back to use my DSLR for comets or other interesting things in our night skies.

But I prefer dedicated Astro Cameras for my interest in DSO, Nebula specific imaging.

 

These multi band filters always interested me. But were not a priority in my days of filter acquisition's. Until this newest camera entered my array of equipment. The multi-band filters came along just about the time I was in the middle of my 1.25" filter collection ~10 years ago.

And they met the same curiosity and resistance these latter day multi-band filters are.

I particularly have always been interested in filtering the light pollution around my location. According to the LP maps, I figure I'm in a Bortles 7-9 area.

So that was my intent for this Quad Band filter. And the price point also influenced my choice. Not the particular bands it was filtering, but the light pollution it might knock down for me.

 

The way it made my subject "pop" is a secondary interest to me, and this thread. But it is apparent many like the brighter colors given when comparing Filter VS: No Filter.

I must admit, the skittles colors have grown on me too. This old dog can entertain new tricks. LOL.

But what I get is what I get. The brighter colors and definition is interesting, and might look better on other displays.

 

I don't see me buying others of these Multi-band filters anytime soon. I'll likely just go on my merry way grabbing images of other Nebulae oddities as I find them creeping into view.

I use Stellarium as my Planetarium program with NINA. The two interact very well for me. So I have an idea what my previews will be as the camera collects the exposures.

This was my intended target, and you've seen what I collected. Not too far off.

I tend to go by the Old School names I first encountered, such as, "The Witches Broom". When I see that, I immediately know what I will see when I open a file. NGC 6960 is a bit vague to me.

 

Anyway, nice images. Thanks for sharing.

[PIEJr]

I'm sure its been said here already but i'm going to say it again but them marketing this a "light pollution filter" is just so misleading.

 

A narrowband filter whether quad/duo/tri/single band is completely different than a "light pollution filter"

 

Marketing kills me it introduces SO MUCH CONFUSION

Oh, absolutely, Andros!

What is researched and developed, takes on an entirely ugly head by the time it surfaces as available to us the consumers.

None the less, it is presented as a Light Pollution Filter. I leave it up to you to present your case otherwise.

Did you see the image link above? https://agenaastro.c...rum_curve_1.jpg

Things like that give me a better idea of what the engineering was trying to give us. How well it works at our location, with our conglomeration of equipment, and the intensity of our light pollution, can vary widely from the "Drawing Board".

 

But yep, Marketing's job is to package the pill in such a way as to get us to open our purses and put our monies on the barrelhead to buy the wares they are tasked to push on us.

Lying is one of their first and foremost skills.

 

Mine is to take the said pill and see if it works for me. In a very simplistic way.

Seems to make me happy. I've always wondered about these "universal solder" filters. Now I have >one< to play with.

I can choose to put it in the light stream aimed at my camera, or not.

Simple and easy, too me.

(And simply repeatable by any other beginners)

Edited by PIEJr, 25 July 2024 - 01:33 PM.

[freestar8n]

I agree it's misleading to call this a "light pollution filter."  In order for a filter to work it needs to block out more of the bad stuff without blocking too much of the good stuff.  When it comes to trying to image a broadband target - if your light pollution is also broadband there isn't much you can do - and standard advice just not to use any filter at all is a good one (except for UV/IR blocking - which is probably needed with OSC).

 

The two types of filters that will have a chance to work are either emission line *passing* or emission line *blocking*.  They don't have to be extremely narrow to be emission line filters - as long as they are centered on certain emission lines that are either "good" or "bad".

 

Unfortunately, nowadays most people don't have "bad" emission lines from street lighting that they can preferentially block.  Light pollution tends to be broadband - so for things like galaxies, dust, and globular clusters - there is no filter that can help.

 

But if you do have sodium vapor or mercury halide light pollution - you may be able to preferentially block those emission lines.

 

And no matter what the light pollution, you can always preferentially *transmit* emission lines with big benefit when imaging a nebula.

 

But if a filter doesn't specifically *block out* light pollution (rather than preferentially transmit nebulosity) I wouldn't call it a light pollution filter.

 

A real "light pollution filter" would mainly block out light pollution - and that would help with imaging any object and not just a nebula.

 

Frank

Edited by freestar8n, 25 July 2024 - 09:44 PM.

[PIEJr]

I agree it's misleading to call this a "light pollution filter."  In order for a filter to work it needs to block out more of the bad stuff without blocking too much of the good stuff.  When it comes to trying to image a broadband target - if your light pollution is also broadband there isn't much you can do - and standard advice just not to use any filter at all is a good one (except for UV/IR blocking - which is probably needed with OSC).

 

The two types of filters that will have a chance to work are either emission line *passing* or emission line *blocking*.  They don't have to be extremely narrow to be emission line filters - as long as they are centered on certain emission lines that are either "good" or "bad".

 

Unfortunately, nowadays most people don't have "bad" emission lines from street lighting that they can preferentially block.  Light pollution tends to be broadband - so for things like galaxies, dust, and globular clusters - there is no filter that can help.

 

But if you do have sodium vapor or mercury halide light pollution - you may be able to preferentially block those emission lines.

 

And no matter what the light pollution, you can always preferentially *transmit* emission lines with big benefit when imaging a nebula.

 

But if a filter doesn't specifically *block out* light pollution (rather than preferentially transmit nebulosity) I wouldn't call it a light pollution filter.

 

A real "light pollution filter" would mainly block out light pollution - and that would help with imaging any object and not just a nebula.

 

Frank

Hi Frank,

I didn't name it a Light Pollution filter, they did.

I just bought it. LOL!

 

In post 1, I have an image of with, and without, the Antila Quad filter. So there is a comparison of both sides of that coin. Then things ramble on from there.

 

It does seem to help, although I'm not really one for such "Pop" in my images. But many folks do like that sort of bright and colorful imaging.

 

Where I live and play, the HPS and other area lighting has for all intents and purposes been changed to LED technologies. It is for the better, the high-pressure sodium (HPS) streetlamp in front of my home that sent glow everywhere. As much up and sideways as it did to the street.

The power company basically blanket replaced all the luminaires with directed LED units. Much better than the old lighting. I don't know much other than that. so no Kelvin or other details, just that it is a LOT better than the old stuff.

 

Behind me is a condominium complex beyond the mote. (OK, a concrete drainage ditch) it was somewhat of a war with their crappy area lighting. They stuck two 1000-watt Metal Halide on one of the buildings, and they were aimed right in the windows of 5 or more homes on our side of the ditch. Enough! I got to work and discovered our city has a lighting code that states the outside lighting of your home cannot spill into the neighbors yards or light up their homes.

The code enforcement officer, Lisa. paid a visit and observed for herself the obnoxious 2000 watts of white metal halide lighting shining in our windows all night. She offered to cite the HOA of the big complex.

The fixtures were aimed down the building at the ground.

The HOA retaliated and installed obnoxiously bright LED lighting in All of the outside fixtures so the sky literally glowed bright as the sky above a prison at night.

I continued to hide where I still do with an overgrown ugly hedge of ivy standing about 4' over a 5 foot concrete block wall.

When we replaced our patio cover and remodeled the yards, I found out I could put a "topper" on the back block wall. So a day or two before I cut down and tore out all the ivy on my side of the wall. As I was progressing along the tall ivy wall, removed of its anchorage on my side of the wall, collapsed to the roadway of the ditch where it had grown from. Good riddance!

Our 3' high fence wall topper finished the job proper. No more of their crappy light spilling into our yard.

They must have bought cheap LED lighting, because now much of it has half-lifed and is nowhere near as obnoxious as it was when new. It's not glaring white light into the sky like it used too.

 

So, there you have it, most of the light pollution I deal with is LEDs and neighbors dumb enough to think burning outside lights all night are going to save them from some street urchin breaking into their homes.

I'm not going to split hairs about trying to buy every filter on the market to block every type of obnoxious human light pollution around me. But I did get this cool Quad filter and it appears to work fine.

So, I'll keep using it. You can run with no filter if you'd like. But it just does not work well where I am. 

[gsaramet]

Nice images, Gabriel. But I do wonder if the Vail you have posted is the Vail I've posted. I think not.

[...]

 

I particularly have always been interested in filtering the light pollution around my location. According to the LP maps, I figure I'm in a Bortles 7-9 area.

So that was my intent for this Quad Band filter. And the price point also influenced my choice. Not the particular bands it was filtering, but the light pollution it might knock down for me.

 

[...]

 

I tend to go by the Old School names I first encountered, such as, "The Witches Broom". When I see that, I immediately know what I will see when I open a file. NGC 6960 is a bit vague to me.

 

Anyway, nice images. Thanks for sharing.

Sure, it's not the same piece. However, they are part of the same astronomical event - Cygnus loop - and in the same part of the sky. They should "work" similarly. 

 

I even planned the whole loop as a mosaic, and then I counted the 20 panels necessary with my rig and translated them into a few years of work. Not ready for that Should the planets align, I'll get next week a 2600 MC Duo, and that might change the calculations Fear those in Eastern Europe, clouds might be coming because of me!

 

Re: filters. As most people, I use them for what they do, and it's always a bit of compromise. I chose the ALP-T vs L-Ultimate for what I perceived as better halo's around stars. I then found out it's also easier to focus, because of larger bandpass. I use it on emission nebulae, where it nicely allows Ha and Oiii to pass and blocks everything else, as intended. Now, when under my skies (and yours too, as it appears), it would be nice to have something to improve things for the other targets - the broadband ones. My L-Pro does not. I was curious if the Quad band does. 

 

As a suggestion, if you like emission nebulae, try to borrow a duo-NB filter. It makes a huge difference, and the bands are down to 3 nm, not 50. 

 

Clear skies!