18 replies to this topic

[bldeagle1]

I have been looking to make the switch from Ha modified DSLR to a Monochrome cooled camera and filters. I have been reading a lot about different filter brands and I see over and over that people say Astrodon filters are the best, but it seems nobody sells them and I can not find a company website, so wondering if they are out of business??

 

If so, alternative options? Baader? Astronomik? Chroma? Are the better ones parfocal? is the 3.5NM worth the extra expense over 6.5NM?

 

If not, where the heck do you find these magical filters?

 

Thanks

Edited by bldeagle1, 21 June 2024 - 12:08 PM.

[hyiger]

I have been looking to make the switch from Ha modified DSLR to a Monochrome cooled camera and filters. I have been reading a lot about different filter brands and I see over and over that people say Astrodon filters are the best, but it seems nobody sells them and I can not find a company website, so wondering if they are out of business??

 

If so, alternative options? Baader? Astronomik? Chroma? Are the better ones parfocal? 

 

If not, where the heck do you find these magical filters?

 

Thanks

I don't think they are still around. There are various threads on it here. One example: https://www.cloudyni...don-going-away/

 

Chroma are considered the best but they are $$$$. My recommendation is the Antlia Pro. I have a set and they are awesome. No halos. 

[psandelle]

Chroma are the equal.

Paul

[bldeagle1]

I don't think they are still around. There are various threads on it here. One example: https://www.cloudyni...don-going-away/

 

Chroma are considered the best but they are $$$$. My recommendation is the Antlia Pro. I have a set and they are awesome. No halos. 

Thanks, do you have both the LRGB and the SHO Pro filters? 

[hyiger]

Thanks, do you have both the LRGB and the SHO Pro filters? 

Yes, I have both sets. For LRGB you can cheap out on those. For SHO "you get what you pay for", i.e. I recommend going for one of the premium brands. 

[auroraTDunn]

That's sad to hear about Astrodon not being around I LOVE my set of LRGBHSO filters!

I have chatted with a few and made comparisons, cheap testing not hardcore that you'd really want to see, and found the Chroma's 3nm's pretty much the same my Astrodon's. Sadly so are the prices. The good news you get what you pay for!

[KGoodwin]

I have been very happy with my Antlia 3nm set and recently bought a second set of Antlia, the 2.8nm version, and I'm happy with those as well.  I have a set of Astrodon 1.25" 3nm from when I used an ASI1600 and they were definitely better than the Antlia 3nm, but I can't detect any difference between them and the Antlia 2.8nm set, which have much higher peak transmission.  My next set will probably be Chroma since my next acquisition is going to be a CDK14 with a full frame camera and I want to do everything with the buy once, cry once approach on that setup.

[hyiger]

I have been very happy with my Antlia 3nm set and recently bought a second set of Antlia, the 2.8nm version, and I'm happy with those as well.  I have a set of Astrodon 1.25" 3nm from when I used an ASI1600 and they were definitely better than the Antlia 3nm, but I can't detect any difference between them and the Antlia 2.8nm set, which have much higher peak transmission.  My next set will probably be Chroma since my next acquisition is going to be a CDK14 with a full frame camera and I want to do everything with the buy once, cry once approach on that setup.

I guess if you are getting a CDK, might as well get the Chroma. Very happy with my Antlia pros and also getting the 2.5nm now that they make them in 36mm unmounted. 

Edited by hyiger, 21 June 2024 - 01:35 PM.

[bldeagle1]

I have been very happy with my Antlia 3nm set and recently bought a second set of Antlia, the 2.8nm version, and I'm happy with those as well.  I have a set of Astrodon 1.25" 3nm from when I used an ASI1600 and they were definitely better than the Antlia 3nm, but I can't detect any difference between them and the Antlia 2.8nm set, which have much higher peak transmission.  My next set will probably be Chroma since my next acquisition is going to be a CDK14 with a full frame camera and I want to do everything with the buy once, cry once approach on that setup.

Did you mean the 2.5NM? I don't see a 2.8 version?

[ChrisWhite]

I have astrodon, Chroma and astronomik. For value proposition the astronomiks are my favorite, and what I'm using now. Specifically the deep sky rgb and the maxfr 6nm for narrowband. They are exceptional filters, no halos, no issues using with refractors and epsilon. If your LP doesn't require you to get a narrower bandpass than 6nm I would give them a serious consideration.

I'll never buy Chroma again... they are very expensive (and they are not far from where I live)

Astrodon, as mentioned isn't really around anymore. Used market if you want them.

Edited by ChrisWhite, 21 June 2024 - 01:41 PM.

[bldeagle1]

I have astrodon, Chroma and astronomik. For value proposition the astronomiks are my favorite, and what I'm using now. Specifically the deep sky rgb and the maxfr 6nm for narrowband. They are exceptional filters, no halos, no issues using with refractors and epsilon. If your LP doesn't require you to get a narrower bandpass than 6nm I would give them a serious consideration.

Thanks, I am Bortle 5 at my house, and most of the light pollution is to the West of our place (we're about 18 miles ESE of downtown Orlando)

Edited by bldeagle1, 21 June 2024 - 01:44 PM.

[KGoodwin]

Did you mean the 2.5NM? I don't see a 2.8 version?

They don't sell them as 2.8nm anymore.  They're the same as the 2.5nm but when they first came out they sold the 2" as 2.5nm and the 36mm as 2.8nm for whatever reason, probably because the manufacturing process wasn't perfected yet to guarantee 2.5nm and they used the ones that tested as meeting the 2.5nm spec on the higher margin, larger filters until they could increase the yield and transition the smaller ones to 2.5nm spec also.  There may also have been a slightly different manufacturing process.  What I found was that in the early batches at least the 36mm 2.8nm marketed ones had a higher peak transmission value than the 2.5nm ones.  I didn't actually want/need a narrower than 3nm pass band, I just wanted the higher peak transmission, so the 2.8nm was perfect for me.  From what I can tell the 2.5nm now have the same peak transmission or very close at least to what the 2.8nm ones did, so it's moot at this point.  Regardless, I think they're great filters.

 

Edit: one thing I forgot to add is that if you look at the passbands for the 2.5/2.8nm versions they're actually really similar to the Chroma 3nm filters.

 

Chroma 3nm Oiii, above 1%: 498.40-503.20; above 80%: 499.40-501.60

Antlia 2.5nm Oiii, above 1%: 498-503; above 80%: 499.25-501.45 (less precise because data is only provided as a graph, not raw)

 

Basically the same width, so the 2.5nm thing is a bit of a gimmick from Antlia, but here's an important thing:

 

Choma 3nm Oiii, peak transmission: 99.62%

Antlia 2.5nm Oiii, peak transmission: 96% (my measured filter curve that came with my set is actually about 98%)

Antlia 3nm Oiii, peak transmission: 92% now, but when I bought mine they only guaranteed 88% (my measured set is 91%, back then people reported as low as 85% in testing)

 

Edit2: I forgot to mention that peak transmission, pass band, and value outside of the passband are important not only because of the contrast of the image on the light you want, but also because of reflections.  If you're not passing the light it has to go somewhere.  Light reflected off the filter often is reflected back at the filter a second time.  If that light is passed it will become a halo.  The interaction between passband width, peak transmission, and the blocking outside the pass band is a complicated one as it relates to reflections, but suffice to say that the better controlled your filters are in passing all the light you want and nothing but the light you want the better off you'll be with halos.

Edited by KGoodwin, 22 June 2024 - 09:25 AM.

[Deesk06]

I have astrodon, Chroma and astronomik. For value proposition the astronomiks are my favorite, and what I'm using now. Specifically the deep sky rgb and the maxfr 6nm for narrowband. They are exceptional filters, no halos, no issues using with refractors and epsilon. If your LP doesn't require you to get a narrower bandpass than 6nm I would give them a serious consideration.

I'll never buy Chroma again... they are very expensive (and they are not far from where I live)

Astrodon, as mentioned isn't really around anymore. Used market if you want them.

Would you suggest getting a Chroma Oiii 3nm? I have the Astronomiks that you have and I love them, but I am in Bortle 7. I think a 3nm could be good for me, so maybe worth buying just the oiii, as I see no issue with the Astronomiks otherwise. I love them. 

[ChrisWhite]

Would you suggest getting a Chroma Oiii 3nm? I have the Astronomiks that you have and I love them, but I am in Bortle 7. I think a 3nm could be good for me, so maybe worth buying just the oiii, as I see no issue with the Astronomiks otherwise. I love them.

The Chroma is 3mm thick, while the astronomik is 1mm thick. If your system is sensitive to backspacing then you would not want to mix filter thicknesses.

I image in B3/4, so can't advise on whether the 3nm would be worth it. Generally, the worse the light pollution the greater the benefit for restricting bandpass.

Someone will likely chime in that is in a similar LP situation as you.

[KGoodwin]

I image in B3 and I have found the 3nm to be worthwhile. For me it’s not about cutting light pollution. It’s about moon resistance and contrast. I have noticed both to be better at 3nm.

[syxbach]

Chroma, especially, for LRGB, chroma still worth it. Just need to be patient to get good deal from 2nd hand market.

[andysea]

Yeah agreed Chroma and AD look the same to me, I own both.

Funny thing, when I bought Chroma, they were  the cheap alternative to Astrodon, before they jacked up their prices.

[bldeagle1]

They don't sell them as 2.8nm anymore.  They're the same as the 2.5nm but when they first came out they sold the 2" as 2.5nm and the 36mm as 2.8nm for whatever reason, probably because the manufacturing process wasn't perfected yet to guarantee 2.5nm and they used the ones that tested as meeting the 2.5nm spec on the higher margin, larger filters until they could increase the yield and transition the smaller ones to 2.5nm spec also.  There may also have been a slightly different manufacturing process.  What I found was that in the early batches at least the 36mm 2.8nm marketed ones had a higher peak transmission value than the 2.5nm ones.  I didn't actually want/need a narrower than 3nm pass band, I just wanted the higher peak transmission, so the 2.8nm was perfect for me.  From what I can tell the 2.5nm now have the same peak transmission or very close at least to what the 2.8nm ones did, so it's moot at this point.  Regardless, I think they're great filters.

 

Edit: one thing I forgot to add is that if you look at the passbands for the 2.5/2.8nm versions they're actually really similar to the Chroma 3nm filters.

 

Chroma 3nm Oiii, above 1%: 498.40-503.20; above 80%: 499.40-501.60

Antlia 2.5nm Oiii, above 1%: 498-503; above 80%: 499.25-501.45 (less precise because data is only provided as a graph, not raw)

 

Basically the same width, so the 2.5nm thing is a bit of a gimmick from Antlia, but here's an important thing:

 

Choma 3nm Oiii, peak transmission: 99.62%

Antlia 2.5nm Oiii, peak transmission: 96% (my measured filter curve that came with my set is actually about 98%)

Antlia 3nm Oiii, peak transmission: 92% now, but when I bought mine they only guaranteed 88% (my measured set is 91%, back then people reported as low as 85% in testing)

 

Edit2: I forgot to mention that peak transmission, pass band, and value outside of the passband are important not only because of the contrast of the image on the light you want, but also because of reflections.  If you're not passing the light it has to go somewhere.  Light reflected off the filter often is reflected back at the filter a second time.  If that light is passed it will become a halo.  The interaction between passband width, peak transmission, and the blocking outside the pass band is a complicated one as it relates to reflections, but suffice to say that the better controlled your filters are in passing all the light you want and nothing but the light you want the better off you'll be with halos.

Thanks! Were you concerned when you bought them about their "no returns for halos" statement?? 

[KGoodwin]

Thanks! Were you concerned when you bought them about their "no returns for halos" statement?? 

Moderately.  My scope config seemed to be similar to others who had not had halo issues, so I felt it would likely be OK.  Since it seemed halos were very setup dependent I figured I could either work it out or else resell them to someone with a different setup who wouldn't get the halos, worst case.  At the time I purchased them I was not willing to spend the amount it would take to get Chroma filters given the other large outlays I made for astronomy at the time.  This is definitely an issue with filters since the time you most need them is when buying a new, larger format camera and that frequently means you've just bought a scope that can accommodate that larger format sensor, and then maybe it required a new mount since it was a bigger scope...