Astronomik 6nm, what has been your experience?

Hi Paolo,

for a longer time I used cheap(ish) filters. After a lot of problems with halos, I invested (after a long period of doubts) in an Astronomik Ha 6nm filter. It was really amazing. For some time I had to pair it with Optolong SII and OIII filters (6.5nm). I always had some halos from the Optolong filters while the quality of the images taken with the Astronomik was really good. Some weeks ago, I was finally able to buy the SII and OIII from Astronomik as well and after some tries, I was really satisfied by the quality of the now matching filters. In my opinion, they are really good.

I used the filters on my Quadruplet APO 350mm/f5 as well. I had no signs of halos with it. I also used them with my 8" f/4 Newton without problems. These filters are really expensive, and while I miss the money I paid for them, I really enjoy the images now.

From my point of view, I would suggest those filters, if you are able to buy the complete set.

I hope this helps

Christian

Oh..., I forgot to include the example images.

This is the combination Astronomik/Optolong

https://www.astrobin.com/b3y54d/

and this with only the Astronomik filters

https://www.astrobin.com/efdu9n/

Have a look at the brighter stars and you will notice the difference. It is not huge

CS

Christian

I have started using the 2" Atronomik MaxFR 6nm Ha and WII with  FSQ106ED at F5. I do 10min. Exposures with a Starlight Xpress Trius SX46. It uses the KAF 12600 chip (6nm pix).  There were NO halos. Earlier,  I had tried a older 12nm Ha from around 2008 with this camera/scope and there were substantial halos.

I have been doing narrow band with the Astrodon 1.25 5nm Ha, 5nm SII and 3nm OIII., With the  Fsq106ed at F3.64.  No halos at all with those filters. But, like you, moveing to the 2" Astrodons were too pricy. I also image in Bottle 7 skies.

I also uses a 2" Chroma 3nm OIII for F3 systems or above. I got a very good price on it at $775, new. It had considerable dust and water stains. They cleaned off, but disappointing for new. I have read of similar experiences. Not to mention for the price you only get a small paper envelope to stor in.  The Astronomics come with a flexable plastic case.

I fave discovered that in Bortle 7 skies, a 3nm OIII really smooths out the noisy background usualy associated with OIII.  And Astronomiks does not make the MaxFR narrower that 6nm. I have never gone narrower that 5nm with Ha or SII. The Ha is more abundant and usually renders good S/N.  Like the OIII the SII can be noisy.

Note. I had to wait a month or so for the Astronomik Ha and SII  from OPT. The OIII came about a month later, but I cancelled  it , because I had receive the Chroma OIII.

I do not have the image I'm working on (Elephant Trunk, IC1396) completed to show. I'm still  gethering data.

Lynn K.

Paolo:
Thank you both guys for your feedback, really appreciated!

@Olly Barrett : I'm curious, why did you go with Optolong for OIII?

 

Paolo:
Thank you both guys for your feedback, really appreciated!

@Olly Barrett : I'm curious, why did you go with Optolong for OIII? Was the Astronomik bad?

I went Optolong for the Oiii purely because people with the same image train as me had said (in many different blogs) that it worked great and it does. To be honest Oiii was my biggest issue for halos and this was the perfect solution👍🏻

I use these filters because they're specifically not supposed to produce halos.  Astronomik made this a selling point, and I haven't seen any halos in either the HA, SII, or O3 filters. I believe these are well worth the money.  If a halo is present, I believe Astronomik has a process where they will review your images and then replace the filter at no cost.

I do have Astronomics Ha 12 nm. filter - no halo in both APO and ACF, good quality. Thinking about 6 nm.Ha….🤔

Lots of valuable feedback guys, thanks a lot!
It's very likely that I'll go with those  considering all these positive comments.
My only doubt is the 6nm bandpass for the O3, but I think I can start with this for now and, maybe, sell it if I see the need to go narrower.

Lynn K:
Keep in mind that the F ratio greatly effect the halos. Using the older Astronomik 12nm at F7 of 5.6 on a refractor didn,t cause much halos,. But, I also did Hyperstar mono filtered F2 imaging and that caused very bad halos.  The F ratio also effect the filters ability to be parfocal.  I have found that even Astrodons are not parfocal at F3.64.  And of course the filter ability to maintain  transmission with steep light cones caused by low F stop optics.

I am encouraged to see that Maciej is using the Astronomiks with the F3 Officina Stallare RH200. That is the scope I plan to use them with. Consiquintly, why I went with the MaxFR version good to F2.2.  I have not had a chance to use them with that scope yet, because the scope is in Italy for repairs since June. Very slow service.  As I mentioned above, I went with the Chroma for the OIII 3nm. It is good to F3.

Lynn K.

If you buy an ASHA 6 nm Astronomik filter, for example from Teleskop-Service, you can specify the brightness range (f) of the lens for which you want to use it and then it is appropriately selected. Mine is f2.2 up to f8.
CS Maciej

Considering an upgrade.. currently using the Optolong narrowband set.
On most targets, I have no issue. But on some targets with a very bright star, I can get a bit of a halo in some of the filters. 

Either way, looking at the Astronomik series. Does anyone have a clear idea on the difference between the "normal" and the "MaxFR"?
They're listed for 70 euro more, each. Which is significant enough, as you need 3 of the darn things.

It would appear that the MaxFR is used for "fast" scopes. Mine is an Esprit 80ED, at F5.0.
So pretty fast, but not quite RASA levels, so would my scope even benefit from the additional 70 euro per filter, if that is the main selling point of the MaxFR? or are the normal ones "enough"

Hi Steven. The difference between the different Astronomik filters is their ability to maintain high percentage of wave length  transmission to the whole and edge of the filter. Most filters will transmit well in the center of the filter, but with a low F ratio  steep angled light cone, the filter can suffer light transmission at the edge.  This means that the image will be contrasty (s/n) in the center part, but will have poor data/signal towards the edge. 

The faster the scope (smaller F ratio) the steeper th light cone angle and the worst the problem of wave length transmission. THIS ONLY APPLIES TO NARROW BAND FILTERS.

Astronomik standard (forget the technical name) has good transmission to F 4 with the 6nm. I am pretty sure about that, but check the web site. You can go to a lower F ratio with the 12nm, which is OK if you are in a Dark sky and not  fighting light pollution. 

The Astronomik MaxFR filters are designed to accommodate very fast scopes such as Hyperstar and RASA. The 6nm is good to F 2.2.  I will be using it at F 5, which is really not needed, but also at F3, which I will need.

Imaging F 5 should not require the MaxFR version. The Astronomik web site explains this very well. It is best to to refer to it.

Baader came out with the 1st narrow band filters for fast scopes. They were called Fast F2. There have been many reviews claiming they produce star halos, especially with OIII. 
OIII always lets in more star light and consiquintly worst star holos.

Lynn K.