Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

New Baader CMOS filters (?)

  • Please log in to reply
13 replies to this topic

#1 AstroCatinfo

AstroCatinfo

    Messenger

  • *****
  • topic starter
  • Posts: 465
  • Joined: 22 Jan 2016
  • Loc: Prades, Catalunya - Spain

Posted 12 May 2021 - 09:02 PM

I have seen that Baader is realising a new brand of filters specially designed for CMOS cameras. Anyone has been able to test it?

 

My previous experience with Baader filters is a bit disapponting due to halos in the G,B,OIII filters.

 

Is this new realese a branding strategy? Or there is a clear improvement?

 

https://www.teleskop...ed-Filter.html 

 

Thanks for your feedback,

 

Aleix



#2 Jon Rista

Jon Rista

    ISS

  • *****
  • Posts: 24,854
  • Joined: 10 Jan 2014
  • Loc: Colorado

Posted 12 May 2021 - 10:09 PM

 

 

♦ Reflection blocker coating against reflections in combination with correctors placed near the filter

♦ Exact and narrow half-widths for optimal signal-to-noise performance

♦ Identical filter thicknesses for homofocality

♦ Blackened edges

♦ The front side is marked in the form of a black outer rim

To me, these seem to be optimizations targeting mitigation or elimination of microlens diffraction artifacts. Antireflection features, clearly marked front side, blackened edges...these are things that people on these forums have been talking about in particular in recent months, especially with regards to the IMX455 and its occasional microlens diffraction issues. I am not sure if both sides of the filters are AR coated...I've heard that for interference filters (i.e. NB) that's not possible...but this does say the reflection blocker coating is for use in combination with correctors. A bright star could easily enough cause reflections off of multiple surfaces as microlens-diffracted light bounces off the sensor back up the optical path...the sensor coverslip (both sides), the sensor window in the camera (both sides), the filter (both sides), and any corrective optics. 

 

I think that it is more important to have the anti-reflective side of the filter facing the sensor. Otherwise, the more reflective side can and will (and DOES) reflect those microlens grid patterns back to the sensor. The fact that this here states the reflection blocker should face any corrective optics makes me wonder about how optimal they really are for CMOS sensors, but I guess someone will just have to test them out and see. 

 

Anti-reflective properties are clearly a critically important part of the design of CMOS cameras. The sensor cover slips, the sensor windows in the camera bodies, and the sensor-facing side of filters, should all be coated in high quality multi-layer anti-reflective coatings to minimize or eliminate microlens diffraction, IMO. 


Edited by Jon Rista, 12 May 2021 - 10:10 PM.

  • AstroCatinfo likes this

#3 TareqPhoto

TareqPhoto

    Fly Me to the Moon

  • -----
  • Posts: 7,069
  • Joined: 20 Feb 2017
  • Loc: Ajman - UAE

Posted 12 May 2021 - 10:50 PM

No mention for LRGB filters?!!! frown.gif



#4 PiotrM

PiotrM

    Soyuz

  • *****
  • Posts: 3,985
  • Joined: 03 Jan 2010
  • Loc: Poland

Posted 13 May 2021 - 03:19 AM

No mention for LRGB filters?!!! frown.gif

Wide bandpass filters don't suffer form the same problems as very narrow bandpass filters. Light cone from fast telescopes/lenses hitting the filter at their stepper angle causes that the coating to have slightly different characteristics for them so instead of passing H-alpha the filter passes wavelengths few nm higher or lower. Plus anti reflection features which are quite common for RGB filters as they operate with "more light".



#5 TareqPhoto

TareqPhoto

    Fly Me to the Moon

  • -----
  • Posts: 7,069
  • Joined: 20 Feb 2017
  • Loc: Ajman - UAE

Posted 13 May 2021 - 04:35 AM

Wide bandpass filters don't suffer form the same problems as very narrow bandpass filters. Light cone from fast telescopes/lenses hitting the filter at their stepper angle causes that the coating to have slightly different characteristics for them so instead of passing H-alpha the filter passes wavelengths few nm higher or lower. Plus anti reflection features which are quite common for RGB filters as they operate with "more light".

But it is not about fast speed scopes only, if you look at the link you will see filters as 6.5nm and 4nm, not interested in any of those, but it is about reflection block or halo managing, LRGB filters have more damage to halo than NB filters, so i was hoping that Baader is bringing maybe new LRGB filters better for imaging similar to AD/Chroma and Astronomik.



#6 freestar8n

freestar8n

    Vendor - MetaGuide

  • *****
  • Vendors
  • Posts: 10,522
  • Joined: 12 Oct 2007
  • Loc: Melbourne, Australia

Posted 13 May 2021 - 05:15 AM

Halos are due to the filters - and they can be narrow or wide band.  And cmos doesn't play a role.

 

The weird grid pattern of spots is just due to the sensor itself - and also happen with narrow or wide band.  And it mostly happens strongly with recent cmos sensors.

 

If they have improved the AR coatings that will help with halos - but I don't see it helping with the grid patterns or anything specific to cmos.

 

Frank



#7 PiotrM

PiotrM

    Soyuz

  • *****
  • Posts: 3,985
  • Joined: 03 Jan 2010
  • Loc: Poland

Posted 13 May 2021 - 11:58 AM

But it is not about fast speed scopes only, if you look at the link you will see filters as 6.5nm and 4nm, not interested in any of those, but it is about reflection block or halo managing, LRGB filters have more damage to halo than NB filters, so i was hoping that Baader is bringing maybe new LRGB filters better for imaging similar to AD/Chroma and Astronomik.

LRGB is IMHO more contested than narrowband. There is Astrodon with multiple sets and overall there are multiple takes on what band RGB filters should pass. Baader is pure astro company and they aren't as agile in opening new products like say Chroma or some Chinese brands that have the backing of a parent company that does interference filters for wider, non-astro market. I would say that if there will be room for improvements and the margins will be good Baader will release newer RGB set and if not then there is very little reason to releasing same product as competition while being late. I would much more like to see them releasing helium or neutral oxygen narrowband filters or Lunar petrographic filter set - something that isn't directly on the astro market.



#8 TareqPhoto

TareqPhoto

    Fly Me to the Moon

  • -----
  • Posts: 7,069
  • Joined: 20 Feb 2017
  • Loc: Ajman - UAE

Posted 13 May 2021 - 03:22 PM

LRGB is IMHO more contested than narrowband. There is Astrodon with multiple sets and overall there are multiple takes on what band RGB filters should pass. Baader is pure astro company and they aren't as agile in opening new products like say Chroma or some Chinese brands that have the backing of a parent company that does interference filters for wider, non-astro market. I would say that if there will be room for improvements and the margins will be good Baader will release newer RGB set and if not then there is very little reason to releasing same product as competition while being late. I would much more like to see them releasing helium or neutral oxygen narrowband filters or Lunar petrographic filter set - something that isn't directly on the astro market.

I have no objection of any manufacturer to produce whatever they like as long there are buyers or people getting interest and it do the job, SVBONY having many items and products around and i don't see them to be recommended and loved as for example Skywatcher or Orion or even Baader in term of filters, so i know Baader high quality items, but their RGB are like 50 50, some people swear by them and others just giving up, i have their IR Pass or IR range filters and other filters such as LP and moon/skyglow and Contrast Booster, happy with them so far, but when coming to NB and RGB then this is another story.

 

The topic here is about a new CMOS filters, so i thought maybe they made a better quality or performance filters of LRGB and NB, i will choose Antlia Ha 3.5nm or even 3nm over Baader Ha 3.5nm, that is something i can't help but to ask why Antlia a new gamer did that while Baader in the game since very long time are still not trying something better? Don't get me wrong, i respect Baader, but i am an open free customer, not forced for one brand like Baader if there are a better products either more expensive like AD/Chroma or cheaper like Antlia, and i see few more manufacturers are trying to get into this game and one day maybe Baader if they didn't do anything then they won't be any better recommendations than others anyway in term of quality and price.



#9 PiotrM

PiotrM

    Soyuz

  • *****
  • Posts: 3,985
  • Joined: 03 Jan 2010
  • Loc: Poland

Posted 13 May 2021 - 03:39 PM

 i will choose Antlia Ha 3.5nm or even 3nm over Baader Ha 3.5nm,

Super narrow H-alpha has it limitations and it has most of it uses for H II nebulosity regions. For anything aside of that (planetary nebula, supernova remnants, wolf rayet star nebula etc) you would benefit from 6-8nm H-alpha filter to also catch all of [N-II] emission - which can be stronger than hydrogen emission. Super narrow H-alpha filters existed for years (Astrodon) yet for good reasons it wasn't the most popular product on the market.

 

Those new filters from Baader and other can see use with super-small-pixel CMOS sensors + lenses for widefield imaging of those H II nebulosity regions - and majority of lenses will be fast like f/2-f/4 so a matched filter is really important for optimal results. But also a f/3.4 to f/1.8 new Baader filter should not be used with slow scopes.
 



#10 TareqPhoto

TareqPhoto

    Fly Me to the Moon

  • -----
  • Posts: 7,069
  • Joined: 20 Feb 2017
  • Loc: Ajman - UAE

Posted 13 May 2021 - 03:45 PM

Super narrow H-alpha has it limitations and it has most of it uses for H II nebulosity regions. For anything aside of that (planetary nebula, supernova remnants, wolf rayet star nebula etc) you would benefit from 6-8nm H-alpha filter to also catch all of [N-II] emission - which can be stronger than hydrogen emission. Super narrow H-alpha filters existed for years (Astrodon) yet for good reasons it wasn't the most popular product on the market.

 

Those new filters from Baader and other can see use with super-small-pixel CMOS sensors + lenses for widefield imaging of those H II nebulosity regions - and majority of lenses will be fast like f/2-f/4 so a matched filter is really important for optimal results. But also a f/3.4 to f/1.8 new Baader filter should not be used with slow scopes.
 

That is something i will chooe from Baader for my lenses from F1.4 or even F/1.2, but for my scopes if i want super Ha filter then i don't think i will chose Baader, i have Astrodon Ha 5nm for that reason you meantioned, to capture something of NII, in fact in 2017 i was asking about which version of Ha to buy, 3nm or 5nm, and that time people here of CN just told me if i want to catch something of NII signal then 5nm is the choice, and i did, and i am SUPER happy with the filter really, but not all targets i want to do with Ha 5nm only, and not all targets will have that NII anyway, so sometimes i want to just go with pure Ha without more signals or say much narrower Ha, and this where Ha 3nm is in my plan, next to my Ha 5nm, i was thinking about Baader Ha 3.5nm last 2 years, but something in my heart told me to NOT go with that and just wait, i did and i saw another option better.



#11 TareqPhoto

TareqPhoto

    Fly Me to the Moon

  • -----
  • Posts: 7,069
  • Joined: 20 Feb 2017
  • Loc: Ajman - UAE

Posted 13 May 2021 - 03:53 PM

Look at OP post, 

 

"My previous experience with Baader filters is a bit disapponting due to halos in the G,B,OIII filters."

 

This is likely the most issues we are facing, and we are like forced to go to AD/Chroma to solve it, means to pay more, but it depends on different factors also, i mean i saw results done with LRGB not AD/Chroma and the B/G signal were just great, i did buy Chroma OIII anyway as i know i wanted 3nm, i got good price for that filter, but how many will buy that anyway? And why Baader making this 4nm OIII is it didn't fix something but only to give stronger signal or contrast? I still don't know if i should replace my Optolong OIII 6.5nm to Baader OIII 4nm, if they can make a new OIII 4nm or 3nm that is better resisting halo even only slight i will be interested in that, but not in rush because i already have OIII 3nm, but i don't have Ha 3nm, and only Antlia is in my list for price, the filter results are very promising everywhere i see, Baader Ha 4nm isn't bad as well, but if i have to choose then i will go with Antlia, and if it is OIII then definitely i will not go with Baader while Antlia isn't good yet but they are doing good to fix it somehow.


  • AstroCatinfo likes this

#12 PiotrM

PiotrM

    Soyuz

  • *****
  • Posts: 3,985
  • Joined: 03 Jan 2010
  • Loc: Poland

Posted 13 May 2021 - 03:59 PM

Look at OP post, 

 

"My previous experience with Baader filters is a bit disapponting due to halos in the G,B,OIII filters."

 

This is likely the most issues we are facing, and we are like forced to go to AD/Chroma to solve it,

 

Oh, poor you, you need 1000 filters to solve reflections problems. The thing is reflections are VERY SPECIFIC to given setup. Some find Baader good, some have to use Astrodon, or Astronomik or Optolong/Chroma... There is no universal answer to which filter will not have reflection or halos.

 

 

I still don't know if i should replace my Optolong OIII 6.5nm to Baader OIII 4nm,... but not in rush because i already have OIII 3nm

Fix your imaging chain first, then start imaging, you already have more filters than needed.

 

that is better resisting halo even only slight i will be interested in that

do you even have "halos" ? Or do you just want to go on next shopping frenzy?



#13 TareqPhoto

TareqPhoto

    Fly Me to the Moon

  • -----
  • Posts: 7,069
  • Joined: 20 Feb 2017
  • Loc: Ajman - UAE

Posted 13 May 2021 - 04:31 PM

Oh, poor you, you need 1000 filters to solve reflections problems. The thing is reflections are VERY SPECIFIC to given setup. Some find Baader good, some have to use Astrodon, or Astronomik or Optolong/Chroma... There is no universal answer to which filter will not have reflection or halos.

 

No need 1000 filters, at least not filters that cost thousands as many did here.
Some find and some didn't find, so it is subjective and not a fact? Or it is not the filter fault?!!!

 

Fix your imaging chain first, then start imaging, you already have more filters than needed.

 

Fixing with more items of course, and no i don't have, but i need few more and i am done.

 

do you even have "halos" ? Or do you just want to go on next shopping frenzy?

 

Shopping isn't a bad idea, as long i know what to shop for, i see others shopping forever and no one is talking, anyway, i already mentioned in 2018 and 2019 that two years later which is 2020 and 2021 will be my shopping years, so did 2021 finished already?!!!

Read above ^^^



#14 AstroCatinfo

AstroCatinfo

    Messenger

  • *****
  • topic starter
  • Posts: 465
  • Joined: 22 Jan 2016
  • Loc: Prades, Catalunya - Spain

Posted 15 May 2021 - 09:22 AM

For my new setup I already have the LRGB 36mm Astrodon kit. I will be used on:

 

Sigma Art 85mm + ASI2600MM Pro + EFW7pos

 

I'll also add a Antlia 3nm Ha. Don't know if it will work properly. Iwill close the lens apperture to at least f/3.2 (originally at 1.8).




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics