Which OSC filters for a F2.8 lens - Forums

Topic starter

Jan 11, 2024

Hi AstroBinners!

i was putting together a rig around a zwo 6200mc pro ( or a 2600mc pro duo ) and a Nikon Otus 85mm lens. I intend to use it at F2.8

I was wondering which filters shud i go with for my 5 way EFW. I intend to populate my 5 way EFW as follows

1. IDAS HeUIB - already have from earlier
2. Optolong L-Quad Enhance or open to suggestions
3. Antilia Ha/Oiii or Askar Ha /Oiii or open to suggestions
4. Antila Hb/Sii or Askar Sii/Oiii or open to suggestions
5. Blackout filter for darks / open to suggestions

But my concern before i put out my money for either of these is if either brand will exhibit halos at F2.8 ?

Comments and views of all flavours invited…

Thanks in advance for your time, a happy new year and 366 days of clear skies

best

vikas chander

andrea tasselli

Frequent contributor

Jan 11, 2024

I'd use that lens at f/1.4 if with APS-C size and maybe f/2 with a full frame sensor, otherwise what's the point. The optolon seems pretty close to the L-Pro in performance so I guess it should not have signficant haloes (but also depends on the lens propensity to flare). Between the Askar and the Antlia I'd opt for the Antlia as I had few issues with modest haloes with the Duos. You don't need a black-out filter unless you operate remotely.

Helpful Concise

Pierre Konzelmann

Jan 11, 2024

You might want to check out Luke's Youtube channel, he's using a RASA scope (~f/2) with OSC cameras and has been testing a few dual narrowband filters, especially how they handle halos:

Player One Anti Halo Pro > The BEST New Duo-Narrowband Filter for OSC? Player One Anti-Halo Pro (youtube.com)
Optolong L-Extreme F/2 > Optolong Listened! - L-Extreme F2 Edition! (youtube.com) / The BEST Filter for F2?! Optolong L-Extreme F2 Edition! (youtube.com)
Antlia ALP-T 5nm High Speed > Watch BEFORE Buying THIS Filter!! Antlia ALP-T 5nm HighSpeed (youtube.com)

The Player One works best at f/3.6, per their website, so you'd be losing some photons due to bandwidth shift. Same applies to the Askar, I believe.

Helpful

Tareq Abdulla

Jan 31, 2024

I have also lenses that fast, in the past i also keep thinking about which filter to buy, now i found the answer that others don't like or follow and i can use it at wide open speed too without stopping down at all.

Manuel Peitsch

Feb 1, 2024

Hi Vikas,

I my experience the two Askar filters you mention (Ha /Oiii and Sii/Oiii) perform very well at f/2.8.
Cheers
Manuel

Tom Boyd

Feb 1, 2024

Manuel Peitsch:
Hi Vikas,

I my experience the two Askar filters you mention (Ha /Oiii and Sii/Oiii) perform very well at f/2.8.
Cheers
Manuel

That’s great to know. Currently use the D1 and D2 with my FLT132 and GT81, and am contemplating the new Pleiades 68 that I recall is a F3.8 and was wondering if the filters would work…