Astronomik 1.25" NB filters and What is MFR?

[TheButcher]

Hey all,

I am currious, I bought 2 Astronomik 1.25" filters Ha 6nm and O III 6nm. Now they did not mention the word MFR on the site or package. I then purchased an S II MFR 6nm from another online place that is respected. I did a little reading https://www.astronomik.com/en/fotografi ... ilter.html and I am curious if the first 2 filters are MFR or does it matter or just a marketing thing? I have the Ha and O III with no mention of MFR and bought it from a respected online vendor as well and they have the latest stuff usually.

I am just concerned that the 2 filters that I already got have the MFR coating as it says in the Astronomik site. Also does it matter? Should I return the non MFR's?

Thanks all

[JayTee]

I believe it stands for Most Focal Ratios. According to the OPT website.

Special Coatings Allow Filter Use Across Most Focal Ratios

Cheers,
JT

[TheButcher]

Thanks JT,

I wonder if it would make a difference using the one MFR with the two that are not MFR as far as focusing? I think their both 1mm thick.

[TheButcher]

Update:

I actually just read on the other vender that I got the O III 6Nm and Ha 6Nm, the O III was the MFR, it was written at the bottom but not as the name of the filter. And for some reason the Ha 6nm on both sites do not mention the MFR, but the main Astronomik site says it has it in MFR. I guess, the sites just didn't update it yet.

I was concerned because Astronomik's main site said "Our new filters are made in a completely new construction, which makes the best Out-of-Band blocking possible across the whole range of wavelengths from the UV up to IR! Your advantage of our new design is a extremly high contrast, minimized stray light, no halos and needle-sharp stars. With the new Astronomik MFR Narrowband-Emissionline filters you get data with the best quality possible: The best starting material to be processed to a awesome final image!"

I feel better now