Hi all!What Ha and OIII filters would you recomment (10" f4 Newton with QHY294M)? I need some for the my new Ultra-Slim-Filterwheel from QHY, that means not thicker than 5mm (without thread).I am aware that Antlia, Chroma and Astronomik are kind of best in class, but you may have other brands in use, too?ThanksMike
What Ha and OIII filters?
Hi Mike,
I highly recommend the Baader Ha 7nm. It's a very good filter for its price, no halos and provides always a sharp image.
I don't recommend the Baader OIII at 8.5 nm. Halos on stars and background gradients are quite common with it. I think I will replace it with the OIII Optolong at 6.5 nm since I've heard good things about it.
Hope it helps in your choice.
Clear Skies,
Andrea
I highly recommend the Baader Ha 7nm. It's a very good filter for its price, no halos and provides always a sharp image.
I don't recommend the Baader OIII at 8.5 nm. Halos on stars and background gradients are quite common with it. I think I will replace it with the OIII Optolong at 6.5 nm since I've heard good things about it.
Hope it helps in your choice.
Clear Skies,
Andrea
Well Written Helpful Concise Supportive
I highly recommend the Baader Ha 7nm. It's a very good filter for its price, no halos and provides always a sharp image.
I don't recommend the Baader OIII at 8.5 nm. Halos on stars and background gradients are quite common with it. I think I will replace it with the OIII Optolong at 6.5 nm since I've heard good things about it.
Yeah, the Optolongs are interesting. I will take a closer look but it seems that there are not that common in use ;-)
The Baader is too thick with 7mm without thread, I guess.
CS
Mike
I highly recommend the Baader Ha 7nm. It's a very good filter for its price, no halos and provides always a sharp image.
I don't recommend the Baader OIII at 8.5 nm. Halos on stars and background gradients are quite common with it. I think I will replace it with the OIII Optolong at 6.5 nm since I've heard good things about it.
Yeah, the Optolongs are interesting. I will take a closer look but it seems that there are not that common in use ;-)
The Baader is too thick with 7mm without thread, I guess.
CS
Mike
7nm, It's the Half Bandwidth. Unless you mean the thickness of the frame holding the filter... that I don't know. Anyway, the Baader is 2mm thick as well as the Optolong...
Yes, the whole filter. It seems they are too thick for my FW.
Yes, the whole filter. It seems they are too thick for my FW.
I was looking at the different models of the Ultra Slim FW from QHY, all seem to support unmounted filters. If your supports it too it would be the way to go in my opinion with such a thin FW.
The Astronomik 6nm are very good. If you are planning to go faster than f4 later on, you may want to consider the MaxRF. I have the 3 filter and they don’t show halos. They are 1mm ticker
Hi Mike, you do know that the numbers above are not the thickness of the filter itself right? These are the filter bandwidths in nm.
Correct, I am not talking about the bandwith, but the measures of the filter as a whole ;-)
How about the Zwo 3 nm filters ? Have anyone used them? And what are the bandwidths of those duoband (zwo) or Optolong Lenhance/Lpro/Lextreme filters?
Per the information at Opt:
https://optcorp.com/products/optolong-l-enhance-filter-2?gclid=CjwKCAjwx6WDBhBQEiwA_dP8rROkW-G1uL8rAG1YXXkSchfxfLnJa66SN0Ob5A1zfCfjCGs5vkQB7xoCbfsQAvD_BwEL-eNhance Filter Spectrum CurveThe bandwidths:= 24 nm for OIII and H-beta= 10 nm for Ha
The L-Pro is intended more for broadband targets and has very wide bandpasses.
The L-eXtreme cuts out the H-beta and just has the OIII in one band and Ha in the other. It's listed as 7 nm in some information I see.
The graphs of all three are in the link I listed. I have the L-Pro and L-eNhance, and I can get pretty nice images of emission nebulas even with a stock DSLR. I've been pretty happy with them.
I don't know about the ZWO, but I ordered their 7nm LRGB and narrowband as part of a camera kit, so I will learn about them whenever I get the kit.