I thought this thread on CloudyNights was worth posting. for those interested in NB filters and considering Optolong:
https://www.cloudynights.com/topic/602155-testing-optolong-and-baader-narrow-band-ha-sii-filter/ (https://www.cloudynights.com/topic/602155-testing-optolong-and-baader-narrow-band-ha-sii-filter/)
It makes an interesting read.
Robert
Interesting read, I have never before heard of Optolong filters, all mine are Baader.
Carole
I remember that thread well. It's certainly one that will live in the memory! It has most of the essential ingredients for a really entertaining thread.
I really love the poorly designed experiment that anyone can do at home :cheesy:
This is an essential part of the fun because absolutely everyone can get involved and give their opinion :twisted:
The experimental design means you can't tell out-of-band sensitivity of the filter from out-of-band leakage from the screen's RGB emissions with the result that even Astrodon filters end up getting flak!
Unfortunately an expert enters the discussion and they actually listen to him. The very best threads are those where the only person bringing sense to the conversation gets shot down in flames and ignored.
Astro-forums - you gotta love 'em :boom:
Mark
P.S. I really want a proper spectrometer.