I tested LIGHT POLLUTION SUPPRESSION FILTERS with a SPECTROMETER!

Thank you for an very unbiased review of light polution filters. Regarding baader neodymium, semi-apo and contrast booster, Svbony moon, optolong moon filters. These are of same type, with different cut-off. Horrible light pollution filters, should never had been promoted as such. To short up. They are brilliant visual planetary filters, to boost contrast. The non-cut version (neodymium can be combined with yellow optics/eyepieces to get a more natural color scheme. Semi-apo, is very good at Jupiter, when low in horizon, or using a not so compensated refractor. And contrast booster is the best Mars filter on the market. Combining sv-bony or optolong moon with written #8, is supposedly neutral, but gives a supposedly good boost on Jupiter or Mars.

good analysis, emphasizes that there is no substitute for a dark night sky. At times of high solar activity, like now, there could be significant green light from the 558 nm airglow. SDSS filters were designed to eliminate this band, with g' ending at 540 and r band beginning at 575

Very nice video! The - less scientific - test I did with my Astronomik CLS-CCD clip filter was to take a night picture of the neighborhood from my rooftop. While most of the lights were suppressed I could clearly see some bright projectors, I assume they are LED. This was few years ago, I will test again tonight.

Thanks for making this content. I own the Antlia RGB and IDAS LPS D1. It was nice to see how well they compare to each other. I'm surrounded by LED lights and to top it off a building across the street has a massive LED light at the top to illuminate the parking lot thus making a huge glow that spreads all over the place, very, very irresponsible. I love the Antlia RGB! has worked really well in my skies. Thanks again!

Very nice scientific study! It’s great to have such relevant data to complement qualitative descriptions and and marketing hype. The spectral analysis is a valuable addition to the fight against light pollution, especially when it is about a real, specific location rather than a general description.

Great work! I just picked up the Antlia RGB Ultra, looking forward to seeing how it fares in my Bortle 9.

As usual very interesting video. Fortunately, since a few month, because of rize of energy cost, more and more french town are turning lights off at night. I hope this good move will be kept in the futur even if energy price decrease. Bonnes vacances :-)

Excellent ! Hope your work inspires at least a few manufacturers to look into better products for immediate needs. And in about a few decades or so better lights for general public to use.

thank you

Super vidéo merci et un grand merci pour les sous titres en Français qui aide bien mais tu parle pas trop vite donc je m’en sort avec mon petit niveau en tout cas super et merci beaucoup passe de bonne vacances

Great video! Those dang broadband led lights. Hopefully we transition away from them at some point. CS!

The NPB has been praised in visual observation for a while now.

10:35 Unfortunately these narrow stopbands are not manufacturable/usable - due to angle-of-incidence sensitivity....

I like the idea of the new filter at the end, but i think the 405 violet notch is profligate. The line is relatively weak compared to other mercury lines, and mercury vapor lighting for general illumination is falling out of favor so rapidly now it'll barely exist in another decade. It will reject more useful light than it blocks nuisance light.

Bravo pour cette vidéo qui contient beaucoup d'informations super-intéressantes! Sur ma chaîne Youtube, j'ai aussi testé plusieurs filtres d'astro. Je suis curieux par rapport à votre méthode pour mesurer la réponse instrumentale de votre spectromètre, en intensité. Je l'ai fait sur le mien (Flame-S-VIS-ES de OceanInsight/Optics) en utilisant une ampoule de feux de voiture (non-halogène) et la réponse de mon système était encore plus non-linéaire que la vôtre! Merci encore de partager ainsi vos découvertes.

What is your neon-argon calibration lamp and where did you get it?

Sign me up for a DSG-LPS filter! Great post