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View Full Version here: : Which light pollution filter?


JtPhotographer
01-05-2018, 05:12 PM
I'm after a light pollution filter that matches the quality of my professional camera + lenses.
Are the NiSi as advertised on ebay any good? Or the Chinese made Haida ? Or the Orion ? or anything else. Prefer a square 100 x 100 mm one , but a 77 or 82 mm one will do.

I need it in the Warrumbungle N.P. to shoot the Milky Way. Yes its a Dark Sky Park but still the light pollution from Sydney et all glares even here a little.

JA
01-05-2018, 11:44 PM
Hello JT,

I've not used either of those filters and there is no spectral transmission data for either filter in the ebay advert so it's hard to comment, beyond that I think that they're probably no more than a neodymium or didymium type filter which blocks some light pollution bands, but typicallly nowhere near as much as the typical astronomic broadband light pollution filters which don't seem to be available in those (photographic lens) filter sizes.

Something which might help, which I have tried is a Hoya Red Intensifier (Red Enhancer) Filter or stronger still a Marumi Redhancer filter. They are both quality filters, but i prefer the Marumi. I've attached the filter curve for the Hoya Red Intensifier and a link below. Tiffen and Crystal optics are also quality brands that make these filters.

The Marumi is much better at removing the light pollution and extracting the stars - see composite image below chosen because of the challenging lighting: made at full moon, with street lighting illuminating the treetop 20m away as well as other general lighting. I don't recall exposure I used maybe 30s f/2.8 on a 24mm Nikkor. Left to right In the Image: NO FILTER, HOYA and then MARUMI


https://www.lonelyspeck.com/hoya-intensifier-review-an-affordable-light-pollution-filter-for-astrophotography/

BTW I know you've opted for screw on 77 and 82 or 100mm square types, but what about a clip in filter? - The type that clips in to the camera body between the sensor and lens. Is your camera a candidate for that?

Best
JA

leon
02-05-2018, 06:50 AM
Hi Jacob, out of the ones you have mentioned in your post, i think the Orion would be a good choice.

However if you want a really good filter although a little expensive i have used these and they have proven to be excellent.

Leon

http://www.sciencecenter.net/hutech/prices/filters.htm

JtPhotographer
02-05-2018, 08:46 AM
Hi JA , thanks for the info.
It looks quite what I'm after !
Still so much to learn for an old photographer but a baby when it comes to Astro Photo :-)
I also received a private message about optcorp.com filters:
Quote:
-- OPT has developed a TRIAD filter that is three (3) filters in one.
Ha + Hb + OIII the filter comes in 2 sizes both sizes are round and mounted 1.25" & 2" --
What do you think about that " 3 in one " ?

JtPhotographer
02-05-2018, 10:07 AM
Thanks Leon , I will look into that as well !

blink138
02-05-2018, 10:40 AM
jacob there was post recently on these filters which look extremely interesting
for widefield you can get them in 77mm and other adapters to step up or down

https://www.cyclopsoptics.com/filters/stc-astro-multispectra-filter/

LewisM
02-05-2018, 10:43 AM
None.

I live in HORRIBLE light pollution , and I tried all the LP filters out there - CLS, LPS, UHC, IDAS, STC and so on - some cheap, some VERY expensive.

I came to the conclusion by FAR the best result is to remove the LP in processing. BY FAR better. This is also mentioned on Cloudy Nights and other websites.

PixInsight does an incredible job neutralising LP, as do a few Photoshop plug ins.

kittenshark
03-05-2018, 12:33 PM
Bear in mind that newer LED lights, the full spectrum ones, can't be filtered out.

Better than nothing I suppose, as a fair few places still use sodium vapour lights.