When is light pollution so bad you might as well give AP up?

[garymck]

Hi,

Is there a point where light pollution/conditions are so bad hat you might as well give up imaging?

Last night I imaged for the first time in ages (health issues - heart - bypass surgery is NOT pleasant, but the alternative is worse). I live in Geelong West, about 1 km from the centre of the city. My imaging direction is limited to a bit of South, North and East (so directly over the city). My skies are Bortle 7, orange/red zone depending on which map you look at. In addition a high percentage of nights lose transparency due to a high mist that seems to come in sometime after 11pm.

My experience last night was frustrating - crap pictures that got massively worse when the mist came in after midnight. This was with my ASI071MC Pro. Yes I know one shot color is least suited to this imaging scenario, but I love the camera.

Under these conditions would it be worth doing narrow band? - I still have my QHY9/filterwheel with a full set of Baader filters (cant afford Astrodons - especially at the current exchange rate). The lack of transparency due to mist would affect narrow band just as much as OSC? I haven't done narrow band in the past as the number of "clear" nights here is so low that I figured I'd never get enough data to make it worthwhile - have gone up to 6-8 weeks between nominally clear nights that were not subject to a full moon! I could imagine that almost any target under these circumstances would become a multi year project!

Feeling frustrated enough to pack it in. Any suggestions? I think, if I didn't have so much money invested in equipment, I probably would chuck it in...Moving house is not an option...

not cheers :(
Gary

[multiweb]

I'm in the same LP zone. Ha with your QHY9 will be ok. So is Sii. Oiii will depend on the moon and needs to be shot at the zenith. You'll get gradients though. IR is good value any time. Color... well forget OSC. Too hard to process and color balance. Filter wheel + mono? Never tried, but I suspect it would be easier because you can capture the colors separately and have different integration times and subs length. Also need quality optics with minimum light scattering, well baffled and flocked to minimise stray light and reflections to increase contrast. Still plenty to image under LP.

[Marke]

I am in suburban Sydney and while its not easy going LRGB is a lot better than OSC . Keep your exposures short and stack more . Narrow band is no problem at all its much easier again.
This was a mix of Ha LRGB so its easily possible if I can do it.

[Slawomir]

Hi Gary,

Sorry about your frustration with astrophotography. I second what Marc recommended - maybe for a start just get on Ha filter - 5nm or 6nm if you can and go from there. Ha signal is usually (always?) the strongest for emission nebulae so such filter will certainly help to get better SNR more quickly and should make astro imaging rewarding again.

Speaking of light pollution, I doubt many astro-imagers had it worse than me (please check the attachment). However, relatively sucesfull narrowband imaging is possible from a light polluted area, such as from within a few km from a CBD: http://www.abc.net.au/news/2018-05-23/stargazing-live-photographer-dazzles-with-nebula-image-from-city/9783842

Having said that, since we have moved out of the city, I'm loving darker (but still humid and often cloudy) skies in a small town in NQ :)

[LewisM]

Gary, I keep persevering. Of course imaging is possible. I found though that my "saviour" was PixInsight which so adequately deals with the LP issues. All my imaging is 10 minute subs.

Here is my LP map. Home is circled in red near the airport. Note this changes when the airport is active, QUITE significantly!

[glend]

Narrowband works just about everywhere, and many prefer it.

[garymck]

Hi,
thanks for the encouragement, however, it's not just the light pollution I have to deal with - it's the damn high mist that comes in around 11-12pm most nights - summer and winter. It reduces transparency and exaggerates the light pollution. The light seems to reflect off the high mist making the LP worse than it actually is. Last night there were no clouds, but I could only see eleven stars!!! I'm not sure that narrow band can cut through this - but I will swap cameras and try it as a last resort.
cheers
Gary

[pjphilli]

My location also has bad light pollution. In recent years I have been complaining out its rapid increase - could lately only eyeball three stars in the Southern Cross. Recently had both my eyes lenses replaced owing to cataract problems. The lens are set for long focus. Wow - I can now easily see mag 5 stars and less and of course all the Cross stars. The stars are now in pinpoint focus instead of slightly blurry. Enthusiasm for astro imaging restored! Peter

[multiweb]

Transparency will make LP worse but if you had the same conditions under dark skies you'd have bloated stars and loss of details as well. Can't do much about humidity in the air, but it looks like we're heading for a dry hot summer so I wouldn't worry too much.

[Martin Pugh]

Hi Gary
I have certainly lived with severe LP in the past, particularly when I lived in Omaha and (very near) Lisbon. It sucks but I hope you are recovering well from your surgery.

One solution that could be open to you is to go remote; a service I offer here in rural NSW (https://www.martinpughastrophotography.spac e/remote-imaging-and-telescope-hosting). I have a chap who lives in Sydney who now images from my place (also an IIS resident PRejto). If that is not an option, then data subscription would be another consideration. This completely takes the pain away, and you get to process high quality data taken with high end equipment under very good skies.

cheers
Martin

[glend]

I suspect this post violates the TOS section that applies to vendors and advertising. :shrug:

[leon]

:shrug:

Leon