I have a small cabin (currently somewhat dilapidated) very near my observatory that will soon be renovated and fitted out to be used for temporary and/or ongoing accommodation (not for me).
A number of light pollution mitigation solutions, like shielding, extended privacy screens and removing windows facing the observatory, as well as decent curtains on other windows, are all being planned in the design of the renovation and fit-out, to prevent/minimise detrimental effects on my observatory operations while the cabin is occupied at night.
Something I was looking for some advice on however, is the best type of readily available (Bunnings/Homehardware etc) LED or normal light bulbs/fittings that could be used in the cabin fit-out (both inside and outside lighting) that would best minimise any effects on the immediate local site light pollution, from an astronomical observations perspective, but still provide adequate amenity for the occupant? The cabin will be on a small to modest solar power system, likely running 240V via an inverter, so conserving energy will be desirable.
Thanks for any feedback
Mike
Last edited by strongmanmike; 19-10-2019 at 05:03 PM.
I'm thinking going with warm (towards red) colour lighting could be better as red colour is scattered less than blue, so warm light should be better in this regards than cold light.
I'm thinking going with warm (towards red) colour lighting could be better as red colour is scattered less than blue, so warm light should be better in this regards than cold light.
Yes good idea Suavi, I had thought of that, should incandescent bulbs be used, per current light sockets in the cabin. I was going to go 25W max too, as it is a small cabin and that wattage should be sufficient and conserve the batteries.
Wondering what the specifics are to look for if LED lighting were to be used..?
well there was a study that said orange lights are better for night vision, so can you get one of those led light bars that can produce many colours.... and disco disco......LOL. you can get 12v versions of those
well there was a study that said orange lights are better for night vision, so can you get one of those led light bars that can produce many colours.... and disco disco......LOL. you can get 12v versions of those
A number of light pollution mitigation solutions, like shielding, extended privacy screens and removing windows facing the observatory, as well as decent curtains on other windows, are all being planned in the design of the renovation and fit-out, to prevent/minimise detrimental effects on my observatory operations while the cabin is occupied at night.
Whilst more of a long term thing, planting a row of trees between your cabin and Obs may be a thought. All the things you listed are good, but I worry about the "curtains" bit - that requires co-operation (utilisation) from "tenants"
Picking a species of tree that is dense, and tall enough (but not too tall), may be a thing to offer 99% blockout.
If the cabin has low voltage DC, that makes it easy as you can wire up anything yourself, legally. (If it uses 240VAC for lighting, you're limited to certified products and need an electrician to do the wiring).
What you do depends on whether you want to protect unaided night vision or eliminate photographic effects.
For the former, try external shutters on the cabin windows.
For the latter, you could try selecting specific wavelengths of LEDs (I've seen plenty on Alibaba) and get a local electronics shop to solder them onto a backplane/project board/diffuser, and wire them up for you with a bias circuit (if you don't want to do it yourself).
Pick the LED wavelengths to fall into the blocked portions of your light pollution filters or simply outside the bands of your narrowband filters if that's all you're using.
I've been thinking about a project like this for some time - to try and produce astro-friendly LED street lighting - assuming we use light pollution filters in our back yards.
Whilst more of a long term thing, planting a row of trees between your cabin and Obs may be a thought. All the things you listed are good, but I worry about the "curtains" bit - that requires co-operation (utilisation) from "tenants"
Picking a species of tree that is dense, and tall enough (but not too tall), may be a thing to offer 99% blockout.
Agreed on both accounts Andy, the idea is to create a good wide "V" of blockout/shadow around the observatory, should any inside or outside lights get turned on/left on. The "tenants" will be well aware of the requirements of the neighbouring observatory when in use but anticipating times when closing curtains doesn't happen or is in fact impractical (eg. summer), other forms of mitigation will be needed. The good thing is, full understanding of my needs and a firm willingness to mitigate is at hand from the start
Quote:
Originally Posted by Wilso
You could also use contact film or paint the glass to stop the light rather than removing the windows.
Yes, something like this will also be done but as you say, takes time (years?) to be effective
Hi Mike
I have the answer. In Kmart you can buy small lights that take three AA batteries...very bright with new batteries..put them where you like..little magnet at the back...I have found after many years off grid portable lights are less bother.
I will try and post a photo as these are the best I have used...also a stack of garden lights outside so you can grab a couple and bring them in...I also had this approach when on the boat...
I have a few...some with run down batteries for dim light and others that you can read by.
Alex
The main thing I was keen to understand too was that while I recognise they can have a brightness issue, if LED's were considered, what type/specs/temperature etc are the most astro friendly?
I have a small cabin (currently somewhat dilapidated) very near my observatory that will soon be renovated and fitted out to be used for temporary and/or ongoing accommodation (not for me).
A number of light pollution mitigation solutions, like shielding, extended privacy screens and removing windows facing the observatory, as well as decent curtains on other windows, are all being planned in the design of the renovation and fit-out, to prevent/minimise detrimental effects on my observatory operations while the cabin is occupied at night.
Hi Mike,
Bugger all that.
Just get one of these war-surplus clocks left over from the London blitz
along with an Air Raid (ARP) Warden helmet and shout at visitors if you
see any stray light.
Just get one of these war-surplus clocks left over from the London blitz
along with an Air Raid (ARP) Warden helmet and shout at visitors if you
see any stray light.
That cracked me up. Great to have such a good laugh so early sets up the rest of the day.
And get a siren run it for five minutes before opening the dome.
Alex
Lamps are rated in degrees K with warm white being 3000K . I think you can get them down to 2500K without too much trouble or even variable. So if more red is better then you could try that. Also a dimmer circuit to reduce light power with programmable control based on time might work but you would have to ensure the lamps in the fittings are correctly rated for the dimming control and don’t buy cheap systems which may interact with other electronics.
Lamps are rated in degrees K with warm white being 3000K . I think you can get them down to 2500K without too much trouble or even variable. So if more red is better then you could try that. Also a dimmer circuit to reduce light power with programmable control based on time might work but you would have to ensure the lamps in the fittings are correctly rated for the dimming control and don’t buy cheap systems which may interact with other electronics.
Thanks Ray, all good to know
Quote:
Originally Posted by vlazg
Mike, i use these when i go camping, they can be either white or orange and are dimmable.
Thanks George, apart from being good for maintaining night vision, the less bugs under orange light makes good sense too and I think we will definitely go this way for any outside lighting
The colour rendering index CRI is what you look for in LED lamps
A CRI between 85 to 90 is technically equivalent to natural daylight in the light spectrum
Colour temperature in Kelvin K is what our eyes perceive to be a warmer colour ( red) or a cooler colour (blue )
Incandescent lamps were phased out by the Australian government a number of years ago , although you can still buy them at some retailer ??
The answer to your dilemma, turn off your lights and wear a red led head set with switch to operate everything