Jump to content

Banner.jpg.b89429c566825f6ab32bcafbada449c9.jpg

Sky Quality Meter


scarp15

Recommended Posts

33 minutes ago, estwing said:

Mob are in Skye in October....I might get a meter for it

I would if I were you, collect numbers to help people work out the best places.

 

PEterW

Link to comment
Share on other sites

39 minutes ago, PeterW said:

I would if I were you, collect numbers to help people work out the best places.

 

PEterW

TBH Peter you really don't need a meter reading to tell you that the isle of Skye is dark..............very dark :evil62:

  • Like 2
  • Haha 2
Link to comment
Share on other sites

3 hours ago, swamp thing said:
3 hours ago, PeterW said:

 

TBH Peter you really don't need a meter reading to tell you that the isle of Skye is dark..............very dark :evil62:

unless that pesky Aurora is about again...?....:hiding:

  • Haha 2
Link to comment
Share on other sites

What is apparent and others who venture to find a darker sky than home, will understand, is the extent you may have to go to erase any trace of light dome. At home, sky glow is familiar and it is easy to become complacent. I still find it quite shocking that an hours distance or more  from the city and to arrive at a purported dark venue, is still infected to a greater or lesser extent by a light dome in one direction. What I have equally become aware of though is how dark the other (usually north) direction can be. A SQM is an asset to be able to monitor each time you visit a place and perhaps evaluate if there could be somewhere else near by to explore as a potentially darker zone. Also if on the Isle of Skye and you happen to encounter great dark sky conditions (Aurora aside of course), I personally would be eagerly wiping out the meter to take those readings.   

Link to comment
Share on other sites

gonna be harsh here but pls don't think its aimed at anyone just MHO, I don't need a meter to tell me how dark it is, I ONLY observe on a new moon in Dark sky areas..if its 21.6 where we are I'm unlikely to move or try somewhere else for a reading of 21.8. I drive to a couple of very secuded spots with good mates.

If I take a reading that's fantastic and tell you where they are, chance is they wouldn't be secluded for long!...sorry but I've done the leg work...you do yours.

like I say this is not a dig at anyone just my 2p...

  • Like 2
Link to comment
Share on other sites

Readings are valid as a personal reference and for informing others, monitoring sites for club meets, as has been mentioned. They could historically be helpful to monitor if an area has deteriorated over time, or by dark sky protective awareness measures, even improved. If there is to be an inappropriate development proposal, meter readings could assist a pressure group, not least where natural habitat is threatened by excessive light distortion. Quite understand that if you have a secluded place and if conditions are good potentially 21.6 mag sky, you will wish to just enjoy those periods of clear sky. However the relevance is not between chasing assumed 21.6 to become 21.8, more so based upon a location that could achieve mag 21.1 - 21.2, compared to exploring somewhere another twenty minutes journey away and gain readings of 21.5, this then becomes significant for observations.  

  • Like 3
Link to comment
Share on other sites

1 hour ago, estwing said:

 

If I take a reading that's fantastic and tell you where they are, chance is they wouldn't be secluded for long!...sorry but I've done the leg work...you do yours.

Agreed on all counts!

  • Like 1
Link to comment
Share on other sites

3 minutes ago, Beulah said:

Yep, tell me about it.

TBH tho...if I posted a reading that blows most locations away you STILL wouldn't motivate some people into making the effort...sad, but true.

  • Like 2
Link to comment
Share on other sites

I was given one by a very kind guest and use it regularly. It's useful for an imager because we are constantly losing our adaptation thanks to our computer screens, so it is very hard to make a meaningful check on the sky visually.

Since my home is also my dark site I can comment on the variations seen in the SQM. On what we call 'clear nights' our readings vary considerably, between 21.4 and 22. Below 21.4 you generally think it looks a bit hazy. To distinguish between 21.5 and 22 I think you'd need to have some reference test stars since a casual upward gaze doesn't tell you much. This suggests that you need to make a number of readings at the same site in order to build up a real picture of its quality.

Sometimes I have the feeling that the transparency is mediocre when I step outside and am pleasantly surprised when the SQM says it's actually good. This impression never works the other way round. I never think it's good when it isn't.

I used to have a collection of remembered test stars for estimating the transparency but my sight has degenerated so much that I can't see half of the blessèd things on a perfect night these days. Such is life! 

Olly

  • Like 5
Link to comment
Share on other sites

With so many factors to consider, it would be nice to perhaps learn of, if from a reliable reading, someone actually did register above 21.6 within the British Isles, based upon a successful dark sky trip.  

Link to comment
Share on other sites

26 minutes ago, estwing said:

TBH tho...if I posted a reading that blows most locations away you STILL wouldn't motivate some people into making the effort...sad, but true.

I think though Calvin that there is the what if, that many will reckon with. When the forecast emerges as anything but the promise of clear sky, if with a group, sure you might drift off to a pub or whatever, or accept defeat and head home if on your own, questioning your sanity and motivation as you do. Then, soon after, only becoming yet more determined to go back for more - as next time it will  be clear and great (of course it will). This is what marks it differently to anything else, you require that extra drive and stubborn determination that just might become rewarding and memorable, not the same if your out for the day mountain biking for example, don't matter if turns out wet and muddy.

  • Like 4
Link to comment
Share on other sites

1 hour ago, scarp15 said:

This is what marks it differently to anything else, you require that extra drive and stubborn determination that just might become rewarding and memorable,

Yes! It’s that constant returning to that target you just can’t see for that one time that everything comes together and it’s visible. Some of my very best times in this hobby have come from the elation of finding something rather than simply being blown away by what I was seeing. First time seeing the Veil and finding the Intergalactic Wanderer after an hour of searching spring to mind. You need the determination to solve the challenge and succeed! It’s the challenge that I love! Slightly off topic but that comment really struck a chord with me!

  • Like 1
Link to comment
Share on other sites

8 hours ago, scarp15 said:

With so many factors to consider, it would be nice to perhaps learn of, if from a reliable reading, someone actually did register above 21.6 within the British Isles, based upon a successful dark sky trip.  

If anyone is going to find those 21.6+ mag skies it will be you Iain, IMHO. You are very close already...

  • Like 1
Link to comment
Share on other sites

9 hours ago, estwing said:

TBH tho...if I posted a reading that blows most locations away you STILL wouldn't motivate some people into making the effort...sad, but true.

You want to know what's really sad ... there are occasions (I'm not going to say how many, but just think of a number and increase it) when it's a clear sky and I can't even make the effort to set up at home. Must be getting old!

  • Like 2
Link to comment
Share on other sites

1 hour ago, estwing said:

I don't observe from home anymore...pointless for what I look for really 

Given that the SQM scale is logarithmic Calvin I would have though mag 21.8 was well worth seeking out for your type of observing.

  • Like 1
Link to comment
Share on other sites

45 minutes ago, Stu said:

Given that the SQM scale is logarithmic Calvin I would have though mag 21.8 was well worth seeking out for your type of observing.

This has to be true. However, the faintest objects are most susceptible, I think, to their location in the sky. The zenith is the place to be - if the object is obliging enough to pass through it.

Olly

  • Like 2
Link to comment
Share on other sites

14 hours ago, estwing said:

If I take a reading that's fantastic and tell you where they are, chance is they wouldn't be secluded for long!...sorry but I've done the leg work...you do yours.

I have changed my thoughts on observing over the last few years with regards to revealing to others where I go.

Not to go off topic but it's not only about the sky quality. I like the peace and quiet visual observing brings, either being out on my own or with like minded others. You can concentrate more and pull out more detail whilst verifying what you have seen.

As Calvin says I/we travel miles and do a lot of research into spots to observe from. I have thought about a SQM but would only state a general area nowadays if I was to post the readings. 

Apologies to those that are serious about the hobby but good secluded sites are hard to find and not easy to share after all the effort hunting them out. 

 

  • Like 3
Link to comment
Share on other sites

2 hours ago, Stu said:

Given that the SQM scale is logarithmic Calvin I would have though mag 21.8 was well worth seeking out for your type of observing.

And that's why I go to the Isle of Skye....£80 for a week in a bungalow in some of the darkest skies...

  • Like 3
Link to comment
Share on other sites

1 hour ago, mapstar said:

I have changed my thoughts on observing over the last few years with regards to revealing to others where I go.

Not to go off topic but it's not only about the sky quality. I like the peace and quiet visual observing brings, either being out on my own or with like minded others. You can concentrate more and pull out more detail whilst verifying what you have seen.

As Calvin says I/we travel miles and do a lot of research into spots to observe from. I have thought about a SQM but would only state a general area nowadays if I was to post the readings. 

Apologies to those that are serious about the hobby but good secluded sites are hard to find and not easy to share after all the effort hunting them out. 

 

I get that completely Damian, concentration is a core reason for observing, whether solo or with like minded people. I think that for presenting reports on here, it really would be good to see a reliable reference to SQM readings, without being too specific in terms of where your location actually is. I also have two minds regarding how much location information to make transparent on the forum. Some time ago I was traveling to reach a dark sky location that I have used many times, on the backroad approach and pulled in pretty much just by a farmers gate, I was very surprised, nay startled to see a white skywatcher dobsonion stand out in the car head lights, the occupant probably in their car. At that time I felt that I should have pulled over and invite the person to put the dob in the car and follow me to a much better site. However I had my own agenda and did not, probably would have frightened the life out of him / her anyway just by pulling up in what is a remote place.  

I am not completely sure that disclosing a little too much detail would suddenly unleash a wave of interest and enthusiasm by members on here to invade a special place. If you up-load on YouTube or Twitter maybe, I understand though that it is best to be cautious. The locations I use are also based on research, although at least the approximate vicinity is publicised within Northumberland dark sky park data and at some places I have occasionally seen night scape photographers. My plans to go wild camping though will rouse little attention other than perhaps a curious passing sheep. This debate for monitoring sky brightness I intend to widen, to include folk who go backpacking / wild camping in particular, as many of these people are primarily located to include as part of their wild camping experience, appreciation of a dark sky and therefore could extend this to be monitoring the Bortle Scale for their remote night sky.  

  • Like 3
Link to comment
Share on other sites

I agree totally what has been said about giving out information on a precise location. I suppose we need to remember that this is a totally open forum and the discussion can be seen by anyone member or not. Its regrettable that someone, not interested in astronomy, will think 'expensive equipment' I will seek that location out.

My Astro Society does advertise its observing dates and location but about 12 members turn up on average so its safe from that point of view.

So stating Elan Valley or Isle of Skye gives members a general opinion on the dark site which I think is good enough.

  • Like 2
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.