How to Cope with Wind when Stargazing?

[scarp15]

Sandbag, that was my thought as I was driving home tonight from an attempt to make something of a clear sky forecast. Arriving at what I hoped would be a reasonably sheltered site from strong gusty winds that are currently sweeping across from the west, it was  in fact very gusty and so not as sheltered as I had hoped. The sky was clear, quite seductive so I determined to set up the scope anyhow, my 8" OOUK dob. Angling the dob horizontal, hastily turning to go back to the car, the crashing sound was quite instant as a strong gust flipped the scope onto its side. Mercifully the mirrors seemed to look OK on a rough inspection, the finder scope shoe had become loose and the focuser adapter cap was temporarily missing, thank goodness it had not been my 14" dob.  After this I clung on and attempted to observe M42 and sweep through some of the clusters near Monoceros but the wind was not relenting and carefully dragging things back into the car soon became necessary. I regretted not having my binoculars because they would have been more suited to the conditions, which registered an ave SQM-L 21.19, quite good for this particular location and benefitting following a few hours of light rain. 

So a sandbag on the dobsonian base would have assisted but lesson learnt, not to be repeated, next time take binoculars or stay indoors - the scarcity of good clear skies falling on a new moon phase at a weekend do sometimes lead to not the best of decisions. How do you cope with windy nights when its clear, sandbag et all?   

[Geoff Barnes]

It's going to be really hard to avoid any gaseous jokes in this topic! ?

I must admit my 12 inch Dob is a bit of a wind catcher, wobbles terribly.

[John]

If it's gusty out, I tend to use a refractor. Less tube diameter to catch the breeze.

 

[Geoff Barnes]

As John says, a small refractor is going to catch the wind less than something like a big reflector.

However, I suppose the only real solution is to have the scope in an observatory of some sort to keep it protected from the wind.

Cost and practicalities obviously preclude many from such luxuries, even a fence or a wall to shield yourself may have a limited beneficial affect, though not ideal.

I think very windy nights probably need to be treated the same as overcast ones, no good for astronomy. ☹️

[clarkpm4242]

Forestry Commission fire roads orthogonal to the wind direction.  Limits the horizon though.

Also, sounds quite freaky on your own...

...cheers

Paul

[Guest]

20 minutes ago, clarkpm4242 said:

orthogonal

Googled it and still none the wiser

 

[clarkpm4242]

19 minutes ago, AstroCiaran123 said:

none the wiser

Examples:

Wind blowing from west, fire road running north to south.

or

wInd blowing from north west, fire road running south-west to north-east.

[Froeng]

58 minutes ago, AstroCiaran123 said:

Googled it and still none the wiser

 

Orthogonal = rectangular / at a right angle or 90 degrees.

Also think about orthoscopic eyepieces, they are supposed to show a rectangular grid pattern without distorsion, ie “ortho”Scopic.

hope this clarifies

Best Regards

Frank

[chiltonstar]

I have an old beach windbreak (two poles and canvas) that I use sometimes - acts as an LP screen as well. I also use a small frac set on a tripod at the lowest height setting when it's really windy as it is less affected.

Chris

[David Levi]

I don't have a solution to the problem but I just wanted to say that it was a good effort to try and get out and observe. I was being buffeted by the wind with my 8" reflector on Tuesday night. Luckily the wind died down after an hour and the session was a good one. But there's nothing more frustrating than looking through an eyepiece at stars jiggling about, especially when the atmosphere is really clear.

[mikeDnight]

Build a run off roof observatory! Even from town, having the walls as a wind break and light shield, pays dividends. Comfort is as important as a good scope, good eyepieces etc, as without it you'll be distracted.

[RobertI]

Sorry to hear about the accident hope the dob is ok. If it’s windy and there’s a sky not to be missed, I put my shortest scope on my heaviest mount. The extreme example is the 72mm frac on the Skytee and 2” tripod, pretty immune to windy conditions. The C8, being short, can also cope with light winds when on the Skytee. Unfortunately the wind seems to swirl round my garden so there is no sheltered spot. ?

[scarp15]

Quote

Its going to be really hard to avoid any gaseous jokes in this topic!?

Yes I thought that after I'd posted.

 

12 hours ago, John said:

If it's gusty out, I tend to use a refractor. Less tube diameter to catch the breeze.

 

Yep I did think about this to John and as others have also suggested, with tripod at lowest setting etc. Somehow I felt that if something was to go wrong, illogically perhaps, I'd rather it happened to the dob and not the frac, as though in comparative terms, its a tough old mountain bike and not a slick fast yet flimsy roadster. However the TV 85 could be considered a tough old refractor to. The OOUK 8" dob base is quite tall and narrow so perhaps probably asking for trouble. 

 

6 hours ago, clarkpm4242 said:

Forestry Commission fire roads orthogonal to the wind direction.  Limits the horizon though.

Also, sounds quite freaky on your own...

...cheers

Paul

I know, forestry plantations can creak and groan quite a bit in the wind. There is an enclosed car park near to another location I venture to that might be worth considering if this situation was ever to be repeated.

 

3 hours ago, David Levi said:

I don't have a solution to the problem but I just wanted to say that it was a good effort to try and get out and observe. I was being buffeted by the wind with my 8" reflector on Tuesday night. Luckily the wind died down after an hour and the session was a good one. But there's nothing more frustrating than looking through an eyepiece at stars jiggling about, especially when the atmosphere is really clear.

Cheers David, like you I have been buffeted by wind before, gaining an ideal circumstance is not easy and some windy conditions are often a compromise. It is frustrating though trying to gain a steady enough view and there are places I will avoid when windy, not sure there is an exact technique just hang on by your finger tips I suppose.

 

3 hours ago, mikeDnight said:

Build a run off roof observatory! Even from town, having the walls as a wind break and light shield, pays dividends. Comfort is as important as a good scope, good eyepieces etc, as without it you'll be distracted.

That could be a good plan Mike, currently our yard and what had at one time been my best vantage point, is presently occupied by the rabbits rather elaborate den.

 

Thanks for all the suggestions, the beach wind break, using a heavy mount, perhaps weighing down the mount, potential solutions in the right circumstance. Often if there is a good forecast and with time to make something of this, certain risks or decisions need to be taken. The previous time I was out, it was the condition of the backroads that was of concern, following snow and ice and an air temperature of almost -10c, preparation and care required a bit more extra thought and effort. Each of these times though are part of the whole eventful stargazing experience.    

[mikeDnight]

I'm pretty certain the rabbits won't object if you were to upgrade their hutch for an observatory. Just don't step on them! 

 

[paulastro]

I'd recommend not eating baked beans or curry before an observing session ?

[Guest]

Been there...

[Paz]

I avoid very windy conditions partly because of the vibes but mostly from worrying about the wind blowing bad things onto the scope lens or mirrors.

[scarp15]

Definitely not good when pollen is circulating and obviously if located near to a coastal stretch, wiping up sand or grit. Mostly I go to places that are grassy and with some light gravely surface. Often some gusty wind / breezy condition (non scope toppling conditions!) just seems to almost always be unavoidable, at least where I go, but this will though keep moisture out of the air. I had always taken along and would begin observing with binoculars, I need to get back into that habit.

 

[SIDO]

I have done this a few times back when I lived in the big city, wind did not seem bad so I embarked to my dark site only to find it unbearable out in the boonies. Surprising how much of a windbreak civilization can be...

I did that a few times like I said then started to catch on and adjust, the van is a better wind block than the car, a tarp and some rope can save it if there are things to tie to, like John stated a smaller profile instrument could be substituted if one always has it handy but becouse its small and you should have taken it and did not the self kicking will have you soon catching on just as I.

Always good to have a few dark sites in your porfolio too as some may have better wind block advantages for various different directions and intensities.

          Best of Luck Everyone ?

                          Freddie...

[Phil Fargaze]

If I find myself at a windy star party (and I don`t mean the baked beans!) I take a couple of wooden pole and nylon windbreaks and surround the dob.  Plus there is the car to use as a shield as well. The windbreaks have four poles each so they are a decent length. I try not to forget the mallet, otherwise I end up searching the undergrowth for large rocks. All part of the fun I suppose.

[NGC 1502]

 

As mentioned the OO UK Dobsonian base can be too narrow, depending on which model, and more especially the 150 & 200 mm, and prone to being blown over in windy conditions. Not knocking OO, but the otherwise excellent Dob base can be made more stable by extending the three ground plate arms.  Use at least 30mm x 18mm aluminium solid bar bolted to the three arms of the ground plate. The 3 original feet can be bolted to the end of the new extensions.

The ultimate in tall and skinny was the out of production OO 150mm F11,  great apo like views, but just waiting to be blown over. I recal seeing one modded with heavy weights attached to the base to help stability.

The 10” and larger are better in terms of stability, more weight helps.

Ed.

[scarp15]

On ‎05‎/‎03‎/‎2019 at 07:50, SIDO said:

Always good to have a few dark sites in your porfolio too as some may have better wind block advantages for various different directions and intensities.

          

Different sites in your 'portfolio' can provide options dependent for conditions. I prefer open locations that attract night breezes, the site used on that windy night provides a bit more shelter, but is still relatively exposed. Gaining a selection of places to go that are reasonable for a same night return home bound journey, dark enough to be worth while, discrete with little chance of encountering anyone, good vantage for lower level observing, geographically widely located to take account to favour varied localised weather patterns, can be quite an achievement in itself.  

[Beulah]

On 03/03/2019 at 06:55, clarkpm4242 said:

Forestry Commission fire roads orthogonal to the wind direction.  Limits the horizon though.

 

...cheers

Paul

But great at improving sky contrast and limiting light pollution...