Just used up a week vacation I needed to burn up, stayed at home thinking I could have a few nights not worrying about having to wake up.
Well the clear sky took off a week also and sent the clouds in their place. Last night was the only clear night to go out.
It was pretty windy.? Weather reported 10mph, gusts to 21mph.? It felt like it.

For a reference, when do you notice wind affecting your G11?? I could not guide at all. Using a 115mm F7 with reducer and camera attached.
For me, out in an open field, 7mph is about max.

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There are a few options that may help in my (very novice) opinion.? Firstly, can you set up a windbreak?? I have a small section of mesh privacy screen that I put up on the prevailing wind side of my mount, and it really helps considerably.?? Another option is to bias the weight a little more than usual.? More eastward weight, and camera heavy.? This keeps the RA against the drive face of the worm, and also keeps the DEC against one side or the other, depending where youre pointing.? Some others use the weighted string trick.? Spring loaded worms can help reduce the need for biased balancing, but might not eliminate it all together.

Personally, with a big newt, Ill put the wind break up if its more than 8mph or so.? With a small refractor, I might be able to get away with 10 or 11 before I need the wind break.? With calm wind, I can usually guide in the .35 to .65 arc-sec RMS range, depending on where (and what) Im pointing.?? With 7-8 mph wind, that will bump up to .7 to .85 or so, with occasional spikes higher.? The wind break buys me a couple more MPH before the guide error is pushed higher.? Much more than that, and I really start to re-consider how much I really want/need that particular target.? If its going to be in view for a while, I might hold off for a better night.? If I dont have much time left, Ill push through, and just weed out the egged star photos.? I'll shoot shorter exposures in the hopes that fewer subs are ruined.? Perhaps someone else has a more elegant solution, hopefully something that can get rid of the clouds too.

Good luck,
-Tony

Also affecting guiding is where you are and local sky conditions. I live in Bortle 7 suburbia and my seeing is generally poor to begin with. 7 MPH is pushing it for me, even inside my roll off shed. Skyglow also effects guiding as there is not as much contrast between guide star and the background sky, and PHD2 (what I use) has a harder time seeing the star edges. But if transparency is above average I can usually tolerate a little more wind, though not always. Ground level windspeed can be low, while upper atmosphere layers can be moving around quite a bit causing the star image to oscillate.

But in general if I see 8-10 without gusts in the forecast, that's usually a session killer and I keep the roof closed. With gusting, there is also some concern of wind catching the rolled off roof where it's not as stable as when closed. Even if guiding under higher windspeed, your data won't be as good a quality, and fainter details in the target object can be convoluted. And probably longer focal lengths are more greatly affected, with 1500-2000mm or more being more sensitive than say 1000mm or less. Your 805?mm refractor may be more resilient than others with large Newtonians or SCTs, echoing Tony's statements.?

David,

I have a G11 and a C9.25" SCT. ?In western Oregon, I usually need a dew shield. ?This makes the scope a big sail, so imaging in wind over 5mph is a challenge at a long focal length. ?In the field, I use my truck as a wind screen. ?The G11 is certainly more wind tolerant than my Celestron CGEM II mount.

I am considering getting mesh and some PVC pipe to make a portable wind screen, but that means more stuff to carry and set up.

Mark