kirkster501

Yep, it's because clear skies are so few and far between that we have to desperately make the most of them when they do come along. In other countries with more clear skies it doesn't matter so much if you miss one, there'll be another tomorrow night probably. So yes, we are indeed knackered after a three night clear run, not that we get many of those. It takes a brave person to leave the rig going at night whilst in bed in this country. I never sleep easily when doing so.

My first light of my QHY268C as I discuss here: https://skastro.net/first-image-from-qhy268c-and-fsq85/ It took me seven imaging sessions on different nights to simply get 47 x 180 subs. I have done little else since due to the permacloud.

That would imply the same correlation across the world at new moon and that is manifestly not the case. It is the geographical location of North West Europe that is especially prone to cloudy skies. Also, even when at full moon, it is bright enough to burn through the high haze that would otherwise obscure all but the brightest of stars. That erroneously makes you think that it would otherwise be an ideal imaging night if that blasted moon wasn't there. But the Moon has nothing to do with it and it would be rubbish even if the moon wasn't there.

UK winters (and the UK in general) are notoriously cloudy and yet newcomers seem to have an emotional vision of them being crisp, freezing-cold with sparking stars in the sky with them being dressed in their cold gear and mittens with an hot chocolate looking at the stars. Sure, we get the odd night like that but they are very few and far between. They are nothing like that romantic vision; they are wet, grey and dreary affairs that sometimes go on for weeks on end. My longest such grey spell was the winter of 2012-2013 where it was clouded out for two solid months. Yes, imaging in the UK - and North West Europe - is exceptionally frustrating. There can be few places in the world more so. We live directly under the confluence of three major weather systems, a huge ocean directly to the West with the gulf stream directly overhead. In an average winter/early spring season over the last ten years, from empirical personal evidence, there were only two or three nights where I could leave my imaging rig running over night whilst tentatively going to bed. Even then I'd set my alarm for 02:00 and 04:00 to make sure there was no chance of rain incoming or a freak shower - always a possibility. Our friends blessed with better skies can collect more data in a week than I/we can in a year. That's why it is rare to see an APOD from these shores. For one it is difficult to build up the experience and secondly, the lack of clear opportunities to grab the required data. Such few opportunities mean that when one does pop up, it can often be spent sorting out gremlins and issues. I had that in the September night you mentioned where my mount would not track (PC issue it turned out). This is why it is so very important to use these less optimal nights to do dummy runs, even though you may not keep the subs. Without an observatory, it is difficult to motivate yourself to do that. Visual is, whilst still frustrating, very much easier. You can grab gaps in the clouds in skies where you could never image since the clouds would be over your target in ten minutes time..... I went to Lanzarote last December for a week and had a south facing balcony straight over the sea. Even in December, flips-flops and shorts and a hoody on (a brandy on the observing table of course ), I had seven straight nights outside on the balcony with my bins whilst my girlfriend and daughter were asleep, magnificent dark sky exploring South of the Orion area down to Canopus. Even there it can be cloudy but it was so nice to do this observing and it builds up your experience. I came home , hoping against hope to build up on this experience, and, lo and behold another month spell of cloud, cloud, cloud. Momentum lost. It is so incredibly frustrating. Despite that I love it and enjoy it hugely. I just wish so much that I could do this more often. Like we all do of course. But without moving to the Mediterranean/elsewhere, this will never happen The only alternatives are a remote rig in Spain/elsewhere as mentioned or to rent time on a remote telescope and, personally speaking, I could never accept a picture constructed from the latter option as "mine". Keep the faith and hang in there.

Some neighbours are really annoying. My next door neighbours' Leyandii have started to block my view to the East. It's the only place I have ever lived where I did not get on with a neighbour. He has ignored my civil and polite efforts to get him to trim them, probably because I had to involve environmental health ten years ago because of the three, ferocious barking Dobermans all night that he was forced to get rid of. TBH I will be leaving this house in a couple of years so will just live with it for now.

Thank you for your thoughts Alan. It is indeed a Lakeside focuser on my Takahashi FSQ85. The whole focus run in the focus plot above on the top post is 3705>4035 out of a total of 7300 complete range of the focuser. So I am only using a fraction of the focuser's potential stepping. Indeed, when I make the step size smaller, it'll be less than that even. I can't think there'd be so much of a delta difference in the "stiction" of the focuser in so small a total range of movement??? However, for sure, I will investigate this if dropping the step size does not address the problem. Your theory does hold water though..... I did indeed have to tighten this focuser a tad a couple of years ago (before I stared to use AF) because it slipped when pointing to the zenith even under a moderate imaging load. Hmm, (thought to myself) should I loosen it off a tad.....? I will try the smaller step size first and fiddle with the exposures a bit. Maybe even a slight lubrication of the focuser as well. It would be good if in SGP (or NiNA) you could adjust what you thought was an acceptable result in an AF run. I notice that anything below 90% causes a rerun. Would be good if that could be a configurable and tunable option for this sort of situation.

Cannot speak for ZWO but the LRGB CCD set from Baader is superb. They are 95% as good as the Astrodon ones at half the cost. I highly recommend them. https://www.firstlightoptics.com/rgb-filters-filter-sets/baader-lrgbc-ccd-filter-set.html The L filter has UV/IR cut and this is important when imaging with refractors to prevent star bloat. By way of contrast the Astrodon L filter is very permissive I feel, too much so.

As it happens, it is a ASI 120M mini guider that I am using here in the context of this thread, it that is what you mean.

All good tips guys, thanks. I've never had to do these adjustments before but, all the same, will give them a go.

Love my TEC140. Superb visual scope as well as AP.

Thanks guys will look into this further.

Thanks guys for your thoughts. The sky certainly seemed pretty good but I kept getting the warning chirps from PhD with even the tiniest whisp of passing high level mist for a few seconds, the stars were still perfectly visible through it. Cannot wait for crystal clear skies in the UK or we'd never get anything done.

I have seen this issue before too. Did you calibrate PHD properly? Has it remembered the calibration from another scope setup and is using that instead of the current one? With my mobile rig it needs to be calibrated every time I set up or else I get issues like this. Did you calibrate near the Celestial equator which is the best way to do it?

So you feel I am wandering too far from focus when the focus routine starts? Ok guys thanks, I will try much a smaller step size next time out. I have indeed always used nine steps, 2x2 binning and about 4s exposures and changed it to seven steps only that night to experiment. I often get a "focus failed, assuming focus is outwards" (or words to that effect) when it runs the second (and third) times. It is intermittent, flip a coin if it works or not. When it does work I can get a perfect "V" but when it fails the left hand sample (occasionally but less so the right hand sample) - like downturned wings. I just never feel I can leave the rig to do its thing and every autofocus needs to be supervised, as things stand currently.

I am putting it on the Redcat the next clear night. I believe this camera and that scope is a winning combination.