DSC 31 July - 3rd August - Report Including kit disasters

[Carole]

I went on Wednesday as the forecast looked good for that evening.  I was joined on Thursday by Dave from Swanley one of our regular non members and Noel came for the first time.

As a social event it was great, lots of interested public around, some VERY interested. 
Noel now has a list of things he must remember to bring next time - Ha ha!

The skies on Wednesday night were pretty clear except for about 1 1/2 hours around 1 - 2am.
Thursday was cloudy so Noel and i watched a video and drank wine.
Friday was the best of the lot.  It was forecast to be clear until 1am but in the event it was clear all night.

From a personal perspective I had a most disastrous time with kit not working right and wasted most of the clear skies battling with problems.

Problem1: I mounted my usual dual rig but with the cameras reversed as I planned some large and some small targets, so the smallest camera went in the smallest FOV and my larger camera going in the WOZS71.  I had a very interested camper looking over the top of my camping obsy watching me polar align which went well.  He also was keen enough to help identify my target when I thought I hadn't actually found it.  I then remembered I hadn't focussed, so synced on my target so I could come back to it and slew to Vega to focus at which point we heard a "clunk".  Looking with the torch I could see the focusser of the ED80 had slipped right down to the end with the camera and Electronic filterwheel attached.  Now I know I had locked both focussers as I had been telling my observer what I was doing as I went along.

GOOD BIT OF OUTREACH HERE HUGH!!

I had previously had a similar problem a few months ago with the same scope and had put it down to me not tightening the locking nut, but I knew this time I had definitely done so.

So decided not to use the ED80/Atik428/EFW and just focussed the WO/Atik460EX as I was doing a large object anyway.

Problem number 2:

Focused and slewed back to the Shark Nebula and started up the guiding (still being watched).
Finally started to image, but all my subs except very short ones were coming out with trailed stars.  Guiding was perfectly fine getting RMS 0.05 at one point and the graph was good.  Could not fathom it out.  By the time I had messed around trying to work out what was going on it clouded over and I decided to call it a night.

Thursday I decided to remove the camera and EFW from the ED80 and re-balance the rig as maybe the elongated focuser was causing an imbalance?????????????

Friday.  got up and running quickly, re-found the Shark Nebula and started trying to image again.  Once more I was getting trailed stars with good guiding.  By 2am I had still not fathomed out what was going on, cables had been checked, nothing was loose.  I had by this time started ( in desperation) gathering Luminance binned x 2 to try to get the same amount of data but with shorter subs, but as time went on the trailing was happening in shorter and shorter subs.

Dave and Noel had tried to offer advice, and having gone back to park several times, changed the guide cable, tried a different guide programme and re-checked the balance, checked everything was tight and no snagging cables I was just about pulling my hair out.  We tried to work out what was going on and Dave suggested it was bad PA but I knew I had done it OK with Polemaster two days earlier.  However I noticed every time a new sub landed on the software screen it was slightly shifted from the previous one (but with guiding???)  But having run out of ideas, I stopped once more and re-checked the PA, which WAS OUT!!!  But why???

RE-polar-aligned and finally I was able to get subs without trailing.  thinking back on it, there was one thing that I had to tighten and that was the screw underneath the spreader and I am now thinking that maybe I hadn't spread the tripod legs 100% and the legs perhaps had slipped to fully open at some point and this had put the PA out.  I have never encountered such issues after almost 9 years now of DS imaging. 

Problem number 3.
Having gathered a fair bit of RGB binned I decided to use the remainder of what was left of the night doing 600sec luminance.  This has come out OK but all the binned data I took of RGB and the binned data I took of Luminance in desperation  has yielded nothing that could be processed,  there is no histogram at all even though there are stars. 

Edit on Sunday 4-8-19:  Tried re-stacking the subs again today but just using Flats for calibration, and I have rescued the RGB.
No idea what happened to the data last time.

So all I have ended up with is 1 hour 10 minutes of luminance.  So this is definitely a work in progress.

Noel has kindly taken my ED80 Crayford focusser home and taken a look at it, hopes he has fixed it.

Phew!!

What a waste of good skies.

Gonna have to check the mount and ED80 out before I go to Kelling in September.

I am sure Noel has some disasters he can add to this, I know his battery ran out.   

Carole

[Carole]

So this is all I got after 2 evenings imaging - very much a WIP.

Lum 600secs x 7 Atik460EX and WOZS71 HEQ5

[ApophisAstros]

Sorry  you had problems . carole.
I suppose if this could happen to you i should prepare myself for such trifles in the future as i add to my kit, moral of the story the more you have the more to set up take down and go wrong.
Roger

[Carole]

I still don't understand why the RGB data I took binned which I have done loads of times previously did not yield any data that was processable. 

the more you have the more to set up take down and go wrong

That's basically why I prefer not to add to my system with things I can do without, such as EQMod, Plate Solving, Hubs etc etc. 

Carole

[NoelC]

Thanks very much for Organizing this Carole. 
Really nice weather too.  I can recommend the Rose and Crown in Burwash for food.

Things I forgot:
Dew heater (actually took it, but couldn't find it)
Decent power cable (the one I had dropped a volt over it's length)
Memory Sticks
Decent power supply (the one I took was nowhere near powerful enough and the battery backup lasted an hour before starting to fade).
Apart from that everything went smoothly.

[Carole]

You should use the hook up Noel, saves having to worry about batteries going flat.

Lovely to see you there though and pleased you are planning to come again.

Carole

[ApophisAstros]

Thanks very much for Organizing this Carole. 
Really nice weather too.  I can recommend the Rose and Crown in Burwash for food.

Things I forgot:
Dew heater (actually took it, but couldn't find it)
Decent power cable (the one I had dropped a volt over it's length)
Memory Sticks
Decent power supply (the one I took was nowhere near powerful enough and the battery backup lasted an hour before starting to fade).
Apart from that everything went smoothly.

yes i have eaten there Noel,agree really nice,
Roger