Thanks Guys.
I don't think it was a capture problem. I think something funny happened when I was processing in registax... it happened on a couple of other avis as well.
Yes you are right Mike! It would look a lot better with a black background. I just slapped it together really!

I will have another go at this one, both in autostitch (I think I have it on the lappy) and by reprocessing the offending avi... and I'll rotate it to make it a panorama type layout with black background when I'm happy with it.
...but it won't be tonight!

Clear skies, and a newly arrived 2.5x Powermate and 13mm Nagler are suggesting to me the serious need to get out in the field and observe!

They put up such a strong argument... it's hard to object...
Al.