I do have a question pertaining to starlight focus and the best way to use live composite...but better to see the image and explanation first.

Ominous sky over south London.

We didn't get out hiking til mid-day on Saturday and it was super hazy and bright-basically nasty shooting conditions. The 70-300 macro capability is super dope though.

Again horribly hazy day and I restricted myself to isolation shots most of which were...quite frankly...trash.
[ATTACH alt="Ok so here is the image I wanted to discuss. See below. 24-70 S-Pro f2.8 at 3.5" via Live Composite "]3484071[/ATTACH]
Ok so here is the image I wanted to discuss. See below. 24-70 S-Pro f2.8 at 3.5" via Live Composite
For the sharp-eyed you will recognize the Chiltern area as the Ivanhoe Beacon. The night shot is from the south looking north towards the beacon trying to catch the Northern Lights-sadly non of that but I did indulge in my first attempt at light painting! Thanks Panasonic....now I have to go get a colored LED stick to further explore this :-D .
Anyway I was not prepared. I didn't have my tripod and had to improvise with a yoga mat and shoes to prop things up. I had an absolute devil of a time getting the stars in focus (pin pricks is what I was after). How can I best achieve focus in this use case?
Is it down to lack of tripod? Focus off the back panel was a nightmare with readers and I tried both auto (it locked once) and manual (saw blue on lights and things but was never sure. Lack of tripod had the camera grounded supported by aforementioned yoga mat).
I tried various shots from 1-3 minutes (ok earth moves bit of star smear expected?) and varied the ISO from 800-1600 and went from 3.5-5" seconds or thereabouts for each interval.
Also why is the light painting so sharp? And how do I completely blur myself out leaving just the light?
Finally I am a little annoyed to see that I picked up a couple of horrid dust balls that showed up in my blue sky quite badly requiring cloning out. I don't even change lenses in the field and looking back there were there from day 1. I may hit up warranty for a clean in this case as I am a little nervous hitting it with a rocket blower.
--
"Lead Me....Follow Me....Or Get The Hell Out Of My Way"
tedgphoto.com