Under starters orders

We live in a 'Dark Skies' area here in Central Brittany, there are a few street lamps in our nearest village, well when they can be bothered to switch them on, so when the sky is clear you get to see  a rather spectacular starscape. Now as I have set myself the challenge of mastering light painting with both torchlight and flash/strobes., this week it will be torch power.
​ Now as it's a learning process for me I might as well pass on some basic settings to you.  Camera is set up as follows.. Nikon D750 (including it's brand spanking new shutter), the highest quality RAW file, Nikon 20mm f2.8 set at F4.5, iso 200 and with a 30 second exposure time, noise reduction applied in camera which will delay the image appearing on the camera screen by about 30 seconds.  This is 3 exposures, one for the ambient, one for the main building (ma maison) and one to twiddle in the bits missed, all loaded into Lightroom for some lens correction and then opened as a layer stack in Photoshop, masked faffed and saved back into Lightroom for some perspective control and some clarity painted into the sky to 'pop' the stars. 
So I used no colour gels on the torch but I'm just getting used to a standardised group of settings before the real creative stuff can bob to the front of the queue. Going to switch off the in camera noise reduction and use my Yongnuo strobe trigger on camera as it has an auto focus grid pattern that it throws out to assist the autofocus in the pitch black, which should be better than me , torch in one hand trying to fathom out what is in or out...
Now 30 seconds shows up a small amount of movement in the stars and if you google astro photography there are plenty of formulae out there to work out your max exposure time /focal length combination to freeze star movement. Now then I'm already looking at very high flash sync to kill ambient light in daylight conditions...but I'll get these techniques nailed first..