fwm891

Why didn't you continue with the ball bearings and paint all but a small area facing the scope to avoid multiple reflections?

Superb little mount, very quiet and tracks/guides extremely well - shame if it goes but that's life I guess

The image below is one of a set taken last night. The early short exposure subs for framing didn't show the red patches. I'd left the camera running with an intervalometer recording 30 sec sub frames while I sorted out the OSC camera in the obs. Little horrified when I looked at the results. So I've been playing with the various switches on the lens and found that the patches only show when the 'VR' switch is active. To me that means that vNikon use a light source to dsetect the motion/vibration within the lens to activate the VR controls. Doesn't show at short exposures and certainly not seen under normal shooting conditions. So, switch off VR when using the lens for astro work with > 10 sec subs... Live and learn ⛈️ These comparison images have been heavily stretched. Upper No VR, lower with VR active.

Very nice set there Michael.

Once clouds dispersed I thought itr was going to be a great night.... I'd set up my Nikon with a 200mm lens to capture the wider spread of the tails and my cooled OSC camera on a telescope to look at the head and inner tail area. The Nikon and 200mm gave the framing I wanted but for some reason I've ended up with a red patch across the images (all frames) although not on the short set-up frames at the beginning? The OSC thankfully ran smoothly capturing 2 min guided subs. Below and two images one is a stack of 11 x 2 min subs the other is a single 2 min sub. I liked the colouration in the single sub but couldn't get the stack to match it. Try again...

Image edited

7x 120sec subs RASA 8 f2, IDAS NB-1 filter Guiding on comet head. Quick process in PI & PS