Thanks Bent and Akira. The last image is also my favorite among them. This has been my first opportunity here too - it is not that often that it is clear sky over the Alaska Range.
It was a useful exercise as I also got a better idea about exposure. I was a bit surprised how much dimmer Jupiter and Saturn was compared to Mars. Part of that is all the atmosphere at this low angle. It looked like 300mm at f/4.5, 1/20sec at ISO100 would give an exposure of Jupiter that was a little more than 1 stop away from being saturated in the red channel (perhaps with a little more margin in the raw data), so if I were to use stacked converters that takes 3 stops at ISO 160 with my AW1, I should not expose shorter than about 1/2.5 sec for optimal exposure of Saturn without blowing out Jupiter. Perhaps go up to ISO 400 to be able to expose at 1/5 second. The first exposure above intended to blow out Jupiter to clearly show Saturn was already at 1/2 second at f/4.5 and ISO 100, and histogram on Saturn approximately butting at the right edge.
At the conjunction the distance between the planets will be only about 1/10 of what it was now. Even a few days within December 21 on either side should be pretty spectacular, so do not give up and make sure to use an early or late opportunity. Planets sure move slowly relative to each other when seen from earth. (Conjunction between our moon and the planets is an entirely different matter.)
The shrinking MarsTo illustrate this point, below is a summary showing change in apparent size of Mars since shortly before its closest approach October 5, and opposition October 13 (slightly further away) to December 11. Remember how popular media was talking about Mars becoming
so much bigger the last week before closest approach? The change does not appear to be linear - not much change around that time but it is shrinking pretty fast week by week now. I am not sure if I will continue this
Size of Mars imaging project with literally smaller returns now, so the results are presented here.
(First image Sept 29 with AF 300mm f/4 and TC-301 only, the next TC-14E + TC-301 stacked, thereafter 300PF with TC14E + TC20EIII stacked. Image scale compensated for 2% difference in effective focal length between AF300 and 300PF, and for lack of the 1.4x converter in the first one. All images captured with AW1 at ISO 160 in burst of 15 frames per second. Irregular interval between imaging mostly caused by suitability of imaging conditions.)
A little side note here is that at the Cloudy Nights (CN) forum there have been a number of posts lately showing images with signs of dust storms embracing large parts of the southern hemisphere of Mars. If one looks
very closely at my November 17 and December 04 captures near the southwestern edge (and perhaps on the south-eastern edge too in the first of the two) there is a blueish-grayish area not present in the earlier captures (not talking about the south pole). I could to some degree correlate them with captures on the CN forum and Mars maps. This might well be those dust clouds. I never dreamt that I could record weather on Mars with a regular 300mm lens and some stacked converters.
