Quote:
Originally Posted by John Hothersall
Seeing clearly not so good this time but best stretch of storm nicely on show. Your IR807nm is a real eyeopener, I got my first decent IR last night in a short run and I stacked almost all of them as they stayed in focus most of time. The IR shows a darker representation of the structure which is most interesting.
Just wondered Trevor what focal length would you push your system to on a 10/10 seeing night?
John.
|
Thanks John, yes the seeing was pretty ordinary mostly (about 5/10) with the occassional few seconds of steadiness which would have been up to about 7/10 but the former state persisted for the majority of the time. However, conditions like that are generally the bread and butter for my 807nm IR filter and considering the conditions, I am pretty pleased with how the IR came out. As you have noted, there really is some very interesting structure within the storm that comes up nicely in IR.
I have designed my new scope to get my imaging unit (Flea3+filterwheel+ 5x PM, which is one sealed assembly) to echieve focus as close to the wall of the scope as possible. This leaves me with a focal length of about 10 m. That is what I currently image at but if the seeing was very good I also have a 30mm adaptor that I turned up with my lathe that I could also use that would add another metre or so.
When Jupiter was at opposition the only way I could fit it on my 640x480 chip with the 5x PM was to unscrew the top section of the 5x PM and make my own very low profile adaptor to screw the optical section of the PM into and then screw the adaptor into the filter wheel making the whole thing a fixture, a sealed unit.
By the way, I have never seen 10/10 seeing, well not in Australia, on my trip to observe with the Keck's in Hawaii, one night on Keck I with Chuck Stiedel we had 1/3 of an arc sec seeing, reckon that would have been the best I have experienced.
