EDIT: despite the tendency for most folks to only look at the "pretty pictures" at the start of any thread, I've decided to "advertise" additional images I have or intend adding to the thread from this night (including maps) of very good seeing. (relatively-speaking!)
I'll start by inserting a larger scaled image of one of those below in Post #17 further down the page, & additional images further along as I process them: I'm not a fan of the plethora of over-blown images (imho) that populate the internet, but I think this one scrapes by as a balance of larger-scaling & still maintaining most of what I aspire to in detail, clarity & aesthetic refinement...& I'll also use it for a polar projection map basis later in the thread.
Hi all...well, the title of this thread says it all from me, the first really decent night's seeing for a long time notwithstanding anything we've captured in the interim.
We used the ASI462MC colour camera after we had the experience of clouds scuttling any imaging on the first night we were up there (Tuesday) - on that particular night the sky started out magnificently clear but by the time we were ready to capture the clouds were almost covering the complete sky - something we've experienced regularly this year unfortunately!
Through the thickening & thinning clouds we could see that the onscreen image was pretty nice - but to no avail as the clouds were too thick to attempt to image...only catching very fleeting glimpses of a really nice Jove in the manner I alluded to earlier today in Ray's thread...
With the prospect of the late appearance of the GRS (which has eluded us of late) & the GFS still suggesting that clouds & mist might encroach on the Yongala region we opted for safety-first & employed the colour camera again.
I really would have like to use the mono & if we had imaged the next night would surely have used it...as it was we had disassembled the scope & mount on Thursday morning intent on heading for the coast for some fishing r&r but after checking the weather forecast decided to head home Friday due to the gusty winds along the coast for the next few days - so no fishing!
Being at Yongala was great...no-one else around and just the faint light from a couple of house windows shaded through the trees from the nearby hamlet...& Wednesday night the clouds stayed away on the distant S-W horizon.
Here are 4 images from about 38 minutes prior to culmination through until 70 minutes after.....the seeing was somewhat variable but nothing really to complain about (Con! ) even if I am a perpetual "Oliver Twist."
But wait - later in the session Pattie thought it looked a bit strange onscreen when I shone the light onto the corrector plate for the constant de-fogging using the hair-dryer...I didn't get too worried as it didn't look too bad but in the morning I discovered that the primary was quite fogged: during the session we were using the hair-dryer after almost every capture & by the finish of the imaging session water was literally dripping off the scope everywhere!
I'll present these images in time order - very pleased to capture some extremely fine detail in the images as the GRS marches towards the CM - I've included a feed snippet from one of the captures (just randomly, probably not the best at all) & 3 small examples of the collimating procedure: de-focused star then moving closer to focus with a final feed very close to focus.
Observers will note that on first glance the star-feeds might look a bit shoddy but several factors need to be taken into account. (these were simply using the "L" filter (ir/uv cut) with the 462MC - I rarely bother with the red filter or ir610 filter with it btw)
With experience your eyes become adept at deducing what is actually happening with the Poisson Point & Diffraction Rings in these onscreen displays so although there appears to be a lot of distortion/aberration etc this does not represent poor collimation...as evidenced by the degree of resolution that the images reveal!
It should also have the consideration that the primary mirror is still "relaxing" at this stage after having the temperature of it dramatically reduced by the application of a 5kgm bag of heavily-salted ice applied to the C14's rear casing for about an hour before we start the scope up, find the planet & adjust the finder etc before targeting the collimating star...this to lower the scope's temperature to about 2°C below air ambient for the imaging start...which was about 6°C when we commenced imaging - ie, getting the primary down to about 3.5° to 4°C by then.
Edited by Kokatha man, 26 September 2021 - 02:52 AM.