here’s another lunar image from April 23rd: Pitatus – one out of the ‘problematic’ footage. After fiddling with AS and Registax without much success I finally placed a number of alignment points in Registax5.1 manually, processed the AVI twice with different alignment regions and combined the best areas of both runs in PS. This footage seems to fool the automatic AP evaluation in AS and Registax.

Click image for full version with details

The results is not too shabby, resolution is on par with my Pitatus captured 2008 with the C9.

Pitatus is a fascinating crater with it’s lava flooded floor featuring many rills, cracks and craterlets that are a good indicator for the resolution achieved. At least as fascinating is Hesiodus A, the CC (concentric crater) at the bottom left of the image. The reason for the concentric ring formation of CCs is unknown today, it’s safe to assume they are not formed by any kind of double impact.

Cheers, Oliver

after my lunar imaging session on April 23rd I almost called it a day (night?) since the seeing worsened substantially at lady lunar. I was about to break down the equipment but decided to take a final look at Satun. To my surprise the view was quite stable and well defined in the eyepiece although Saturn was located above my roof top and less than 40 degrees afar from the moon. Sometimes I really don’t get the mysteries of seeing
I fired up the already stowed away camera again and shot 4 AVIs: RGBR. Transparency was really bad that night so that I could only use 1/19s integration time for R and G and 1/11s for B. Capturing ~4000 frames at 7.5fps for the blue channel took forever.
The AVIs have been processed in AutoStakkert and sharpened in Fitswork with the iterative Gauss sharpening. This gives the best results for my Saturn captures and enhances noise virtually not at all. Wavelets produce a lot of noise used on my Saturn captures and enhance cloud banding much less – quite in contrast to my lunar captures where wavelets work best by far.
The RGB image is the result of the G,B,R imaging sequence. The result shows the Rhea-transit shadow and Titan. I aligned Titan on the R and B channel to it’s position in G and enhanced brightness/contrast partially. The cloud bands show some small details, most prominently above/below the rings and I’m not 100% confident these are real features. I created an contrast enhanced animation of both red captures but two frames aren’t enough to really tell all the features are real.
After the last R capture seeing also diminished at Saturn, time to end the session…

Click image for full version with details

Cheers, Oliver

reasonable results of my Plato and Pitatus captures from April 23rd are still pending. I tried Registax 5.1 with the Plato AVI yesterday without success. A first run with a single alignment point to check out the AVI’s potential lead to a good but not spectacular result near the alignment point, a sharp crater rim and craterlets close to the AP well defined. Multipoint processing was not that good. The automatic MAP selection resulted in a horrible image with alignment areas washed out and harsh seams between the areas, carefully choosing 12 points manually wasn’t much better
Ok, I switched back to AVIStack. The first AS processing I tried was fine outside the crater where the harsh terrain has good contrast for the AP tracking. Only the crater floor was completely washed out. I parametrized AS as suggested by Michael Theusner himself and others with increased correlation area radius and higher smoothing factor settings. The estimated  processing time of 8 hours compared to a fraction of that before required running the job overnight. Unfortunately Windows 7 decided to reboot after updates during the night although it shouldn’t, needless to say all processings are lost Jeez, who’s programming this stuff…
I’ll retry today, if AS still has issues on the contrastless crater floor I might switch back to manual MAP processing with several single point runs and insert the crater floor into the otherwise fine AS result. It looks like these captures with high frequency seeing oscillations and prominent noise are a very hard nut to crack. A bit surprising to me since I always have been amazed how good AS is tracking alignment points on almost no contrast in the footage.

Cheers, Oliver

finally some lunar imaging again. The night of April 23rd started with decent seeing at dusk with high frequency oscillation that made focussing tricky but an overall quite stable image. Unfortunately it worsened substantially during my imaging session but I managed to grab some AVIs. Seeing peaked during my Copernicus (again ) capture, here the result:

Click image for full version with details

880 frames have been stacked in AVIStack, wavelet sharpening in Registax and postprocessing in PS. Although the moon was “only” 45° high in the skies this is my best Copernicus image so far. I wasn’t too sure about the optical quality of my C11 but the last weeks showed it’s potential – give me some very good seeing to bring it to the limits
I also imaged Plato and Pitatus during this session but the processing of those AVIs is very tricky. The high frequency of the oscillation combined with the prominent noise due to high gain settings in low contrast regions is fooling the alignment point tracking of all programs I tried so far. The lava floors of both craters are completely washed out in the results obtained so far. I tried Registax 5.1 today without success, currently AVIStack is crunching on the data with some alternative settings…

Cheers, Oliver

Emil Kraaikamp release the first public version of his stacking tool AutoStakkert yesterday. I tried the tool with my Mars captures from April 10th. The results are a tad better than those obtained before, the contrast in the red and green channel images is noticeably higher. Quite impressing since I used the tool for the very first time. The GUI is clean and pretty self explaining and I like the functionalities: All you need to stack planetary images (without multipoint alignment) is there, the user is not bothered with things not useful.
Here the result:

Excellent tool,thanks Emil!

Cheers, Oliver

finally some decent seeing. Skies have been clear on the evening of April 10th so I set up the already cooled C11 at dusk. Contrary to the forecast the seeing looked quite good this time during collimation of the scope and some quick glances at Mars. Just after I fired up the laptop and camera clouds rolled in and obscured the only 8.5″ measuring Mars. Waiting a while was rewarded by clear views again. The session was interrupted several times by clouds but later the skies stayed finally clear. I started to image Mars with a 2.5x Powermate delivering true f/25 with the C11 and tried the Meade #140 2x barlow later delivering a longer effective focal length (!) than the Powermate behind the motor-focusser and filterwheel since it’s not telecentric like the Powermate.
Processing the first set of RGB captures shows that my estimation of the seeing was quite right, results are better than those of April 6th, no artefacts beside the diffraction artefacts at the bright limb.
I slewed over to Saturn after imaging Mars but some preliminary results aren’t on par at all with the Mars material. Maybe seeing degraded (again), maybe the lower altitude of Saturn was quite critical this evening. The main benefit for the Mars captures compared to Saturn should have been the much shorter integration times freezing the seeing. The Mars AVIs show only a single very good frame surrounded by much more blurred ones from time to time.
Here the first Mars result, not too shabby for 8.5″. More to come…

Cheers, Oliver

the night of April 6th looked promising, skies perfectly clear and the seeing forrecast was excellent. I set the C11 up at dusk, collimating the scope at a star showed only mediocre to fair seeing. I started imaging the only 8.8″ measuring Mars after a short visual glance at Mercury and Venus low above the horizon. Seeing was quite unsteady, Mars jumped a lot with a high frequency but there seemed to be very short sharp moments inbetween. Seeing deteriorated constantly over the session – maybe due to the quickly falling temperatures – and quite strong winds arose later and blew the planet of the CCD quite often.
I originally planned to image Saturn after midnight but gave up the plan and gave it a try after Mars but gave up after only two AVIs due to seeing and the winds constantly blowing Saturn out of the capture window…
I was quite surprised when I processed the Mars AVIs of that night: Imaging with short integration times resulted in quite sharp frames in the AVIs packed between many blurred ones. Olympus Mons and the Tharsis Vulcanoes are visible in all channels, there’s nice dust over the Tharsis planes at the morning terminator.
The subsequent Mars AVIs are yet to be processed but some quick processings show that they are not on par with the first ones. The Saturn AVIs are not really worth spending time with them…

Cheers, Oliver

Cheers, Oliver

Click for full version

The RG-RGB version shown her features 70%R/30%G as luminance, oddly enough the differences to the plain RGB version are marginal. I tried to use an orange filter to shoot a luminance-channel with shorter integration times but the seeing distorted the image observably more than using the narrowband R filter. The advantage of 1/30s vs. 1/23s didn’t pay off, the orange results are worse than R results indicating the quality of seeing …
The north polar regions shows an interesting blue-grey-turquoise tint, it should be interesting to watch as the planet tilts  further.

Cheers, Oliver

Click for framed version with detailed information

The result is not too shabby regarding the low altitude and the capture circumstances.
I’m currently trying alternative sharpening functions beside the good old Registax wavelets and obtained best results here using the iterative gauss sharpening from Fitswork.
Ok, Saturn season has started and I’m looking forward to less frosty imaging sessions that might yield in some coloured images

Cheers, Oliver

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