Jupiter, current images from June 2017 on...
May 23, 2018. Seeing was poor when I took this image of the transit of Io and its shadow on Jupiter. Taken about 22:48 EDT with my ASI224MC at the f/11 focus of my C14.
May 9, 2018. The extremely unusual combination of no jet stream overhead and clear skies conspired to give me my first decent imaging opportunity with Jupiter so far this year. I captured a total of 26 one minute videos of Jupiter with the C14 and 2x Barlow, Atmospheric dispersion compensator and ASI225MC camera. Here is the derotated stack of the best 25% of the frames of the first 17 videos.
April 23, 2018. This morning I imaged Jupiter between 5:07 and 5:21 taking sixteen 60 sec raw 8-bit videos with the ASI224MC coupled to the C14 with the ZWO atmospheric
dispersion compensator with the lenses from a 2x Shorty Barlow screwed on the front. Effective focal ratio was f/25, I aligned and stacked the best 10% of the frames with
dither/drizzling to recover the color information in Autostakkert5. I sharpened with Registax6, then derotated and stacked all 16 images using WinJupos. This is my first image of this
opposition season. Hope we get no more nor'easters!
July 9 2017. Seeing was projected to be above average this evening, and the jet stream was east of NJ. I turned on the fans at 6pm and opened up the observatory roof at 8pm and began taking video at 8:36 PM EDT. For the next half hour or so I took 60 second videos in rapid succession hoping to catch some good seeing. Was not to be. Seeing remained poor through the whole session. The videos were processed in AS!2 as usual keeping the best 25% of the frames and sharpening in Registax6. WinJUPOS was then used to derotate and stack all 31 images, followed by wavelet sharpening again. The result is shown at the left.
The images were also assembled into an animated GIF which is shown below. Note seeing getting worse near the end of the animation as Jupiter is getting lower.
July 5, 3017. My TEMP-est fans for the C-11EdgeHD arrived! I installed them today and the weather gave me a fairly crummy chance to try them out. As soon as the sun went below the treeline I opened up the observatory and turned on the fans. I began imaging as soon as I could see Jupiter in the finder. That was around 8 pm. Still a lot of blue daylight present and the haze scattered a lot of light, but an eclipse by Io was in progress and Ganymede was pretty close too. Over the course of the next hour I obtained 9 images with only fair seeing and variable haze and had to shut down when clouds came in around 9 pm. I was imaging with the ASI174MC, ADC and the 2x shorty Barlow lens and cell screwed on the front of the ADC. This gives me about f/20. I took 60 sec videos and processed with AS2! and Registax. Result looked a bit jaggy, so I reprocessed using 1.5x drizzling. Results shown below. Note image taken at 00:16:29 UT. I had turned the fans off just before taking it and back on before the next image taken at 00:27:04 UT. Note the ears on Io’s shadow in the image taken with the fan off. Looks like it is doing something.
Compare the image below taken last spring with my recent images. My equipment has not significantly changed, nor my techniques. But the seeing is simply terrible this year.
June 25, 2017. Partly cloudy with clear patches tonight. I opened up the observatory around sunset to allow the telescope to begin equilibrating. The ASI174MC was fitted to the back of my atmospheric dispersion compensator with the lens cell from a 2x shorty Barlow on the front with NIR blocking filter. Starting at 9:19 pm I took a set of six videos of 60 second length. Each video had about 15,400 frames. I aligned and stacked the best 5% from each video with Autostakkert and sharpened with wavelets in Registax. The 6 images were then derotated and stacked and very lightly sharpened to give the image shown at the left.
June 24, 2017.
It was clear with some scattered high mare’s tails. I set up with the ADC with my unscrewed cell of the 2x Shorty Barlow on the front and the ASI174MC behind it. Seeing was maybe a
bit better than last night, and the ADC helped a lot by really getting rid of the color fringes rather than just moving the R or B layer around later in Registax. I got 7 videos of 60
seconds duration and processed in Autostakkert, keeping the best 25% of 21916 frames. After sharpening in Registax I combined all seven to make the animated GIF shown at the
I then derotated and stacked all seven images using WinJUPOS. The annotated result is shown below.
It is certainly more contrasty than the images I have been getting with the 3x Barlow, but how much of that is due to my using the ADC and the seeing being a bit better, it is hard to
June 22, 2017.
It was mostly cloudy with a bit of rain, however, around 10:00 pm, a large clearing showed up overhead and permitted getting six 60 second videos of Jupiter with the ASI174MC, 3x Barlow and C-11EdgeHD. After processing with Autostakkert and Registax, the images were stitched together to make an animated GIF with GIMP.
Jupiter was low and the seeing was poor, but larger surface features, particularly an impressive blue festoon on the N edge of the EZ were visible. This particular patch of blue sky has been around for a while. I believe it is the same one present in the image taken below on June 9.
June 3, 2017. Tonight I did another experiment to test my hypothesis that flow of air through the three vents, 120° apart around the cell of my C11-EdgeHD, during the time that the telescope is thermally equilibrating was the cause of the 120 degrees apart projections on the images of Io and its shadow on May 28 as well as the experiment of June 2. I applied duct tape over all three ov the vents and opened up the observatory, immediately pointed to Jupiter and began imaging with the ASI174MC and 3x Barlow. I took 46 one minute videos, processed them with AS!2 and Regtistax6, stacking only the best 10% of the frames and then assembled all the images into an animated GIF using GIMP. The result is shown below. Note that in spite of the poor seeing (essentially the same as I had on May 28), the image of Ganymede in the lower right and the images of Io and its shadow on the right hand side of the NEB lack the ear-like projections, nly showing the expected trailing along the direction of orbital motion. So far, my experiments are consistent with the flow of cooler air into the lower two vents as warmer air flows out the top one.
I am waiting for the delivery of my fan kit from Deep Space Products and attempting to decide which of the three vents to place the fans. I will get one intake and one exhaust fan. One vent remains passive. At this point I am thinking I should put the exhaust fan on the top vent (as seen from the normal storage position with the telescope pointing due south with the tube horizontal) and the intake fan on one of the bottom vents. That should speed the natural process of warm air exiting the top and ambient (cooler) air entering the bottom. Perhaps Deep Space Products has a recommendation. I will do another experiment when they are installed to see if they help speed the equilibration process.
June 2, 2017. I went out to the observatory tonight, around 9:25 PM and opened up the foldoff roof in observatory #1 housing the CPC-1100EdgeHD and slewed the telescope up to Jupiter. Over the next couple of hours I obtained a set of videos of both Io and Jupiter to see if the strange tube currents that put "ears" on my images of the Io transit during the session last Saturday evening. It is interesting that my first image of Io obtained at 1:31 UT has less flare than the second one obtained 11 minutes later. This suggests that the tube currents responsible for the flare take a while to develop after changing the elevation of the OTA. The last two images show noticeably less flaring than the previous ones obtained over an hour earlier. There is still some flare in the last one, however. Note that the first Jupiter image obtained at 1:44 UT is considerably poorer in quality than the last two obtained after the hour cool down. Seeing was still bad though.