Seagull Nebula
The same night I imaged the IC 2177, SH2-296 [nebula in Mon] Seagull Nebula, Sirály-köd, Sharpless 296, SH2-296 ø120′ [wiki] [simbad] 200mm, gathering 10x195sec at f/4 ISO 3200 with the Canon 1100D mod, Canon EF 200mm f/2.8 L II USM at f/x, HEQ5, using the IDAS LPS D2 clip in filter. For this one I also used my starheal.
California nebula
I managed to dial down the chromatic problems (astigmatism?) of my Canon EF 200mm f/2.8 L II USM, by adjusting the lens’s mount, but it’s still bordering garbage for astrophotography’s needs.
I imaged NGC 1499, SH2-220 [nebula in Per] California nebula ø160′ [wiki] [simbad] 200mm, 400mm on 2018-11-10, with the usual wide field rig, Canon 1100D mod, Canon EF 200mm f/2.8 L II USM at f/4.5, HEQ5, acquiring 21×90 sec of light at ISO 3200. An extra is the IDAS LPS D2 clip in filter.
I like horizontal extensions :)
I like stuff that’s standard, modular, dumb, fault tolerant and degrades gracefully. The mount, the camera, the heating, the guiding — these all have different priorities, different needs and complexities. This is why I chose to use the 12V 7.2Ah standard UPS batteries, many of them, in separate circuits. This setup, obvious from the way the charging is solved, is for occasional one night sessions, not continuous deployment.
One circuit is for the mount. I put one or more batteries in parallel, or more like max(): the batteries are isolated from each other through diodes.
My Canon 1100D (modified) does work from a USB phone charger, but it has its own 12V battery. It works well, non stop all night, from a single battery, without depleting it. A fellow amateur astronomer has already asked me to make him a similar wonder-box :D See details.
The DSLR was the last item that a voltage other than the one provided by the standard 12V batteries. Its own batteries meant special care, special costs, and thankfully that is over, once and for all. (tovább…)
UPS battery powered Canon
I work with a modified Canon 1100D camera, which uses the LP-E10 battery. The battery pack has the tiny nominal capacity of 860 mAh (Canon original), 950 mAh (some copy) or 850 mAh (some other copy), equalling 6-7 Wh. During a long photo session, and depending on the temperature, 2-3 batteries may go out from fully charged to blinking red, interrupting the photo session, and – on the long term – mean further replacement batteries. For comparison, a UPS battery holds at around 80Wh, at least on paper.
While the form factor is proprietary, meaning vendor (or at least product) lock in, the batteries are dumb. Luckily. Luckily the battery pack has no digital identification mechanism, so some crocodile clips are enough to replace them. No need to disassemble one to use the chip or something like that. So I got to work.
Saturn’s moons
I imaged the moons of Saturn with a difference of about an hour. They moved :)
This is the first light of the ASI 120 MM camera, the most recent addition to my instruments. The Moon below is a mosaic made with the N 150/750 and through a Barlow lens.
The same file, two different processings. Raw data obtained with N 150/750, barlow, ADC, tubes, ASI 224 MC, 2% of 40k frames.
Some Saturn images with the N 150/750 + ASI 224 MC gear.
2018.09.12. 20 34 07
2018.09.12. 20 34 07
2018.09.12. 20 34 07
2018.09.14. 20 42 08
2018.09.14. 20 22 49
2018.09.14. 20 22 49
2018.09.14. 20 22 49
2018.09.16. 17 13 37Z
Neptune and Triton, I think
Neptune is not that hard to find, in theory. Add light blinding pollution, a not so accurate polar alignment and some passing clouds, and it becomes a PITA.
The other thing is, that IF the object I photographed is indeed Neptune AND Triton, the moon is off compared to Stellarium. I intentionally photographed a reference star too, so I could put it on a map. However, the map itself is the DSS and some stars may have just moved away.
The gear: N 150/750, 2x Barlow and empty extension tubes, the ASI 224 MC camera, on the HEQ5 mount, in the city. 2018-09-11 22:26Z, ie 2018-09-12 1:26 local time.
It’s been twenty years since one of my first entries in my log, and exactly twenty since the first (more like one of the first) Jupiter observation. Living at the very margin of my home town, with a full horizon east-south-west, and very poor public illumination characteristic of the post-communist era, I had a decent view of the night sky. I remember how I „discovered” Jupiter as an odd star that’s not supposed to be there in the constellation, during the dawn. As time passed the star has risen, so I was able to observe its… satellites, so it was Jupiter. And this is the entry I made twenty years ago. However, checking it out now in Stellarium, I see that I missed Saturn. Jupiter’s satellites’ positions are ambiguous, it could be 21:45 or anytime till midnidght since the bino I used (12×25) most likely didn’t show Io that’s been close to Jupiter during those hours. The Moon came later, towards midnight, hence the datetime of the entry.
1998-09-10, clear sky, at about midnight: The first luminous one is Jupiter, and I’ve seen three of its satellites, and also some craters on the Moon.
1998.09.10. Csillagnapló-részlet
