Wesley's Tool-Box

Mars comes very close to Earth every 780 days or so. This happened again last night - distance between Mars and Earth was 0.618 AU. The last time Mars made an approach closer than this was back in December 19, 2007, when it was 0.589 AU. At these distances, Mars is 15 arc seconds big, which registers as 10 pixels wide on my SX50 HS at maximum optical zoom. Until the next approaches on May 31, 2016, or July 31, 2018, this is about as big as it gets for the camera. Still, using both the 2x digital teleconverter and RegiStax stacking, I was able to get a clearer image of the planet from the multiple photos.

Meanwhile, a full moon was right next to Mars yesterday. This created a good opportunity to take both the Moon and Mars in the same photo. Full moon is quite bright, but Mars was also shining at its peak (-1.4 magnitude), so it was holding on its own. Interestingly, a lunar eclipse is also supposed to happen today, dimming the Moon so that Mars would be easier to see. But it happens during the day here, while both the Moon and Mars are below the horizon. So that's no go for me.

The lunar eclipse that is visible in my country would happen on the early evening of October 8, 2014, starting as the Moon rises from the horizon. At that time, the faint Uranus (5.7 magnitude) would be next to the Moon. I wonder if the eclipsed Moon would be dim enough for me to see the planet, weather and location permitting.

Device: Canon SX50 HS
Filters: None
Location: Suwon, Korea

Main Image
Settings: 351mm (reduced to 20%) - ISO 80 - 1/80s - f/5.6
Time: 2014-04-14 23:34 KST

Inset
Settings: 1200mm (w/ 2x Digital TC) - ISO 80 - 1/200s - f/6.5
Time: 2014-04-14 23:23 KST
41 photos stacked with RegiStax 6.1.0.8

Planets shine bright even under a washed-out city sky, so I've gotten around to photographing them often. But it has only recently come to my mind that maybe I should take many of them in a single night and see how different the apparent sizes are at the (almost) same time. Last night was cloud-free, so I got around to actually carry it out.

So here's Jupiter, Saturn, and Mars. Venus was considered, but the nearby buildings blocked the view and I wasn't dressed to venture outside at the time. I did photograph the Moon while it was close to Jupiter. But it's too big to display it along with the planets, so that'll be up on another post.

Jupiter is the biggest, as expected, and it'd always be the biggest round planetary disc found in the Earth's sky. Currently, Mars looks slightly smaller than Saturn without its rings. When it makes a close approach to Earth, though, it can look bigger than Saturn.

Device: Canon SX50 HS
Settings: 1200mm (2x enlarged) - f/6.5
Filters: None
Time: in KST
Location: Suwon, Korea
Stacked with RegiStax 6.1.0.8

Jupiter: 2014-03-10 23:38, ISO 160 - 1/80s, 17 photos
Saturn: 2014-03-11 05:40, ISO 160 - 1/40s, 15 photos
Mars: 2014-03-11 05:52, ISO 80 - 1/160s, 15 photos

Just after taking photos of Saturn last Thursday, I could see that Mars was right next to it, so I decided to point my camera at it, as well. This would be the first time I took photographs of Mars.

Closest approach of Mars to Earth for this year would happen in about a month (April 14), but it wouldn't be quite as close as some of the years, so it would look rather small - it would be 60% that of August 27, 2003 and 62% that of July 31, 2018. Still, I'll try to take some photos when that happens.

Device: Canon SX50 HS
Settings: 1200mm (2x enlarged) - ISO 80 - 1/125s - f/6.5
Filters: None
Time: 2014-03-06 06:32 KST
Location: Suwon, Korea
14 photos stacked with RegiStax 6.1.0.8

Saturn is the first planet I photographed with my Canon SX50 HS back in June 2013. The rings made it clear that I was shooting a planet, and served as a great first target. Since then, I got around to taking photos of other planets, satellites (natural and artificial), and stars.

In the meantime, Saturn was beginning to set too early in the sky, so I was no longer able to take new photos of the planet for several months. Now it rises in the middle of the night, up in the sky until dawn. I woke up this morning slightly early, and saw Saturn weakly shining against the brightening southern sky. I quickly set up my camera and got some shots.

The rings are still quite nicely visible around the planet. Compared to last year, Saturn seems to be leaning a bit more, making the rings look more like ears.

Device: Canon SX50 HS
Settings: 1200mm (2x enlarged) - ISO 160 - 1/30s - f/6.5
Filters: None
Time: 2014-03-06 06:27 KST
Location: Suwon, Korea
29 photos stacked with RegiStax 6.1.0.8

I've been using my Canon SX50 HS superzoom camera almost exclusively as an astrophotography machine since middle of last year. The 50x zoom is enough to make many of the planets show up as disks rather than spots, so it feels like having a compact telescope with integrated camera. At full zoom, the settings are at 1200mm, f/6.5, and ISO is set to 80 for best quality. Jupiter shots are usually taken at around 1/100 to 1/250s shutter speed (it was 1/160s here), while bright Venus shots can go up to 1/1000s.

Of course, even such massive zoom by camera standards don't make the planetary disk very big. two biggest examples are Jupiter, which goes up to about 32 pixels wide, and Venus, about 41 pixels wide. So getting good details from a single shot is difficult. I have to apply some techniques used by the astrophotography community to enhance the results.

The big helper is undoubtedly RegiStax, which does both stacking and wavelet processing. The stacking averages the multiple photos of the same object, which preserves the details while reducing noise. RegiStax doesn't simply stack the photos, though. They are aligned and only the ones with good quality are picked out for stacking, which improves the quality even further.

In this Jupiter example, I took 131 photos of the planet, out of which 41 of them were picked by RegiStax for stacking. Compared to the grainy photos originally taken by the camera, the stacked image is much more cleaner and smoother. But the cloud features are soft and hard to make out. This is where wavelet processing comes in.

Wavelet processing can be used to amplify the little details in the photos and make them stand out. After making some adjustments on the strength of each wavelet layers, the cloud features became more distinct. There's a ripple in the lower part, and magnifying the processed photo by 200% shows that this is the Great Red Spot (GRS). Rotating the photo (by 54 degrees in this case) makes the planet look "upright".

And this is how I currently process the planetary photos.

Settings: 1200mm - ISO 80 - 1/160s - f/6.5
Time: 2014-01-19 02:57 KST
Location: Suwon, Korea