Wesley's Tool-Box

Venus keeps coming closer to the Earth, and it's getting visually larger from here. But since it's in the inner orbit, the crescent is getting thinner as well. Take a look at how it looked like two weeks ago and four weeks ago to see what I mean. I'll be keeping track of the planet regularly as it keeps coming closer. It'll be closest to the Earth almost exactly six weeks from now (January 11, 2014).

Settings: Canon SX50 HS - 1200mm (2x enlarged) - ISO 80 - 1/250s - f/6.5
Filters: Baader M&S applied
Time: 2013-11-30 17:47 KST
Location: Suwon, Korea
17 photos stacked with RegiStax 6.1.0.8

I've risked the streaking and went with lower ISO and longer exposure for today's comet C/2013 R1 Lovejoy photo. I've experimented with the micro-adjustment head (Longperng TP98AR) that finally arrived late last night after much delay to see if that would help reduce the streaking, but manual compensation proved to be quite difficult. So, after about an hour of fiddling I ended up taking simple long exposure photos just before the Sun came up.

As a note, I waited for another pass of Tiangong-1 half about twenty minutes later, but either the calculations were off or it was too dim (it was supposed to be around magnitude 1) against the brightening morning sky to be seen.

Settings: SX50 HS - 243mm - ISO 800 - 15s - f/5.6
Time: 2013-11-26 06:26 - 06:29 KST
Location: Suwon, Korea
7 photos stacked with RegiStax 6.1.0.8

While I made an unsuccessful attempt to photograph Tiangong-1 space station transit the Sun, I noticed some big sunspots. Sunspots like these cause solar flares, which have been prevalent in the recent months. This particular group of sunspots shown here is called AR 11899, of which the biggest one is casually referred to as "Sunspot 1899". It's about 4 times the size of the Earth. If you click the picture for the full look of the Sun, you can also spot AR 11903 near the middle.

Settings: 1200mm - ISO 250 - 1/1000s - f/6.5
Time: 2013-11-23 13:22 KST
Location: Seoul, Korea
10 photos stacked with RegiStax 6.1.0.8

I tried the Baader Moon & Skyglow filter early this morning to photograph comet C/2013 R1 Lovejoy with my Canon SX50 HS as I mentioned yesterday. It has some interesting effects to the photos.

It does tone down the white noise as intended, but the background turns from black to dark blue. The tail doesn't really become more bright because it's a filter that blocks certain wavelengths, not some sort of a booster. But due to slightly lower noise it's easier to make it more visible with post-processing.

For reference, the bottommost star in the cropped photo above is HR 4572 (HD 103799; HIP 58287), a 6.6 magnitude star in Ursa Major.

Settings: 243mm - ISO 1600 - 6s - f/5.6
Time: 2013-11-21 05:32 - 05:36 KST
Location: Suwon, Korea
15 photos stacked with RegiStax 6.1.0.8

A picture of a comet does not seem complete without a tail, and this was not apparent in my first attempt. A long-exposure photo is needed to bring this feature out, but three problems get in the way. One, stars move, so unless I have an expensive tracker installed, I would get streaks instead of dots, especially at high zoom. Two, Canon SX50 HS limits maximum exposure to 1 second for any settings beyond ISO 80. Three, light pollution whitens out long exposures.

The camera's limitation would need to be overcome first to determine how much I can push the other two issues. To do this, I ran CHDK on my camera, a hack that provides more features and removes limitations on top of the default firmware. I was able to easily take photos with 1-minute exposure at ISO 6400 with this. Sadly, this would yield a milky, unusable photo caused mainly by light pollution.

I experimented with the zoom and exposure settings, and determined that a 4-second exposure at ISO 2500 and around 10x zoom yielded not too much whitening or streaking of stars, while just about bring the tail of the comet into view. You can glimpse the tail shooting out at 11 o'clock direction. The noise makes it harder to discern it at 100% size, though.

For reference, the bright star at 1 o'clock direction of the comet is 57 Ursa Majoris (HR 4422; HD 99787), a 5.3 magnitude star in Ursa Major.

By the way, I did try to photograph comet ISON (C/2012 S1) with the same method, but the severe light pollution near the horizon basically washed any possible detail away. I should put the Baader Moon & Skyglow filter on next time if it can reduce this. If it works, then maybe I could catch the tail of comet Lovejoy better, although I still don't have much hope for comet ISON.

Settings: 278mm - ISO 2500 - 4s - f/5.6
Time: 2013-11-20 05:01 - 05:02 KST
Location: Suwon, Korea
25 photos stacked with RegiStax 6.1.0.8. Click the photo for 2x size.