Photos from the South

starfinder · Post by **starfinder** » Fri Apr 10, 2009 12:24 am

Seeing some of Remus' and Sam Lee's photos from Victoria, I dug up and had a relook at some of the photos which I took two years ago at the South Pacific Star Party in New South Wales, April 2007.

I had actually almost forgotten about them. Here are a few.

All were taken with a Canon 350D on a photo-tripod with a Sigma 17-70mm lens at 17mm.

This self-portrait was at f/2.8, ISO 1600, 20 seconds, self-timer. Unprocessed except for re-sizing down.

This is of the Crux-Carina region with the two Magellanic clouds.
Taking Crux and the SMC/LMC as a triangle, the south celestial pole is roughly in the centre of this triangle.

30 seconds, ISO 1600, f/2.8. I think it shows slight chromatic aberration, so perhaps I should have stopped the lens down to f/4. Unprocessed except for re-sizing down.

And here is one of the Milky Way in the background, with a silhouette of a giant 25". The views through that one were amazing! Centaurus A was like a BK Whopper on a table in front of you.

20 seconds, ISO 1600, f/2.8. Unprocessed except for re-sizing down.

I particularly like wide-field photos. Now if only I had an AstroTrac with me then and could take 10 min exposures.

Hmmm....

wintertriangle22 · Post by **wintertriangle22** » Sun Apr 12, 2009 5:19 pm

Nice photos of the magellanic clouds & coal sack

Post by **rcj** » Tue Apr 14, 2009 12:22 pm

Very nice Gavin! Liked the one with the guy next to the dob....

Sam Lee · Post by **Sam Lee** » Tue Apr 14, 2009 5:00 pm

Like the first one .. that looks like a guy with a tripod mounted bino ?

starfinder · Post by **starfinder** » Tue Apr 14, 2009 10:03 pm

Thanks for all the comments!

Yes, the first one is of me looking through a 20x80mm bino mounted on a small alt-azi fork mount which in turn was mounted on a photo tripod. The camera which took this photo was on another tripod set on self-timer for a 20s exposure. I was wearing a jacket and hood, that's why the figure looks a bit plump!

I think this photo and the one with the guy next to the Dob capture the essence and mood of star gazing. Looking in quiet wonder at the celestial heavens in tranquility and calm. That to me is the main attraction of astronomy.

To think of it, the Coal Sack and the Magellanic Clouds are a good complement of dark and light patches. Hmmm... That I think was the first time I had a good view of the Clouds.

What amazed me then was seeing a celestial object (I think it was the SMC) setting and disappearing below the tree line in the early evening and then seeing it reappear and rising again a few hours later in the same night. How strange, for in our tropical location (Singapore/Johor) once an object sets it sets for good for the night. And the concept of circumpolar objects is likewise virually non-existent here.

Conversely however, when I once told an experienced amateur in Australia that we can theoretically see the entire celestial sphere from Singapore, he was quite taken aback at first before realising that it was correct. Now that concept must be strange to those who live in the higher latitudes in the north and south.

starfinder · Post by **starfinder** » Fri Apr 17, 2009 12:40 am

I have dug up one more photo taken during that night 2 years ago.

This one is of the region of the Pointers, Crux and Eta Carinae: the classic Southern photo.

Imaging details:
-Canon EOS350D with a Sigma 17-70mm lens at 17mm, f/2.8, ISO1600, a single 15-second exposure.
-Mounted on a photo tripod, i.e. untracked.

I did quite a lot of processing for the image below today using Photoshop Elements 2.0, as follows:

- Dark frame subtracted (method from: http://www.covingtoninnovations.com/dslr/Combining.html)

- Brightness and contrast adjustment using Levels.

- Color adjustments using Hue/Saturation on Red, Blue, Yellow, Green. Basically to increase Blue saturation throughout, but reduce saturation of all other colours except to increase yellow isolated around Gamma-Crucis and red around Eta Carinae. Hmmm.... quite a bit of manipulation there. Is that considered proper? I think it's probably ok as long as saturation is changed but not to "add" in colours.

- Cropped, resized, and then converted to JPEG for uploading to Picoodle.

I think it's quite amazing what can be achieved with a single 15-second exposure with digital SLRs and then processed with software. I remember in the old days of print film, 15 seconds or even a minute would have gotten you nearly nothing. I had come back from Telok Sari and developed a roll of 36: nearly all shots except a few were nearly blank.

Meng Lee · Post by **Meng Lee** » Fri Apr 17, 2009 1:59 am

Very good, but just note the black clipping.