FAIL Observations, Tuesday 16 October 2012

Location: Home, outside back door
Conditions: Seeing good, clear but gathering cloud.
Equipment: Skywatcher 130, 25mm eyepiece.
Highlights: none

A mixed evening. Caught up earlier on writing up my logs from Oman so that’s a WIN.
However my observations with the scope as a FAIL. Didn’t find any of the targets I was looking for, although it was useful as starhopping practice. These notes are for completeness and for potential future comparison for when I do manage to observe these targets.
Clear skies outside with some cloud so I set up outside the back door. My plan was to have a crack at he September Sky at Night magazine Deep Sky Tour around Cygnus. Cygnus was to the west, close to the zenith just above the fir trees. That’s why I set up there. Tried for both the Pelican Nebula, IC5070, and North American Nebula with no joy. Below is the notes I put into SkySafari+ as I was working on them.

Pelican Nebula – IC 5070 Bright Nebula in Cygnus 16 Oct 2012 21:15
Did not find. From Sept S@N DST. Located the area between sars Cyg 56 and 57 by starhopping from Deneb. No sign of nebula though. Seeing is good tonight. Moved away and came back to confirm my hop and tried again to discern the thicker patch between 56 and 57. FAIL

North America Nebula – NGC 7000 Bright Nebula in Cygnus 16 Oct 2012 21:29
Another DNF from Sept S@N DST. I fancy i can make out some nebulosity but probably not. This is a big spread out nebula so using 25mm eyepiece. In the right area. Have referred to star charts several times to confirm. Too much grey and not enough black in sky. Tried to use Gulf of Mexico and Mexico areas as recognisable features and again FAIL

I’m about to give up on the Sky at Night Sept 2012 Deep Sky Tour. I just don’t think it’s possible in these skies.

Dubai Observations – Friday 28 September 2012

Back from a holiday in Dubai and Oman. I had a great time and most evenings I managed to get some stargazing in while there. I’ve a bundle of notes and sketches scribbled on hotel notepads. Over the next few days I’ll be writing my observations up and posting them here. I took my Celestron Skymaster 15×50 binoculars with me and a tripod so observing was with those or naked eye.

Location: Dubai, Souq Al-Bahhar, Mall of the Emirates hotel.
Weather: Hot.
Equipment: Naked eye, Celestron Skymaster 15×50 binoculars
Highlights: Summer Triangle, Vega, rotation, moon, Jupiter, Venus

23:00 Sitting eating our evening meal at the Souq Al-Bahhar opposite the Burj Khalifa in Dubai. Just watched the Dubai Fountain show in front of a lit up Burj. With the naked eye to the left of the Burj I can see a star. It must be a bright one as there’s a huge amount of light pollution around here and it’s not easy to see any. A quick check on Sky Safari on my iPhone confirms my suspicion that it’s Vega.
So, that fainter one I can just make out to the left of it must be Altair, and so the one above must be Deneb. Once again I’ve found my familiar signpost – the Summer Triangle.
But now the strange thing. It’s all rotated about 30° clockwise to what I’ve become used to. I need to work out and understand why that is. I was used to Vega being at the top of the triangle through the Summer back home. Here it’s Deneb. Is that because we’re at a lower latitude or is it just because it’s a few months on from when I was observing it back home? I haven’t thought it through yet but that probably makes sense as we’re about 30° further south at 24°N (Home is 52°N.)

Incidentally, I was looking at the moon earlier, through the binoculars through the hotel window, while A was getting ready to go out to eat. It was almost full. Below Tycho I could make out some edges of craters along the terminator.
I was noticing that curve of the terminator is at a different angle to back home. I think this is for a different reason though. I seem to recall listening to an Astronomy Cast podcast that explained that.We were out by the Creek just before sunset, on the roof of the Sheikh Saeed Al Maktoum House. The setting Sun was low, perhaps 15°, to West. Meanwhile the Moon was just becoming visible to the east, at about the same elevation.

Anyway, meanwhile back at Burj Khalifa and the Dubai Fountains. We left through the Palace Old Town hotel and whilst waiting for a taxi spotted Jupiter. It’s the brightest thing in this sky apart from the Moon, the planes, the crazy buildings….

Next morning was an early start to get a flight to Oman. From the taxi to the airport I caught a brief glipse (again naked eye) of Venus just before dawn and saw the Sun rise between the buildings to the East of Sheik Zayed Road.

Summer Triangle Widefield Imaging – First Attempt

At mentioned in my last post, I ended up with 263 frames of the Summer Triangle. I thought I’d have a go at processing one of these to see if I could get more detail out.

So here’s my starting image.

I hadn’t realised quite how bad my light pollution was until I saw this.
It’s a 30 second exposure, sunlight white balance at ISO400 taken on a Canon EOS400D with a Sigma zoom set at it’s widest 18mm focal length.
faintest stars you can see here are about magnitude 4.
I then tweaked it a bit in photoshop, adjusting levels to bring out fainter stars up to about magnitude 7. I removed the colour cast as best I could, although I think I went a bit too at as it’s quite blue now.

Now I know this is far from perfect. It’s a first attempt and I can see quite a few problems.
Stars aren’t quite in focus. I’d focused manually and it’s difficult to know in the dark through the camera eyepiece.
Next time I’ll lock the mirror up to prevent that causing a bit of shake.
Exposure is only 30 seconds but I don’t think I can do longer without the stars blurring with motion. I could, if I put the camera on the telescope’s mount. There is a piggy back mounting screw.
I think I need to really up the ISO, perhaps up to 1600 to captured the fainter stars. I’d held back because I thought I’d end up overexposed with all the light pollution. I think though, that I can fix that with levels in processing.
I need to investigate stacking multiple images too, as that seems to be how many people do it.

Finally I annotated the final image in Skitch on the iPad to identify the various constellations and stars. That was an fun and educational thing to do. I hadn’t noticed the small constellation Delphinus creeping in just below Cygnus for instance, and on zooming in and around the shot, I also noticed Collinder 399, Brocchi’s Cluster aka the Coathanger sneaking in.