Hi All,
The image have been processed and I can finally share my experience with the 10.4m
Gran Telescopio Canarias (GranTeCan) and at
STARMUS festival.
As some know, I won STARMUS
astro-photoraphy contest in May and got to spend the week of June 20-25th on Tenerife Island, Canary Islands, Spain at the festival which was out-of-this-world.
I met Neil Armstrong, Buzz Aldrin, Alexei Leonov, Yuri Baturin and Claude Nicollier as well as listened to the presentations by Nobel lauerates - George Smoot and Jack Szostak and other eminent scientsts: SETI Director Jill Tarter, Kip Thorne, Richard Dawkins and Michel Mayor.
More about my STARMUS experience, the new time lapse, 360 degree VR tours and photos are in my
blog
The main prize of the STARMUS astro-photography competition was unbelievable one hour to observe with 10.4m
GranTeCan.
After long deliberations I chose to observe Arp84, a pair of interacting galaxies NGC5394 and NGC5395 (sometimes referred to as "Heron" because of the appearance). They are 162 and 165 million light years away and are considered to have gone through a recent nearly grazing collision.
The main considerations were:
1) Interacting galaxies (because I love to observe them)
2) Fitting into 7.8' FoV of
OSIRIS nicely
3) Not imaged by a professional telescope in colour and detail.
The imaging instrument
OSIRIS has two monochrome detectors with a small gap in the middle. The images were taken with g, r, i and F657 H-Alpha filters. In order to reduce the data from OSIRIS I had to use professional astronomy tools because nothing I tried from the amateur astroimaging software would understand FITS from OSIRIS with two image planes. I found THELIS and installed Linux in a Virtual Machine to properly apply flats, biases and stds. There are no darks with cryogenically cooled OSIRIS.
The first attachment is calibrated and median-combined g,r,i layers. As you may have noticed, there is no blue filter in OSIRIS and I was scratching my head what to do in order to get the colour image. At the festival I met Noel Carboni (from ProDigitalSoftware) and he kindly offered to help with the colour image - the second attachment. The result is quite natural looking colour image with g,r,i mapped as b,g,r and F657 data added to the r channel.
Some more data:
- The primary 10.4m mirror consists of 36 hexagonal segments fully controlled by an active optics control system
- Exposures were 3x30 seconds to overcome the gap in between the detectors.
- Position of the center of the image is (RA, Dec) = (13:58:28, +37:26:42) in the constellation Canes Venatici. Celestial North is up.
- Field of view is 7.58 x 8.27 arc-minutes.
- Image resolution (in the full size 2000x2000 pixel image) is 0.26 arc-seconds per pixel. We used 2x2 binning and the seeing was 0.8 arcsecond.
- The three brightest stars are magnitudes 13.7, 15.2, and 15.4
It was an incredible week at the festival and at the observatory on La Palma.
The time lapse is here (view in full screen with sound):
http://vimeo.com/terrastro/outerspace
Images I took at the observatory on La Palma are also attached.
Cheers,
Alex