In the few days I had the camera I was determined to acquire some astrophotography test shots with the EOS-M camera. Even if it meant getting up at 3am to have some dark sky after moonset. It would have been easier a few days before, but a Pacific storm system had provided several days of overcast with occasional rain. This particular morning was just about perfect, clear skies, decent seeing and no wind to bounce the telescope around.
Astrophoto setup with AT6RC, SBIG STi autoguider and the EOS-M cameraFor testing I used the same setup I often use with my Canon 20Da or 60D. An Astro-Tech 6″ (150mm) Ritchey–Chrétien telescope riding atop a Losmandy G11 mount. A 0.8x focal reducer has T-thread at the rear allowing a Canon EOS lens adapter. To attach the EOS-M I used the Canon M Mount to EOS Mount adapter. An SBIG STi autoguider completes the setup.
The result is an f/7 optical system with 1080mm focal length. This gives a field of view of about 72×48 arc-minutes (1.2 x 0.8 degrees) on the sky when using a camera with an APS-C sensor.
Tomorrow morning, November 26th, will see a very close rendezvous of Venus and Saturn in the dawn. The two will be less than a degree apart, with a separation of only 40 arc-minutes. This will put both planets in the same low power telescopic view. The pair will rise about 04:30HST and be well up, nearly 30° above the horizon, at sunrise.
This is a mismatched pair, with Venus dominating the view at a brilliant -4.0 magnitude. Saturn will be far dimmer at 0.6 magnitude.
DSLR cameras have been the design of choice for professional and serious amateur photographers for over a decade, ever since the era of digital photography began. Big lenses and big sensors made the most of what light was available offering the best possible photographic performance. This performance is a huge jump over what the smaller lenses and sensors of compact cameras offer. A performance gain that makes carrying such a large camera worthwhile.
A DSLR is big because of the demands of the available technology. The swinging mirror directs light into optical viewfinders and phase detection focus sensors. Over the last couple years a new type of camera has appeared, taking advantage of advances in technology to dispense with the bulky swinging mirror design. Fast, high resolution electronic viewfinders and better focus technology allow this transformation. Engineers can create a camera far smaller while keeping the large sensor and interchangeable lens. Better yet, getting the lens closer to the image sensor allows a smaller, lighter, less expensive lens without sacrificing performance. Enter a new paradigm of camera that offers much of the performance of a DSLR in a compact design.
The Canon EOS-M with the 22mm f/2 kit lensAll of the major players have now released their own spin on the mirror-less design. Panasonic and Olympus jointly released compatible designs under the Micro Four-Thirds standard. Sony has released their NEX system and Nikon the Nikon 1 system. A number of lens makers, Zeiss, Tamron, and Sigma now make lenses for these cameras. Canon was the last to release an entry into this new market segment.
Over the coming days, Venus and Saturn will rendezvous in the dawn. Already drawing close, the pair is separated by less than 4° this morning. Close approach will be on the morning of the 26th when the separation will be only 40 arc-minutes. The two will remain close for about a week, the separation having grown to over 4° on the morning of the 30th.
This is a mismatched pair, with Venus dominating the view at a brilliant -4.0 magnitude. Saturn will be far dimmer at 0.6 magnitude.
Mercury is beginning its third and final dawn apparition of the year. Today the planet will be over 10° from the Sun, rising a little further each day until maximum elongation on December 4th. There will be a nice trio with the Moon and Venus around December 11th.
Günther Hasinger
University of Hawai’i Black Holes and the Fate of the Universe
The character and distribution of stellar and supermassive black holes is a fascinating and rapidly changing area of astronomy research. Recently, the W. M. Keck Observatory has confirmed supermassive black holes are in the centers of most nearby galaxies, including our own Milky Way. A tight relationship exists between black hole mass and the properties of their host galaxies. New instrument capabilities, like those planned at Keck, will reveal even more about the nature of black holes and how they play a role in the ongoing evolution of the universe and everything in it.
Looking into the optics of the Keck 2 telescopeTuesday, November 20, 2012
7:00 PM
Gates Performing Arts Center Auditorium
Hawaii Preparatory Academy
65-1692 Kohala Mtn. Rd., Waimea
Seating is limited to first come, first served.
Doors Open at 6:30 PM
Free and Open to the Public
Why are so many things I shoot determined to hide in a crevice. I may be big and noisy, but I just want to take your picture, not eat you. Maybe if I hold the camera upside down, twist the strobe to the side, maybe I can get a decent photo…
Red Swimming Crab (Gonioinfradens paucidentata) in a crevice at 40′ depth, Kaloko
To quote Douglas Adams… “Space is big. You just won’t believe how vastly, hugely, mind-bogglingly big it is.”
We are accustomed to using miles or kilometers when considering distance. These are the distances that we experience in our everyday lives. Driving to work or the supermarket, we do not travel very far compared to the distances faced by those who study the stars. Those wanting to discuss distances beyond our little planet, the distances to the stars and galaxies face a quandary… The universe is just too big, when using these familiar units the number of zeros become impractical and the numbers cease to be convenient, or even understandable. To express distances in the cosmos, astronomers just need a bigger tape measure.
The Andromeda Galaxy, 2.5 million light years awayWhen expressing distances among the stars we turn to the same phenomena we use to observe the stars, starlight itself. We know that light travels fast, covering huge distances very quickly. Light, just another form of electromagnetic energy, is a universal constant across the universe, how far it travels in a given time is a convenient standard by which to measure the universe.
In a few minutes light travels across our solar system, in a few years it can reach the nearby stars. Thus a distance unit that makes sense in astronomy… The light-year, the distance light travels in a single year. With this we have a convenient unit of distance, one that links the concepts of distance and time. A simple bit of math converts the light-year into familiar units… 9.45 trillion kilometers or 5.86 trillion miles.
Today the planet Mercury passes through inferior conjunction, passing between the Sun and the Earth. In a week or so the planet will again be visible in the dawn sky, climbing higher each day. Maximum elongation will occur December 4th.
