AstroPhotography Tonight is very pleased to present the work of Sean Davies from Moose Factory, Ontario. Sean captured a series of spectacular images of the rare Venus transit that occurred on June 5th, 2012. The transit was the result of the planet Venus passing between the Earth and Sun. The last time we were treated to this event was in 2004 but it won’t happen again until 2117!
Below is Sean’s account of his experience with imaging the transit. Visit Sean’s flickr site for the full set of images and details.
I observed the transit in Moose Factory last week and spent some time preparing for this event. We had rough weather for 2-3 weeks prior to the day of the transit, then about 2 days leading up to the event, the skies cleared and steadied.
Moose Factory is a very small island in a remote area near James Bay, and has it advantages in that the night sky frequently enjoys very good seeing conditions. Aurora are also frequently seen here due to it’s latitude (51 degrees north).
I’m fortunate enough to have all three optical systems available to an amateur to observe the sun; that being an ED refractor with a Herschel wedge, and 60 mm h-alpha/CaK solarscopes from Lunt.
Planning is crucial for this sort of event, and would involve “juggling” optical tubes during the transit. Fortunately the transit lasted 4 hours so minor adjustments were easily accomplished.
I had discovered that my color imager (Chameleon) from Point Grey had an IR blocking window several weeks earlier prior to this event. This resulted in sensitivity issues in the hydrogen alpha wavelength. Fortunately a request I made from Technical Support at Point Grey Research corrected the problem – they sent a clear optical window absolutely free of charge.
The replacement of the IR filter greatly improved the sensitivity CCD sensor, which can be seen in the h-alpha images.
The software used was an imaging capture software from Point Grey Research (flycap2). post processing was done with Registax 6.0 and GIMP 2.8.
There was not one image that stood out over the other, all were spectacular in my opinion, so the concept of a “mosaic” or collection of images grouped together in a visual composition seemed to be the best way to capture all of the best elements of this rare astronomical event.
I went to work and re-sized the images, keeping the most dramatic image (the entry of Venus across the limb of the sun) as the main image sequence of the composition.
Some technical information was then compiled to “educate” through the images, which included a graphical reference about the transit from a NASA site. I thought the reference from NASA also added and made complete the final composition.
Overall I am quite satisfied with the final composition.
Moose Factory, Ontario