Monday, 30 December 2013
Sunday, 29 December 2013
The sun was certainly low in the sky today, and in the crisp air and deep blue sky looked very picturesque. However looking in the wavelength of hydrogen light details on the sun just pop into view that can't be seen in normal light. This shot was taken with the Coronado DS40 at f10 with a DMK31 camera. It's easy to see all the activity is focused in the suns southern hemisphere corresponding to the this dual hemispherical peaking we seem to be having this solar maximum.
About as close as the low sun and turbulent seeing would let me get on a cold frosty winters morning. This image was taken with the triband ERF, DS CaK filter and 70mm frac at f10 with the DMK31 camera. A good result from a setup that shows much promise!
This was the first outing for my new triband ERF from Oliver Smie at Beloptik; I installed it in the dew shield of my 70mm f6 refractor where it was a perfect fit. Using my using rear mounted homemade CaK filter setup the first thing that struck me was how much shorter the exposure time was probably due to the ERFs transmission of 70% compared to the usual 5% of the solar wedge I was using as a filter. Optical quality is spot on, and later in the year I plan to do a more thorough review at the 3 wavelengths it operates at. I'm pretty pleased with this image - even given the smudge at the bottom of the disk is the branch of a foreground tree.
After weeks of unfavourable conditions I was able to end the year on a solar high. After spending the day rebuilding the helical focus assembly on my Coronado SM40 tube assembly I switched the Ha filters for my homemade double stacked CaK filter, seeing was awful first thing on this frosty sunday morning so used a 0.5x focal reducer to try and tame the seeing a bit. It seems to have worked and i'm pretty pleased with this result!
Friday, 27 December 2013
I tried aiming the camera higher in the sky to cut out the foreground horizon, but this made no difference at all; the temperature was well below freezing and the crashing waves a hundred metres to the north of me were throwing mist up into the air at an annoying rate. All the way through this imaging session I used my trusty Canon 350D at iso800, 30 second exposure with a Sigma 10-22mm lens, at 10mm f4 all mounted on my manfrotto tripod. I tried reducing both the exposure and ISO, and while this reduced the brightness of the skyglow it also reduced the brightness of the aurora, which is definitely not what we are trying to achieve.