Sunday, 29 September 2013

Double Stacked CaK Disk - 29th September

My newly constructed double stacked CaK filter is showing itself as a keeper.  Compared to a single stack CaK unit the plage is much brighter compared to the background disk and super granulation is much more evident and apparent over the entire disk.  More interestingly is that proms are much more apparent than in the single stack filter.  Today a surge prom in the 2 o'clock position was easily see, even in this image taken with the 40mm at f20.  There are tantalising hints of the spicule layer also being visible.  Given that this shot  was taken in poor seeing conditions with a low altitude sun, it does bode for even better results when conditions are ideal.  There is still work to do; a 'ghost' is visible superimposed on the right hand side of the disk, but this should be relatively easy to either remove or throw out of the field of view.  In short, i'm really pleased with this filter, I just wish I had got it 6 months earlier this year!