Saturday, 19 April 2014

Purple Sun - 19th April

I really are liking the level of detail my homebrew CaK filter is pulling out in ultra violet wavelengths, the filaments are borderline visibility as are the proms.  I still have a reflection issue that i'm trying to deal with - i've improved it, but not solved it yet - maybe a UV polariser?  I'm going to try the filter elements in a different order, but keep the spacing of the elements - as this seems to work.  Certainly on the parts of the disk where the ghost is not superimposed there is more detail visible, giving this part of the filter an apparently tighter bandwidth.  If I can sort this out it really should bring the best out of this filter setup!  Today's image was taken with the 40mm at f20, with the DMK31 camera.