Monday 14 April 2014

CaK Full Disk 14th April

Lots to see again on our star in CaK wavelengths:  this image was taken with the 80mm frac running at ~700mm focal length, this disk is a mosaic of 6 individual panes with the homebrew caK filter and Beloptik tri-band ERF.  I'm pleased with this setup as when the seeing is good is giving me considerably more detail than my usual 40mm full disk setup.  There's lots of contrast with this setup, mainly due to the fact it is stepped down from the original 100mm aperture, and while spherical aberration is good at 100mm it can only be better stepped down to 80mm.  There's a ghost on this image as I was messing around with the tilt of the filter elements, but should be able to throw this; guess i'll find out whether it was successful when I have a go at imaging wednesdays sun!