Quark Single Stack Double Stack Comparison - 24th January

I have to stress this comparison image was taken in far from ideal conditions, the sky was particularly hazy with poor seeing, and, given we are in january the low altitude of the sun.  However it does show very well the effect of double stacking - the double limb feature disappears, filaments are more pronounced and sunspots become more ill defined as photospheric leakage is reduced.  This is a comparison I want to try again later in the year in better conditions.  The Quark was double stacked by simply putting a PST etalon in the Quarks eyepiece holder.  Taken with the 70mm f6, 0.5x reducer and Daystar Quark with the Imaging Source DMK31 camera.