[Shiraz (Ray)]

Hi
Have been waiting many weeks for some clear sky to test out an ASH dispersion corrector against the sinking Saturn. I had a little bit of calibration data from earlier testing and finally worked out an efficient procedure for aligning the thing on a Newtonian scope - and got a big enough hole in the clouds on the 26th to take a corrected LRGB sequence. Although there was not enough clear sky to take a before and after sequence, the corrector clearly made a big difference to the luminance data through the 60kt jetstream edge.

Posted the RGB stack and the LRGB stack. RG at 30Hz, B at 15Hz and L at 60Hz - 300mm Newtonian, 5x Powermate, TIS618 and Astronomik filters. Nothing wonderful as images go due to the jetstream, but the improvement with the dispersion corrected luminance is striking. At this low down, the luminance would normally be so smeared by dispersion that it would be unusable. This little gadget cost an arm and a leg - almost as much as my scope, but it works. now to get some good seeing and test it properly - should help with G and B on Jupiter as well.

edit: I have no relationship of any type with ASH

thanks for looking. regards Ray