Hello got a couple of images ot Comet Lemmon Last night-Going from ISO-800- to ISO-1600 -and In camera raw adjusting the Exposure slider up-Gives a bit more detail in the tail -Tracking on the comet and not guiding probably bring the detail undone a Bit -Exposure-512 seconds at ISO-1600-90mm Williams optics 6.9F/L -Apo -0.8 W/o-field flattener reducer.primefocus to Canon 450d modded.-Time-21.25pm-05/03/2013.