Thanks, Larryp and anthony.
My 305 GSO was on a NEQ6-Pro, with sideral speed. Because the comet was very near the south, the polar alignment is well and the short time of exposition, I didn't use guiding by refractor 70 mm Vixen assembled with 305 GSO.
I used DSS to track comet position and stars, and Photoshop.
At the moment of work there were much thin clouds. So much of them, that with 25 mm and 9 mm ocular I only saw the comet with peripheral vision. No success to capture the tail.
It was done in a short time, before the clouds filled the sky and rains, again.
