The Ha filter cuts out all the light from M101 except for the Ha light from the bright star forming regions in the spiral arms.
View full sized image of M101 Pinwheel Galaxy
cCaptured in maxim.
This image was autoguided using my homemade off axis guider with Lodestar.
Imaged with my homemade telescope mount
Exposure Details :
Coma Corrector Astrodon 3nm Ha 10x900s on 200 @ F5 f.l. 1000 with Artemis 285 camera
Equipment:
Curdridge Observatory, Southampton,UK