Wednesday 10 September 2014

M13 The great globular cluster in Hercules

This globular star cluster is visible to the naked eye shining at magnitude 5.8. It lies in the constellation of Hercules at a distance of about 22,000 light years .The sky conditions were hazy with  a bright full moon. I captured a composition of sub frames, five minutes and sixty seconds . I combined them together to avoid core saturation revealing inner and outer detail through out the entire image . I also took matching dark frames and flat field frames to avoid vignetting . I was using a ten inch f/4.8 reflector , PHD auto guiding and an Atik 383L CCD camera. The total exposure times were twenty minutes for each colour filter.


Sunday 7 September 2014

NGC7317. Stephans Quintet

This group of galaxies lies in the constellation of Pegasus shining at about magnitude 14.5. I took this image using a ten inch F4.8 reflector , PHD. auto guiding and an Atik mono 383L CCD camera. I captured five minute sub frames with matching dark frames and combined them with flat field frames to reduce the effect of vignetting in the final image . The total exposure times were 50 minutes using a blue filter, 25 minutes using a red filter and 15 minutes using a green filter.


NGC 7331 was included in this composite image: