The CCD cameras at the observatory are very light sensitive but have a smaller number of “megapixels” as compared to the digital camera that you may be using at home. The CCD chip in many digital cameras today might also be physically larger in area which corresponds to a wider view of the sky. I have been experimenting with my DSLR (Canon EOS450D) to take wide field deep time exposures. Operating at ASA400 to keep the noise low, exposure times can get long! In the attached image of the North America Nebula (NGC7000), a total of 90 minutes of light time was collected (with 18 five minute exposures). NGC7000 is a very challenging faint gas nebulousy in a rich star field of the Milky Way. The key to these long exposures is acurate tracking of the sky – something the Harken Observatory telescope does very well. I also tried imaging M31 and M27. M31 is the Andromeda galaxy and is very large in sky area. M27 is the “Dumbell Nebula” which is a planetary nebula (an exploded star shell). These images are at the same magification so you have a feel of the actual size up in the sky.
Note: I have re-posted these images with the correct color balance.
Enjoy!
North America Nebula
Andromeda Galaxy
Dumbell Nebula
