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Object Data: NGC 7000, the North America Nebula, is located in the constellation of Cygnus. It is a very large area of emission nebulosity extending some 2.5 degrees to the east of Deneb. It was discovered in the early 1890s during experiments into wide field astrophotography. Several areas of nebulosity can be seen surrounding NGC 7000 including IC 5070, the Pelican Nebula to the west and IC 5068 to the south. The 'Skull Nebula' can also be seen between the North America and the Pelican nebulae.
Date of Exposure: 20/9/98 and 21/9/98
Location: Wiltshire, U.K.
Conditions: 20/9/98: Calm, Transparency=7, Seeing=7. 21/9/98: Moderate Breeze, Transparency=9, Seeing=5.
Telescope: Meade LX200 10" f/10 used as a mount / guidescope for the lens
Off-Axis Guider: None
Autoguider: SBIG ST-4
Camera / Lens: Nikon F2 with Nikon 400mm f/3.5 lens (working at f/4) mounted piggyback on the LX200 which was autoguided by the ST-4
Film: Gas Hypersensitised Kodak Ektapress Mulitspeed PJM-2
Filtration: Lumicon Deep Sky Filter
Exposure: 20/9/98: 2x 40 mins. 21/9/98: 2x40 mins.Enhancement: Four original negatives were stacked in register and digitally combined in Picture Window with image enhancement in Photoshop.
Notes: Transparency on 21/9/98 was exceptionally good for the UK (reminiscent of southern France). Both exposures on 20/9/98 were inadvertently taken at f/3.5 (I forgot to stop the lens to f/4). I thought that these exposures might be unusable through over exposure, however they were fine, and happily all four exposures turned out to be of good quality. Many thanks to Jerry Lodriguss for his excellent technique: Digitally Removing Uneven Field Illumination which was used on all four images prior to stacking.
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