Derby and District Astronomical Society


Comet 17/P Holmes

[Back to Gallery]

This amazing image of Comet Holmes was captured by Chris Newsome on the 15th November 2007. The coma was bigger than the Sun when this picture was taken! Chris used a Celestron C8-NGT with Moonlite CR-1 on an AS-GT mount. A Canon 300D with MPCC and CLS filter attached. A Meade DSI/Skywatcher was used as a guidescope. Exposure details are: 10x240sec at 200ASA and 5x480sec at 200ASA, combined in MaximDL and processed in CS2.



Here is another version of the above image by Chris Newsome, reprocessed to bring out the tail of the comet.



Tony Razzell took this image of Comet Holmes on the 14th November 2007. The picture is comprised of 20 stacked 30 second exposures, dark frame corrected but not flat field corrected. No attempt was made to correct the 'contoured' appearance, only the brightness and contrast were adjusted.



This image of Comet 17/P Holmes was taken by Chris Newsome on the 31st October 2007. Chris used a Canon EOS300D with a 200mm lens at f/5.6. The following exposures all of 30 seconds each were taken: 12x200ASA, 19x1600ASA, 13x800ASA. The camera was piggybacked on a Skywatcher 102T on a Celestron ASGT mount. There was no guiding involved, Chris just let the drive do the work (he had managed to get a good polar alignment when he set the equipment up). Each set of different ASA setting images were combined in MaximDL and then the three resulting master frames were aligned. In CS2, the master frames were layered and opaqued after applying GradientXTerminator, levels and curves. The image was then flattened and a slight unsharp mask applied.



Malcolm Neal took the following image of Comet 17/P Holmes on the 30th November 2007. It is a wide angle view showing the comet against the stars of Perseus with the 'W' of Cassiopeia at the top of the frame. Malcolm used a Canon 400D camera mounted on a tripod on his front porch to be in the shadows as he has a street light just to the left of the house front! He used a 28mm lens with a 10 second exposure at f/5.6 and 1600ASA.



This close up view of Comet 17/P Holmes (visible on the left side of the frame) was taken by Malcolm Neal on the 30th November 2007. Malcolm used a Canon 400D camera mounted on a tripod with a 120mm focal length lens. It is a stacked image of 3 shots of 10 seconds exposure each.



Adrian Brown captured this wide area view showing Comet 17/P Holmes against the stars of Perseus on the evening of the 28th October 2007. He used a tripod mounted Canon Powershot S30 (ISO 400, F/2.8, 15 seconds exposure) to take the image. Adrian noted that the comet was quite easy to see with the naked eye in Perseus and showed a bright disk through binoculars or a finderscope.



This image of Comet 17/P Holmes was taken by Adrian Brown on the 28th October 2007 and processed by Chris Newsome. Adrian used an ED80 on a CGE mount and an ATIK 16HS camera guided on the comet with an 80T/ATIK2HS. He took 40 frames at 30 seconds. Chris then processed the franmes by combining in MaximDL and applying a DDP to the stacked image. In CS2, a second layer was created on the image and this layer had the midpoint level removed, the exposure reduced and then the top layer opaqued with the lower layer by 50%. The top layer then had an unsharp mask applied to bring out the nucleus and then the two layers were flattened. The nucleus of the comet is clearly visible at the centre of the coma and a cloud of dust/ice/debris from the 'explosion' can be seen offcentre within the overall coma. The visual magnitude was similar to that of nearby Mirphak (see image above).



[Top]