A mosaic of the region around the Small Sagittarius Starcloud and Dark Horse dark nebula complex. The field takes in the Milky Way from the Lagoon Nebula at bottom to the Eagle Nebula at top left. In between from top to bottom are the Swan Nebula (M17), and the Small Sagittarius Starcloud (M24). Flanking the bright M24 starcloud are the large open clusters M23 (right) and M25 (left). At bottom left is the M22 globular star cluster. The prominent dark nebula at right is the large Pipe Nebula (B78) with the small Snake Nebula (B72) above it. The whole complex is visible to the naked eye as the Dark Horse. This is a mosaic of 4 panels, each a stack of 5 x 3 minute exposures with the 135mm lens at f/2.8, and with the filter-modified Canon 5D Mark II at ISO 1600 tracking the sky on the iOptron SkyTracker, with no guidind. Images were stacked and stitched in Photoshop CC. Taken from the Four Bar Cottages near Portal Arizona, May 4/5, 2014.
Sword of Orion taken from Timor Cottage, Coonabarabran, NSW, Australia, December 13, 2010. This is a stack of 5 x 7 minute exposures at ISO 800 with Canon 5D MkII camera on 77mm Borg astrographic lens at f/4.2 (~300mm focal length). Contain M42 and M43 the Orion Nebula; the Horsehead Nebula; and NGC 2024 the Flame Nebula.
A portrait of three comets each passing the Pleiades and in a similar location relative to the star cluster, but taken over a span of 14 years. And I shot the first (Machholz) and latest (Wirtanen) comets with the same lens, a 200mm telephoto, from my backyard in Alberta, while the middle image of Lovejoy I shot with a 135mm telephoto for a wider view than the others, and it was shot from New Mexico. On the left is Comet Machholz (C/2004 Q2) discovered in 2004 by amateur astronomer Don Machholz, at centre is Comet Lovejoy (C/2014 Q2) disovered in 2014 by amateur astronomer Terry Lovejoy from Australia, while on the right is Comet 46P/Wirtanen, discovered in 1948 by professional astronomer Carl Wirtanen. All the comets became bright enough to be visible to the unaided eye, though only just. But all were fine photogenic targets, with Lovejoy sporting the long blue ion tail. I shot Comet Machholz with a Canon Rebel 300D cropped-frame camera, Comet Lovejoy with a full-frame Canon 5D Mark II, and Comet Wirtanen with a Canon 6D MkII full-frame camera. So with the different sensor sizes and the use of two different lenses the images scale is not the same over the three images.
