The trio of large open clusters ideal for binoculars grouped in Ophiuchus and Serpens — with IC 4756 at left in Serpens, NGC 6633 in Ophiuchus to the right of IC 4756, and IC 4665 at right of frame above the bright star Beta Ophiuchi, or Cebalrai, in Ophiuchus. The pair of NGC 6633 and IC 4756 are also known as the S-O Double Cluster, for their home in Serpens and Ophiuchus. They are an obvious sight when scanning the west side of the summer Milky Way. Below Cebalrai is the large asterism known as Taurus Poniatowski or the “Little Bull,” a group that resembles the Hyades in Taurus. The group was named for the King of Poland, Stanislaus Poniatowski in 1777 by Marcin Poczobutt. The constellation pattern was never accepted but the asterism, now in Ophiuchus, is a fine one for binoculars. This is a stack of 9 x 2-minute exposures at f/2.8 with the 85mm Rokinon lens and Canon 6D MkII at ISO 800, plus a single exposure with the Kenko Softon filter blended in to add the star glows.
The region of the Southern Cross, Crux, at left and around the Carina Nebula, at right. To the left of the Southern Cross is the dark Coal Sack. Open star clusters around the Carina Nebula are NGC 3532 (at upper left of nebula), IC 2602, the Southern Pleiades (below the nebula), and NGC 3114 (right of nebula). Taken on a hazy night, so the glows around stars are natural and not introduced from a filter. This is a stack of 5 x 6 minute exposures at f/2.8 with the Sigma 50mm lens and Canon 60Da at ISO 800, on the iOptron SkyTracker. Taken from Coonabarbran, NSW, Australia, March 22, 2014.
The deep south Milky Way from Alpha and Beta Centauri (at left) to the False Cross in Vela and Carina (at right). At centre is the Carina Nebula and the Southern Cross, Crux, with the dark Coal Sack. Omega Centauri is the bright “star” at upper left. The large naked eye star cluster at lower right below the False Cross is NGC 2516. This is a stack of 5 x 4 minute exposures at f/2.8 with the 35mm Canon L-series lens and filter-modified Canon 5D MkII at ISO 1000, with an additional similar exposure layered in taken through the Kenko Softon A filter to provide the star glows. Tracked on the iOptron Sky Tracker. Taken from the Warrumbungles Motel grounds at the 2016 Oz Sky Star Party, April 5.
