The sparse star cluster IC 4665 in Ophiuchus above the yellow star Cebalrai or Beta Ophiuchi. This is a big cluster best suited to observing with binoculars. This is a stack of 4 x 5-minute exposures with the Canon Ra at ISO 800 on the SharpStar 61EDPH II refractor, on the Star Adventurer GTI mount, autoguided with the ZWO ASIAir. Taken from home September 25, 2022.
Large and loose open cluster in Ophiuchus, IC 4665, in a wide-field image simulating the field of binoculars. Taken July 24, 2012, from home with the Canon 5D MkII at ISO 800 and Canon L-series 200mm lens at f/3.5 for a stack of 5 x 3 minute exposures.
IC 4665, the large and sparse open star cluster in Ophiuchus above the star Beta Ophuichi, aka Cebalrai. This cluster stands out well when scanning with binoculars, but is too large and sparse to be a good target for most telescopes. The telesphoto lens used here provides a field of view similar to binoculars. This is a stack of 6 x 2-minute exposures with the 200mm lens at f/2.8 and Canon 6D MkII at ISO 800.
