Backyard astronomy in the suburbs

Observing large open clusters

In the last few months I have been observing some large open clusters with binoculars. On Saturday november 20 last year I observed and sketched Melotte 20 in Perseus, also known als the Alpha Persei Moving Cluster. This huge starcluster has a diameter of almost 5 degrees. The observation was don with a 10x70 Fujinon binocular mounted on a mirror mount. The careful observation and the sketch took me about 1.5 hours. Later I scanned the pencil sketch into photoshop and made a more "realistic" version. Due to the mirror I use for observing, south is up and east is to the left.

Melotte 111: the Coma Berenice Star Cluster

A few weeks ago I observed the Melotte 111 in Coma Berenice. This huge star cluster with a diameter of at least 5 degrees is actually too big for most of my instruments. I used the skywindow and my 8x42 binoculars with an 8 degree field of view for the sketch. It is a truly great object for binoculars.

South is up, East is to the left.


Updated sketch of Stephenson 1

At the moment I am trying out new methods for digital processing of my sketches. The sketch below, of Stephenson 1, an open cluster in Lyra, is based on an observation I did a few years ago. I do all my sketches in pencil and on white paper, scan them into Photoshop, and proces them. The method I use is based on several different manuals from fellow astronomers who sketch at the eyepiece, but mostly on Peter Vercauteren's manual ( for Peter's website) and Jeremy Perez's manual ( ). The beautiful sketches of these guys are an inspiration for me!

Sketch of Stephenson 1 in Lyrae, from 30th august 2010. Instrument Orion Optics UK 300mm,
Nagler 22mm, magnification 73x, true fov about 1 degree, south is up, west is to the left.


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