When beginners, bubbling with enthusiasm, take their first look through a telescope, they occasionally express disappointment in what they see — or, more likely, what they don’t see. Having been entranced by the beautiful images of galaxies and nebulas displayed in books and magazines such as SkyNews, novice observers may find the reality of the telescopic view, where the object under scrutiny is sometimes faint and often colourless, something of a letdown.
However, colour photos and the view through a telescope are two entirely different things. The beginner learns early on that the impressive colour photos are long time exposures of many minutes (or even hours!) that accumulate faint details well beyond the limits of the human eye at the telescope eyepiece, regardless of the size of the telescope. Moreover, a second and more subtle reality is that it takes observing experience to know how to see and how to exploit the telescope to the fullest. But how does one go about developing this ability? The best way I know is to make detailed notes of your observations and, in particular, to sketch what you see at the eyepiece.
I first became aware of the value of recording my observations when I happened upon an Astronomy Day exhibit at a Montreal shopping mall 25 years ago. At the time, my interest in astronomy had just been rekindled, and I was the proud owner of a 6-inch telescope. The colour photos and posters on display caught my eye, but what really piqued my interest that day was a carefully kept journal of observations. I distinctly remember that it was open to an observation of Messier 3 made with a 4-inch Schmidt-Cassegrain telescope. Accompanying the notes was a sketch of the cluster showing a glowing ball of light surrounded by what seemed like dozens of stars. I had recently ob- served M3 with my 6-inch scope but had seen only a hazy, ill-defined glow. How could a 4-inch telescope show more than my 6-inch?
I spoke with the owner of the telescope, who said that taking the time to sketch what he observed encouraged him to be patient and really examine the view through the eyepiece. The longer and more intently he looked, the more he saw. “I’m not much of an artist,” he said. “My drawings only hint at how beautiful these objects actually are.” I resolved then and there to start recording what I saw in my telescope, and a quarter of a century later, I’m still at it.
The beauty of sketching and recording what you see is that with practice, it is easy to do. Years ago, I created a preprinted form that helps me organize my observations. As well as recording the object, location, date and time of the observation, telescope used and magnification, I also write a 50- or 60-word description of the object. A circle 65 millimetres in diameter on the form represents the eyepiece field, in which I sketch the object and the surrounding field. The sketch and written comments reinforce each other, making for a complete observation.
The materials I employ are very simple. I use a lead pencil to display nebulosity, my favourite being the Berol “primary printer” pencil used by young children when they are first learning to print. The thick-barreled pencil is comfortable to grip, and the lead is easy to apply to paper and to manipulate. I use a black-ink, metal-point pen to place the stars. The relative brightness of each star is easy to reproduce: A short “poke” at the paper represents a faint star, while a slightly longer application allows the ink to blot the paper, creating a brighter star.
Because most galaxies, nebulas and star clusters are subtle objects, a light touch is essential to produce a realistic image. A few strokes with the side of the pencil in the rough shape of the object is all that is required. I use my index finger in a back-and-forth or circular motion to gently smudge the lead into the desired shape and intensity. To represent the brighter core of a globular cluster, I apply more lead, as necessary. I carefully plot the positions of nearby stars and asterisms, which adds to the authenticity of the image. Shown here are some examples of objects both bright and faint that are well placed for observation on summer nights. (Originally made on white paper, the sketches are reproduced here in negative to more closely resemble the telescopic field of view.)
Twenty-five years on, I have accumulated dozens of “smudge books” documenting over 3,000 deep-sky objects I have observed using telescopes ranging from 6 to 25 inches in aperture. These are a record of my personal journey through the cosmos and have helped me become a better observer. If you haven’t done so already, why not start your own “star journal” on the next clear night? It’s well worth the effort!
Mark Bratton has never met a deep-sky object he didn’t love. Whenever he takes his telescope out, he sees something new. He enjoys sixth-magnitude skies from Limerick, Saskatchewan.