So with the ongoing trend of overcast skies, I thought I would take this time to introduce the tools that allow me to view and capture the skies above.
First of all, and most importantly is the telescope tube itself, a Sky-Watcher 150mm/750mm Newtonian Reflector designed with astrophotography in mind. Its shortened tube, fast focal ratio (f5) and 2″ focuser allow for excellent prime focus astrophotography. Though the tube itself was excellent to begin with, I’ve decided to line its interior surface with an optical flocking material (which absorbs reflected light, minimizing stray light and increasing contrast).
The mount is a Sky-Watcher EQ3 equipped with the SynScan hardware. This allows me to point the telescope to any given object based on name, location, or catalogue number with the simple press of a button (following a polar alignment of course).
Due to increased weight of the rig, the standard counterweight system had to be modified. Adding extra weights would have been one option, but I chose the MacGyver route and fabricated an extended bar. A 3′ length of M18 threaded rod, thin wall EMT conduit, and a couple of locking M18 nuts did the trick.
Having a motorized mount and decent sized telescope would be more than enough for visual observation and short-exposure; however, long-exposure astrophotography requires precise and smooth tracking to yield successful results. The problem in taking photos of faint object is the I’ve accomplished this through the use of an autoguiding system comprised of the SynGuider autoguider, 80mm Guide Scope, and a customized mounting bracket. Autoguiding is a means of precisely tracking a target using a nearby star as reference. As the mount tracks, the autoguider constantly keeps track of the guide star. Should that star drift from its original point the autoguider with send a correction to the telescope mount which in turn compensates for the drift. The end result is an image with beautiful round stars rather than a streaky mess of white lines.
As for the device I use to actually capture images, I use a modified Canon 40D. The modification involved opening the camera and removing two glass filters which block IR, UV, and other unwanted wavelengths that would normally ruin a normal photo. But those wavelengths are exactly what is needed to view many nebulae. In essence the modification opens the camera’s original sensor to the full spectrum accessible by that particular chip (More spectrum = More Colours = More detail visible in photographs). The proper way to modify the camera would have been to replace the filters with a clear optically perfect glass substrate; however those are costly so I will live with the disadvantage of having to clean my CMOS sensor manually.
Then there’s the assorted accessories
And my power supply when there’s no power to be found
It may seem like a rather large amount of equipment, but when used together properly they simply mesh and operate as a single tool allowing me to complete my work and survey the cosmos. There’s so much to see, and I would encourage you to start looking up a little more often, you might just catch a glimpse of something amazing.