23 Dec
2008
23 Dec
'08
9:24 a.m.
A good way to start astro-imaging is to to "piggyback" photography. Instead of shooting through the telescope at long focal lengths, you use the camera with a telephoto lens, attached to the main telescope. You guide using the main scope, with a cross-hair eyepiece (or an autoguider if the mount will accomodate one). Many objects are large enough that a telephoto lens will capture it perfectly. M31 and M33, for instance, subtend an angle greater than the full moon. And there are many star clouds and extended nebula that are excellent subjects for a telephoto- not to mention the occassional comet. Skills honed in this way are easily transferred to imaging with longer focal lengths once the basics are mastered.