THE THREE "C"s OF OBSERVING

• THE THREE "C"s OF OBSERVING: MAXIMIZING YOUR OBSERVING SUCCESS

THE THREE "C"s OF OBSERVING WITH A TELESCOPE
To get the most out of a telescope, try maximizing the three "C"s of observing:
1) Collimation.  The alignment of the optics in the scope.  Very slight misalignments can ruin the quality of both star and planet images.  Learn how to collimate and check frequently to make sure you are maintaining good collimation
2) Cooling.  Most people don't know that when the optics are at a temperature higher than the surroundings (the "ambient" temperature) they don't produce images that are as good as when the optics have cooled to the ambient temperature.  The reason is that glass used in optics holds its heat and releases it slowly into the surrounding air.  The warmer air layer just on top of the glass causes a distortion in the images when light passes through it--twice in a reflector!  Any reflector larger than 6" should have active cooling from a fan or fans blowing on the mirror to help eliminate the residual heat in the optics.  Refractors, primarily because they are smaller, cool down much more quickly.
3) Conditions.  The presence or lack of turbulence in the night sky (called "Seeing"), and the darkness of the sky (absence of light pollution) and the transparency (clarity) of the air all combine to produce better images and allow us to see fainter objects and sharper, crisper, images.  We don't have much control over these, but you can maximize your potential:
• to improve seeing, try observing from the center of valleys or from the windward side of mountain slopes.  If the air above you is stagnant or moving in a "laminar" (layered) fashion, you will see better images and less turbulence.
• to improve darkness, try transporting your scope occasionally to sites far away from cities, where the skies are darker.  Even here in LA, we can drive away from the lights.
• to improve transparency, observe from higher altitudes (where there is less water vapor and dust in the air) or areas far away from cities (to reduce smog and local air particulates).
Remember the three "C"s, and try to maximize each one, and your scope will perform to its potential.  That doesn't mean you can't observe from the city--in each city there are great places to set up to observe the Moon and planets and maybe double stars.  In a lot of cities, the air overhead is very steady, and that's exactly what you need for that type of observing.

Best of luck, and clear skies!