Some rejuvenated data to allow for better
rating estimates of night sky transparency with the naked eye: a selected
Polaris area with visual magnitudes from Tycho/Hipparchos data (charts
by Guide7).
No need to bear Picasso's name to use
a pencil in order to draw the deep sky ! You can learn the bases and find
tricks to record cheaply your deep sky observations...
For the same diameter, which instrument
to choose ? A Schmidt-Cassegrain, a refractor, a classical Newton or why
not a Maksutov ? In this article, you will find a way to compare performances
of all instruments destined to deep sky observing.
You never obtain sharp images and don't
know how to check your instrument collimation. Here are the detailed explanation
of optical checkings and adjustments (collimation) that you can apply to
your Newtonian, whatever its aperture.
