Keep the finder-scope covered if not equipped with a solar filter. Direct sunlight may warm the tube assembly enough to cause internal heat currents that can degrade image quality. Cover the tube assembly with a light colored cloth. If possible, do not view over pavement or buildings. Viewing over grass will help avoid surface heat currents.
Point telescope away from sun before removing solar filter.
As with any optic, clean coated surface only if absolutely necessary. If this is a problem, simply tilt the filter slightly. Do not place your filter up against a smaller telescope. The end of the tube will damage the coating or substrate. When looking through the focusing tube without an eyepiece, there may appear to be small defects in the coating which are not seen when observing through the eyepiece.