Hi Bill,
Seeing conditions here in Colorado are, most of the time, pretty so-so. But on occasion we do get some decent atmospheric stability that, when combined with our dark and usually transparent skies, allows higher magnifications. Even so, seeing can vary quite a bit from one night to the next.
I found that having a variety of eyepiece focal lengths allows picking one that yields the maximum magnification seeing conditions will support. That meant biting the bullet and getting several eyepieces in short focal lengths. My short FL collection includes 3.5mm, 7mm, 9mm and 11mm Nagler T6 eyepieces, a Takahashi 5mm LE, and 14mm Radian (OK, this last one isn't really short...). No, I don't own stock in Tele Vue
Seriously, this eyepiece selection allows choosing the optimum FL for given seeing conditions (my main scope is a Tak TOA-130). Sometimes the 11mm is the shortest FL that can be used, sometimes a 9mm works fine but 7mm is too much, and other times the 5mm is best. On those rare occasions of really good seeing, the 3.5mm eyepiece can be used. The latter works out to about 286x, or about 57x per inch of aperture in the Tak.
If you get a chance, go to a star party and try some of the shorter FL eyepieces in your scope. You may find that you want both a 7mm and 5mm eyepiece. Alternatively, you could try a Nagler zoom (I think they're available in 2-4mm and 3-6mm versions), which would let you adjust FL and magnification to suit conditions.
Ron
