perfect seeing and plenty of sunshine and no nearby obstructions/turbulence generators or forest fogs - what magnification do you think a 70mm f/14 achromatic refractor can acheive without a loss of contrast or image blurring?
2007-09-17 04:46:27 · 3 answers · asked by OK 1 in Science & Mathematics ➔ Astronomy & Space
Generally, the rule is 60X per inch of aperture. This is all dependent on seeing conditions, light pollution factors, the quality of your optics, etc.
These number are generally a basic guideline; some times the magnification factors are much lower, due to seeing conditions and light pollution. Sometimes the numbers can be higher; I've been able to reach (under the BEST possible conditions), magnifications of just over 700X in my 10" Schmidt-Cassegrain.
Saturn was gorgeous that night, filling almost the entire field of view!!!
2007-09-17 05:12:41 · answer #1 · answered by Bobby 6 · 1⤊ 0⤋
Even the lowest magnification has some loss of contrast and clarity. There is no cutoff level below which there is perfect contrast and clarity. The image just deteriorates gradually as you increase magnification, then it is a judgment call when the image quality is no longer acceptable. The usual rule of thumb in 50 power per inch, which would be 2 power per millimeter, That would be 140 power for a 70mm telescope.
2007-09-17 13:21:27 · answer #2 · answered by campbelp2002 7 · 1⤊ 0⤋
About 35X with a 2mm eyepiece
2007-09-17 11:59:13 · answer #3 · answered by Anonymous · 1⤊ 0⤋