Hi , Ronnie , The earlier posts on this subject cover it well . I've been working on a tagline which I think I haven't yet had occasion to use : Ever wonder why experts use lower powers ? At a higher magnification , you will always see less of a dimmer , fuzzier , shakier image . Of course , that assumes all other factors are equivalent . The IS system or the frame change the equation . For brighter objects , I like to use a pair of inexpensive 7x35's with a 10 degree field of view . For fainter objects , larger , heavier , smaller FOV , more references to star charts , etc. A software-driven telescope would probably be even better . If you have any doubt about being able to bring the image focal plane into your eyes , be sure to look through them before committing to a purchase . There's a huge difference between eyeglasses on and eyeglasses off . Decide first which you think is better for you . If you have enough money , you can buy corrected oculars . Find a star party in your area and attend . You'll likely pickup a great deal of useful information . Also , be sure that the plethora of choices doesn't paralyze you . Many people end up with several pairs . Be sure to start with one . There's an overwhelming probability you'll like it . Since I began taking 50000 IU of Vitamin A daily ( 30 ? ) years ago , my binoculars are much more useful at night . I expected better sensitivity at night , but the much more rapid dark-adaptation came as a very pleasant surprise . According to the Merck Manual , http://www.merck.com/mmpe/sec01/ch004/ch004h.html Vitamin A toxicity sets in somewhere above 100000 IU daily , so don't overdo it . Some people use the non-toxic beta carotene instead of Vitamin A, but you'll have to take far more . My scan of the peer-reviewed literature failed to identify a particular agreed-upon ratio . There've been many recent papers . Maybe something like twice or 20 times as much . A year ago I started taking about 80 mg daily of bilberry , a food , ( European blueberry ) . Within 4 days I found my visual field is brighter and my eyes can focus better when I'm not wearing glasses or using binoculars . There is much more to say about nutritional issues , but probably not here . Cheers , Walter Nissen wnissen@tfn.net -81.8637, 41.3735, 256m elevation --- Of course, pacifism is better. But better can also be dead. ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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