The following information is from the;
published by Joe Roberts & Peter Chapin
Simulated Telescope Planet Images
The purpose of this page is to provide you with some idea the view to expect from various size telescopes at various magnifications. For this example we will consider a view of the planet Saturn. First we will show approximately how Saturn might look through three different telescopes operating at magnifications within their useful capability. Then we will show what to expect as a small telescope is pushed beyond its useful magnification range.
Important: It must be remembered that the images on this page are simulated (the image of Saturn is one I took through my Celestron CG-11 scope however). No monitor can cover the brightness range that the telescope (or the human eye for that matter) can see. Thus, do not expect telescope images to appear exactly as those depicted here. The proper calibration and maintenance of the technologies we use will allow us to see an image of the planet’s likeness but not an exact account. The main purpose of this page is to provide an approximate comparison of the relative performance of various sized telescopes. Actual views through a real telescope depend on many factors; telescope (and eyepiece) quality and seeing conditions are the two most important determining factors. The simulated images below assume a decent quality eyepiece is being used, one with an apparent field of view of about 50 degrees (in other words, similar to a typical Plossl eyepiece). If nothing else, this page will help to show why any astronomer will tell you that “department store” telescopes (such as Tasco, Jason, Bushnell, etc) cannot show quality images at the preposterous magnification capability claimed by these instruments!
If the calibration bar below does not show 16 distinct shades of gray, the images on this page will not display in an ideal manner!
Saturn through an 11″ scope at 400x (simulated)
Saturn through a 5″ scope at 200x (simulated)
Saturn through a 3″ scope at 100x (simulated)
Saturn through 5″ scope at 400x (simulated)
Saturn through a 3″ scope at 400x (simulated)
From the above we draw the following conclusions…
- A larger telescope will show brighter images than those in smaller scopes.
- For an image in a smaller telescope to be as bright as that in a larger telescope, the magnification must be less (example: a 3″ scope at 100x will have the same image brightness (on planets or the Moon) as a 6″ scope at 200x).
- Small scopes pushed to absurd magnification will yield views that are not useful.
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