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If we have an array of telescopes attached one after another, would the resultant magnification be multiplied?Also would such a contraption be feasible to make telescopes with amazing magnification?

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It seems appropriate to mention that telescopes can work together, see e.g. and – Qmechanic Jul 8 '11 at 7:46

If you head down to your local telescope shop and check out their inventory, you might see two telecopes. One is a refractive telescope with a 2 inch aperture, and it has its magnification listed as 1 million. Another is a reflective telescope with a 6 inch aperture and a magnification of 200. Which will allow you to see planets better?

The second one.

Telescopes do two things: collect light and spread it out (magnify it). How much light they collect is limited by the size of the aperture. The magnification is determined by the optics. Note that since magnification spreads light out, it makes the light dimmer. The reason things usually don't look dim in a telescope is because the light has been concentrated from an aperture that's several times larger than the pupil of a human eye.

Note that because of diffraction effects, the amount of detail you can resolve is also limited by the size of the aperture (sometimes; other things can obscure detail more than this, but this is a big one).

To answer your question, you would indeed magnify the images more and more with each telescope, but the reason telescopes are useful is not the magnification so much as the light collection, and that was accomplished by the first telescope. You would be better off spreading the telescopes out to get the full light collection power of all of their apertures, using cameras instead of eyes, and combining the pictures in a computer. This is what some actual observatories do.

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One of the first things I learnt studying astonomy is that magnification of your optics is not as important as resolution of it.

The telescope allows you to see tiny details of celectial objects for three reasons:

  1. It magnifies stuff.

  2. It gives picture with higher resolution.

  3. It redirects more light into your eye -- so you can see faint objects.

Magnification only will not do the job. Think of a dark computer raster picture. Magnification will give you almost no extra details (for example).

And stacking telescopes doesn't help with #2 and #3. I think that it would actually have negative effect.

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Thanks this explains a lot. – eminemence Jul 11 '11 at 4:53

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