I have read the question How do telescopes work as magnifiers? but it doesn't quite address, as far as I can tell, my question.
I'm trying to wrap my head around why magnification works rather than how it works. Based on my understanding of the functioning of lens-based magnification, the three objects all function, essentially, the same way:
I'm intentionally ignoring reflective mirror-based telescopes for simplicity. Sets of curved lenses refract light, thus collecting more light, to specific focal points creating virtual images where more details can be perceived. Though I'm not deeply versed on the formulas that describe this phenomena, I understand the basics.
What I'm grappling with is that magnification happens at all. Assuming my understanding is correct, this would mean that, standing on a high mountain on a clear night and looking up at the stars with the naked eye, the "information" that's available to our eyes is that same as the information available to an observatory telescope nearby.
I imagine the explanation is simple but I can't "fill in the gap" that makes such a dramatic difference in perceptible (not accessible) information between the naked eye and the sky seen through the telescope. Why does "more light", which is fairly diffuse and coming from an extremely distant origin (another planet, for example), produce so much extra perceptible information?
If someone has answer, that would be amazing but I would be just as happy as being pointed to a good discussion of what's really happening.
Best Answer
The light carries the information just fine. But your eye can only distinguish and interpret this information down to certain resolution due to the size of the rods or photoreceptor cells in your retina.
Basically, if your visual sense is a screen then each pixel on this screen can only depict one colour. Showing an enormous image will thus requires trade-off's when several pieces of information is comes with the same pixel. The pixel can only show one and thus must choose a way to "blend" it together. Enlarging a smaller portion of the full picture, which is what a telescope does, spreads out the information bits our your visual "screen" allowing for the details to be spread out more, thus covering more pixels and thus becoming distinguishable.