Question for people who know a lot about optics.?

2014-11-10T23:42:45Z

Forgot to add details... give me a minute to type this

2014-11-10T23:47:59Z

My understanding is there is something that limits a telescope larger and larger telescopes from increasing the surface brightness of diffuse objects. More and more light is gathered, but it is spread over a larger area.

I can't remember why, because I read about this maybe 10 years ago and I did like a ton of meth.

2014-11-10T23:49:39Z

Anyway, Thinking about it I'm guessing that even though a 10 and 20 inch telescope can both provide 100x, all things being equal a 20 inch telescope will gather 4 times as much light but spread it over a 4x larger exit pupil by area. Is that right? can anyone explain this in detail, or provide a link that does?

2014-11-10T23:49:53Z

Anyway, Thinking about it I'm guessing that even though a 10 and 20 inch telescope can both provide 100x, all things being equal a 20 inch telescope will gather 4 times as much light but spread it over a 4x larger exit pupil by area. Is that right? can anyone explain this in detail, or provide a link that does?

2014-11-10T23:50:54Z

Oh and I'm clean now.

2017-04-11T00:37:33.809Z