The lens pair balances a strongly convex crown (low index and low dispersion) with a weakly concave flint (high index and high dispersion). Glass has two key properties in play here - its index of refraction (how much it bends light) and its dispersion (how much that bending changes over color). The lens pairs that James mentioned (crown and flint) are known as a doublet. I generally agree with the answer above, but have a couple more insights which might help you if you decide to proceed with trying to make your own scope. Apart from that, I would also like to use the big aperture of lens 1, for viewing DSOs, But, it has a very short focal length(just 200mm), and therefore, I am finding it hard to get any eyepiece lens which can "completely accommodate the exit pupil of my scope"(as said on skyandtelescope )Īny way to get such a lens, or make an eyepiece barrell sort of, using a combination of lenses mentioned above or buying. I have accepted 's answer and am on my way to making it. Is there any way I could use the lens 1 in a telescope which I could use to view the planets? I live in a suburb and it is not very lighted up. I would like to know which lenses should I use, or buy and the way to use it. I am ready to make separate telescopes also, if suggested. I would like to know the way to make the telescope, which I would like to use to observe planets and DSOs if possible. Upon seeing the Moon, I could just see it a little bigger than what would be seen with the naked eye. This telescope showed me a bright Mars, Jupiter and Saturn, but as dots. I made a telescope using lens 1(as objective) and lens 3(as eyepiece) which on calculation, gave a magnification of 9x, but according to and the minimum magnification is 14x and that I was 'wasting' the light gathered by the objective lens. I can also buy lenses of range of Power(In Dioptres) from (-14D) - (+14D) of aperture range of 5.5 cm to 7 cm, if suggested. 1 convex lens - focal length 200 cm aperture - 5.5 cm.
1 concave lens - focal length 8.33 cm aperture - 5.5 cm.1 convex lens - focal length 2.2 cm aperture - 2.5 cm.2 convex lenses - focal length 17 cm aperture - 5 cm.1 convex lens - focal length 20 cm aperture - 10 cm.Apart from that, I have the following lenses lying around:. I read up that the aperture was a very important aspect and thus bought a convex lens with 100mm aperture and 200mm focal length, to use it as an objective lens.
I wanted to make a telescope with DIY things lying around in home.
0 kommentar(er)
