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lets say i found this plano convex lens (pic) and want to make a telescope.
diameter is 149mm and focal lenght is about 26mm
I was thinking about getting a small plano concave lens as an eyepiece.
what are your thoughts?
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>>1154174
fuck around with the thin lens equation and see if you can make it work
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>>1154174
oops, a typo
i meant the focal lenght is 265mm
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>>1154174
Could work. But the quality might be pretty low. That lens isn't coated optics and is of questionable quality. Besides, I can't tell if the marks in your pic are defects on the lens or dirt on the table top which is now scratching the lens.
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>>1154267
Those are scratches, you can tell because there are many more near the top of the convex side and they are mostly lines.
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>>1154267
Why would the quality be low?
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>>1154174
it's a great idea
make a galilean
go to a paper mill or something and ask for a spent tube (mounting)
get a prism and an eyepiece
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>>1154318
It looks like there are bubbles in the lens?
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>>1154174
>lets say i found this plano convex lens
give it back Jamal
Thread posts: 9
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Thread images: 1