A 30$ svbony SV501 telescope. slight modification.

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realflow100 United States of America
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A 30$ svbony SV501 telescope. slight modification.

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Post by realflow100 »


I just purchased a new very cheap 30$ telescope (just the scope. no tripod) 70mm F6 diameter and focal ratio
i was wondering what was going on because at high magnifications the whole image had shifted aberrations red to the right. and blue chromatic aberrations to the left of objects.
I discovered the cell holder has too much tolerance in it. making the lens elements rattle all around in there.

so I put 3 strips of packaging tape around the elements to take up the space. now its pretty much perfect. uniform image. no aberrations on any side.
looks hugely better and clearer now.
i need to do star test to see how much under/over correction it has. but i'm thinking it has slight overcorrection.
it has a thin black spacer ring to space the elements out.
The inner surfaces are all matte-black and it has decent baffling also (Not too bad for cheap scope)
only thing thats lacking is non-blacked edges of the elements (Not going to expect that for 30$ anyways)

I dont know why they either made the lens elements very slightly undersized. or the lens holder slightly oversized. instead of making it a more snug fit. it would look

breaking the threads loose to get the cap holding the elements in was quite difficult seemed to be glued together slightly. but i was luckily able to break it free with a rubber cord wrapped around it for extra grip (twisted and giving me more torque to rotate it by hand)

At 70x magnification the image seems decently sharp. a little soft at 140x. but i'm not sure if its due to the optics or atmospheric seeing (its day time right now. so everything is warping and distorting and waving like theres a layer of water over everything like a mirrage you see in a desert or hot road surface.
Note I'm using my own 90 degree mirror diagonal instead of the included prism diagonal.
The included prism diagonal is ok at 40x magnification or lower (image looks ok there)
Svbony SV503 70mm ED F6 420mm FL refractor telescope (New)
Canon EOS 100D/SL1
Tamron 18-200mm F3.5-F6.3 II VC lens
canon 50mm STM F1.8
svbony 8-24mm zoom eyepiece
svbony goldline 66 degree 9mm and 6mm + 40mm plossl + 2x barlow.
svbony UHC 1.25 filter + astromania 1.25" O-3 filter + also an svbony H-B filter.
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