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Arc minute

Reinforcing OTA newt

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Since it is saturday, I can ask silly questions, eh?

There are posts describing how fellow astronomers have made improvements to their steel tubed newts. However, it seems that these topics are quite old and the accompanied photos are no longer available. From the descriptions it can be determined that all have approached this by adding the strengthening plate inside the tube. (And now the silly part) Why everyone has been doing it to the inside of the tube? It would seem that reinforcing with a plate to the outside of the tube should yield the same effects with lot less effort; no extra flocking, no need to disassemble the whole ota etc.. 

Of course adding the additional plate outside the tube will affect the amount backfocus available but the effect would be marginal. 

There is probably something I Am missing here so please enlighten me, so I can avoid doing this twice ;).


Thanks, and great saturday for you all!

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I'm not sure here,  but it is it because adding them to the outside would make it more complicated with any tube rings fitted to the scope tube, plus it'll make it cosmetically uglier on the outside rather than the inside where these supports are not seen mostly? 

Edited by Knighty2112

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Thanks Gus! Yes the tube rings is a good one, have to test If it has any effect If the plate covers the whole circumference. I would think that the ring would still fit, but this has to be tested. 

Cosmetics is not a problem, atleast for me, since I use the scope in the dark and threre's no one looking anyways ;)

One thing I have Been pondering is that If the plate is placed inside the tube and you don't make it to cover the whole circumference of The OTA (is not a complete tube), how it might make various reflections/diffractions. Does anyone have experience on this?


Edited by Arc minute

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