My RX80-L Refractor

Wanna make a scope? Or better still, grind a mirror yourself. Or, you have some good tips in making a really useful accessory? This is the place to show what your hands can do...
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harlequin2902
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Post by harlequin2902 »

Yeah ! The mounting rings and tripod adapter finally arrived today and the RX80-L can be mounted properly on a mount at last. The Skywatcher 3.5" tube rings fit perfectly. I hope to be able to test it this Sunday evening.

Here are some more pictures to share :

The RX80-L taking it's place in the living room
Image

The RX80-L on a Manfrotto 410 head
Image

:)
Samuel Ng
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Airconvent
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Post by Airconvent »

mm...Sam...the scope looks pretty decent aesthetically!
maybe if cost is low, you can make a few and sell them!
btw, how much would it have cost to make the scope based on your retail price for the components?
looks like I would have to consult you as to how to convert my surplus shed 50mm freak scope into something more presentable...

rich
The Boldly Go Where No Meade Has Gone Before
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United Federation of the Planets
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harlequin2902
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Joined: Tue Sep 30, 2003 11:04 am
Location: Singapore, Sengkang

Post by harlequin2902 »

mm...Sam...the scope looks pretty decent aesthetically!
maybe if cost is low, you can make a few and sell them!
btw, how much would it have cost to make the scope based on your retail price for the components?
looks like I would have to consult you as to how to convert my surplus shed 50mm freak scope into something more presentable...

rich


The breakdown of the costs for the complete RX80-L OTA based on M.S.R.P (manufacturer suggested retail price) :

Imported :

80mm objective with cell - S$150.00
2" R&P focuser - S$100
Mounting rings & tripod adapter - S$90.00
1.25" prism diagonal - S$45.00
Red dot finderscope - S$50.00

Shipping is an estimated S$120.00 for all the above items. UPS rate.

Locally available :

Those silver coloured rings - S$2 each. Used 6 of them so it's S$12 in all.
A can of Ivory spray paint (Nippon) - S$5
3.5" diameter, 75cm long PVC pipe - S$5

S$577.00 total. Still can't beat the prices of factory mass produced scopes, but the fun of putting your own scope together and the sense of achievement that comes with seeing it work (Saturn at 150x is still Saturn with the rings, a hint of the Cassini Division and banding around the equatorial region) is absolutely priceless.
Samuel Ng
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kayheem
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Location: Sennet Estate

Post by kayheem »

harlequin2902 wrote:
mm...Sam...the scope looks pretty decent aesthetically!
maybe if cost is low, you can make a few and sell them!
btw, how much would it have cost to make the scope based on your retail price for the components?
looks like I would have to consult you as to how to convert my surplus shed 50mm freak scope into something more presentable...

rich


Still can't beat the prices of factory mass produced scopes, but the fun of putting your own scope together and the sense of achievement that comes with seeing it work (Saturn at 150x is still Saturn with the rings, a hint of the Cassini Division and banding around the equatorial region) is absolutely priceless.
Welcome to the world of Amateur Telescope Making (ATM)! :D

An ATM-ed scope will always be unique. You will be using *your* scope and the feeling is great , especially if it performs well. Only problem is getting people to see the 'beauty' of the scope when you are trying to sell it.

Kay Heem
ChaosKnight
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Post by ChaosKnight »

Ya know....if you used 6061 aluminium, the error in the angle of incident light from the objective on the eyepiece is reduced to 0.06 that when PVC is used?
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weixing
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Post by weixing »

Hi,
Ya know....if you used 6061 aluminium, the error in the angle of incident light from the objective on the eyepiece is reduced to 0.06 that when PVC is used?
I just wondering what do you mean??? And also what is that 0.06???

Have a nice day.
Yang Weixing
:mrgreen: "The universe is composed mainly of hydrogen and ignorance." :mrgreen:
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Debash
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Post by Debash »

Weixing, you have hit the nail on its head with a good sense of humour :lol: can't stop laughing after reading your questions!!
Debash
ChaosKnight
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Post by ChaosKnight »

For an optical system to perform optimally, the light along the principal axis from the objective must be normal to the lens of the eyepiece. Any deviation from such a 90 degree angle can be considered an error.

Because telescope tubes flex, such an error is always present. The only way to improve optical performance is to reduce flexing through choice of materials or geometry of the tube.

By replacing a PVC tube with a geometrically identical aluminium tube, this error can be reduced to 0.06 of its former value.

Sorry Debash, but what's so funny?? i don't geddit......
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weixing
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Post by weixing »

Hi,
Hmm... But how do you get that 0.06... I mean how do you know that with an aluminium tube, the error can be reduce to 0.06 of its former value?? Also, what is the unit for the 0.06?? I hope you can give more explanation when you give such numbers...

Have a nice day.
Yang Weixing
:mrgreen: "The universe is composed mainly of hydrogen and ignorance." :mrgreen:
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zong
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Post by zong »

yes, I'm quite curious at how you arrive at 0.06 too. There's no one lens and tube combination in this world that can achieve such perfection in the first place, so on what basis are you giving your comparison? and .06 of its former value, as i understand, is .06 of the error caused by using PVC instead of aluminium tube, which is indeed a great claim! Can you try to explain a little more at how you arrived at that number. Thank you.

Yea I don't understand what's so funny about weixing's question, too... It's afterall perfectly logical to question the illogical, right? :lol:
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