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Making good use of poor scopes


jnb

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I've acquired a number of really dodgy scopes over the years. Some I have split in half so that I can show people how scopes work. Some I have made myself so that I can show people just how bad Galileo's first scopes were.

A friend showed me recently a scope they had which they couldn't get to work; it's a zennox 700 76 - so a basic 3" altaz newtonian but no eyepieces. Now my reaction would be to bin it and get something real but equally the fact that I've played with really bad scopes and got something out of it makes me think I should just give them some of the spare Plossls I've acquired over time and suggest they try it. So what would you suggest? Make best use of bad equipment or cut their losses and get something halfway decent?

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Oh I could use it, as a demo instrument. I'd do what I did to a cheap refractor and cut it clean down the middle to show the workings. It's someone else's scope and they don't have my experience the question is what could they best do with it.

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I have been in this position but with a guitar rather than a telescope.  

Along time ago about 1981 when I was a poor student I bought a guitar from a second hand shop for £50 which was a lot for me.  Once I started working I bought a better guitar but I did still like the cheap one.  

As is the way it sort of deteriorated and became unplayable.  I asked several knowledgeable guitar playing people and they just said it was not worth repairing.  I tried to part exchange it but £80 seemed a bit cheap.  

I found a guy who set up guitars and paid him to setup my "good" guitar.  Well it came back better than when I had bought it.

So I showed him my old guitar.  He said there is no such thing as a bad guitar. So I let him fix it.

My niece has starting out glass blowing and she very kindly made me a bottle neck. She wanted to see what the bottle neck was like so I recorded an abridged version of "In  my time of dying".  I'm no Jimmy Page but it seems like the guitar was made for it. And the bottle neck is a work of art.

https://www.facebook.com/graham.newton.35/videos/vob.1612985902/10205429871978898/?type=2&theater

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But there is such a thing as a poor telescope. If the objective lens or primary mirror is badly figured then it's simply not going to reach sharp focus whatever collimation adjustments are made and whatever eyepieces are used.

Fortunately you don't come across such scopes very often but I've seen a couple that were just unuseable.

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But there is such a thing as a poor telescope. If the objective lens or primary mirror is badly figured then it's simply not going to reach sharp focus whatever collimation adjustments are made and whatever eyepieces are used.

Fortunately you don't come across such scopes very often but I've seen a couple that were just unuseable.

OK -- then I would suggest trying the scope with an eyepiece otherwise you have no idea whether it is good or bad.

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I've acquired a number of really dodgy scopes over the years. Some I have split in half so that I can show people how scopes work. Some I have made myself so that I can show people just how bad Galileo's first scopes were.

................................................ the fact that I've played with really bad scopes and got something out of it makes me think I should just give them some of the spare Plossls I've acquired over time and suggest they try it. So what would you suggest? Make best use of bad equipment or cut their losses and get something halfway decent?

If it were me, and it was a different time, I would try to make the best use of bad equipment.  All it takes is a spark to start a fire in the mind, and a life long interest.  A lot of us grew up having to make something out of nothing, myself included. I think I was the poorest kid ( material wise ) in my neighbourhood, and remember having a trike with only one pedal, really.  My first telescope was a small used refractor with missing parts, but it showed me things I had only seen in a book, quite a thrill for a kid fifty years ago; but then, nowadays people want instant gratification, or they move on to something else. Sadly today there is a point of diminishing returns for ones efforts.

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I started off with a £60 3" reflector and I was amazed at some of the things a saw! You could take them somewhere dark with their telescope and one of your own telescopes that was a similar price and would be a likely replacement for your friend's. Then they can see the difference and make their own minds up.

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JNB has been given it so no cost, sounds like he has a few spare plossl's so again no cost.

To my thinking it is simply something to play about with, clean, paint, adjust whatever and see what improvement can be accomplished. It is likely not going to wipe the floor with a 10" OOUK reflector, but so what.

It is what is generally defined as "A bit of fun".

Improve it, if possible, then either give it back or find some youngster that would like a scope to look at the skies but cannot afford one.

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 It's someone else's scope and they don't have my experience the question is what could they best do with it.

Use it for terrestrial viewing would be my suggestion.

Astronomical observation is the severest test possible for optical gear: telescopes, binoculars, telephoto lenses. However these often produce perfectly acceptable results when deployed to uses that aren't sensitive to their limitations.

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I feel your pain.

Age nine i had for christmas a 30mm objective diameter singlet refractor with a singlet fixed eyepiece these were set in a pvc tube focussing was by sliding another pvc tube within the other ,um very un-precise ,it was mounted on a pillar claw mount attatched to the main tube by holes drilled into the tube the range of up down movement was 10 to 20 degree's the alt-azimuth claw was 1 inch bigger than the tube dia and the tube was 3 feet long ,so almost impossible to use .

Did it put me off astronomy NO!!  Did i learn from this negative experience , NO !!

iT'S come full circle and history has repeated itself ,all these years later ,i have a long focus refractor ( very unfashionable these days)  on a non goto  un- computerised mount .

So by any modern definition ( it was made in 1992 )  it's a poor scope .  But i use it and enjoy it and for me that's all that matter's really .

So what is it  . An  ASTROPHYSICS  180 EDT ON AN ASTROPHYSICS 1200 QMD MOUNT . 

So i'm making good use of what is and old scope with an dinosaur f9 focal ratio on a stepper motor non goto mount , more of the same ,Hell no , i think i'm making good use of my old poor scope :grin:  :evil:  :tongue:

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............................... history has repeated itself ,all these years later ,i have a long focus refractor ( very unfashionable these days)  on a non goto  un- computerised mount. ...................i use it and enjoy it and for me that's all that matter's really . ...........................

+ 1

I'm sure my equipment with setting circles is also considered unfashionable, but I'm happy with my old school choices.   :smile:  

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I feel your pain.

Age nine i had for christmas a 30mm objective diameter singlet refractor with a singlet fixed eyepiece these were set in a pvc tube focussing was by sliding another pvc tube within the other ,um very un-precise ,it was mounted on a pillar claw mount attatched to the main tube by holes drilled into the tube the range of up down movement was 10 to 20 degree's the alt-azimuth claw was 1 inch bigger than the tube dia and the tube was 3 feet long ,so almost impossible to use .

Did it put me off astronomy NO!!  Did i learn from this negative experience , NO !!

iT'S come full circle and history has repeated itself ,all these years later ,i have a long focus refractor ( very unfashionable these days)  on a non goto  un- computerised mount .

So by any modern definition ( it was made in 1992 )  it's a poor scope .  But i use it and enjoy it and for me that's all that matter's really .

So what is it  . An  ASTROPHYSICS  180 EDT ON AN ASTROPHYSICS 1200 QMD MOUNT . 

So i'm making good use of what is and old scope with an dinosaur f9 focal ratio on a stepper motor non goto mount , more of the same ,Hell no , i think i'm making good use of my old poor scope :grin:  :evil:  :tongue:

Another member of the Retro Astro brigade. My newest 'scope is my oldest

Richard

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