#1  
Old 01-04-2019, 04:05 PM
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xelasnave
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GSO ( similar) 8 inch f5.

There are a few of us using or have used a eigth inch and some very revemt recent purchases ( mmm.what improvements things to buy after intial work out and most happy with the general abilities of this cheaper range of scopes in terms of bang for your buck...well I am a fan...such a perfect size...and gathers light better than a dark patch.

So I have plans as to how to improve my GSO and wondered what others thought of the plan or what they may be doing to their scope.

I get obsessed sometimes but this is the backed off plan. ☺☺☺...the tube needs a strip down the seam ..a 40 mm x 2 maybe three mill...go overboard...a 4 inch by half an inch milled to fitt the internal curve..add small raised molding of structural x pattens...add interal baffles close..made of cardboard (selected for ease of fitting by cutting syrips with section cut out to accomodate the internal curved surface...paint them with resin...maybe a fine chop of glass..heck lets just do a carbon fibre one...which case paste the carbon fiber to the card board wike up could use alone...resin that up how rigid would it be...but I thought first to add eigth of an inch ply encased in fibre glass panel under the focuser to give it a solid base...in fact a section in effect of a ply x sectional approach glassed in linking the mounting plate to both the mirror and focuser section..carful thought to the x pattern could replicate a truss reflector .....that should be solid ...in the final coat of resin to the cardboard baffles or carbon fiber and cardboard...you add a sprinkling of saw dust.which would be great for strength you could think well now you could do another coat of resin or give give it its first coat of paint..any coloir so long as it is black although I have wondeted could you find a colour that works against stray city band light.
The baffling to me is so important..Point a scope near Sirrius both with and with out baffles and I but the diffetence would be dramatic. .elliminating side light really helps in my view...look at how Hubble take the baffles past the secondary optics. which means the tube needs to be extended or a removal unit in place that is in effect a baffled dew tube...
The focuser can slop around and I swear it can fall out..I havent tried but it needs attention...I have thought of adding additional rollar bearings...but I cant at the moment recall the things that turn it into a great focuser...but thinking about it even if you added blocks of wood to stop the slop you are miles ahead☺ but a good unit for what it is. I seem to get a focus and when you tighten it in it goes off...takes a bit of a juggle I find because of that...I realised today with poor scope that has fungus that I can fix its focuser by glueing it in place at a particular region and focusing using rings or slider tubes ..teadious but that would take the focus problem off the throw away list...so I may set that up..and given the mold see just how effective light frames and software can make a dead duck fly.
I am thinking the Sun and Moon ..its an old 150 mm refractor that shows the purple oceans on the Moon.
Today I am thinking should shoulder mount it add a dsle a finder sight and remote ...set the focus previous as you can't use a motor here mmmm maybe but the slop is a big issue anyways focus on infinity and tighten it shoulder it a shot away..I have shouldered it and it seem easy to add a shoulder bracket and finder scope..maybe binos with cross hairs...and a small gyroscope on top which should help to bag the international space station...hand held Moon shots maybe...surf photos..1200 focal length with a 2 x barlow and a 3 times barlow.☺☺☺..so the mold is not a worry that scope saw many miles..many many light years. .took me many places.
I will try and build a mold that hunts down the invading mold and eats it then leaves...I will need mold in box to give a place to move☺
when they have eaten the other mold..maybe pull the lens apart and see if it can be cleaned and reassembled☺
But I am off the track...what do you think can be done to make the eight inch f5 "hot".
Alex
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  #2  
Old 01-04-2019, 05:24 PM
Startrek (Martin)
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Alex
Sounds like a lot of work and money buying bits and pieces and design development to “turbo charge” or “hot up” your existing 8” GSO scope which may or may not produce the results your expecting ( a beginners only opinion )
My new 8” f5 Bintel GSO Scope only cost me $455 delivered to my doorstep and so far has exceeded my expectations beyond belief. It’s a quality scope with a great focuser for very little money and the only modification done was some better primary mirror springs which were fitted by Bintel
I’ve only images 3 objects over 2 nights in heavy light polluted Sydney and so far the results have been extraordinary. This scope will last me a life time for both visual and AP

By the way Alex I managed to image Centaurus A last night and will post it later on
Cheers
Martin
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  #3  
Old 01-04-2019, 06:20 PM
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ChrisV (Chris)
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Been using my GSO 8" f5 for nearly 2 years? I will upgrade to something classier one day but very happy with it now. I put a moonlite focuser on mine as I thought there was something wrong with the stock one (cost more than the scope). But I was probably wrong. Anyway the moonlite is nice to use especially now I've motorised it. It's also easy to tilt adjust - and there was substantial focuser tilt on mine.

The main mod was sticking an opaque shower cap on the back. Substantial light gets through there and I image from my back verandah which cops light from inside the house.

I should put an extra ring on the front of the scope to make it more stable.
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Old 01-04-2019, 06:26 PM
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xelasnave
Gravity does not Suck

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I am convinced baffling works and the baffled dew tube..I have not runba baffled dew tube on the eight but I have a two long one on the 80mm if nothing else it keeps out dew...
They are excellent value but I cant help thinking of things to do to it...there are things I have to do ...like just a little more counter weight..I have had to hang a bag of sand..got two small weight lifter weights which I will put in a new smaller hole .should be perfect.

But I am still trying to get a few things going with the 80 so the eight is not getting a good work out.
I should have been out there I rarely miss an opportunity cause there are so few.
Alex
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  #5  
Old 01-04-2019, 06:29 PM
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xelasnave
Gravity does not Suck

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Hi Chris...mmm I would like such a focuser. ...
And thanks for the showercap tip I had not thought of that...
Alex.
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Old 01-04-2019, 07:55 PM
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ChrisV (Chris)
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I must look into baffling Alex. Dew shield helped me with stray light.

I've also used stage light black foil - must get some more.
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Old 01-04-2019, 07:56 PM
raymo
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If you had a SW Newt you wouldn't need a shower cap. The back end is closed
so no light or dust from that end. I had mine close to eight years, and never felt a need to upgrade the focuser, other than fitting an SW motor kit.
raymo

Last edited by raymo; 01-04-2019 at 08:58 PM. Reason: correction
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Old 01-04-2019, 11:04 PM
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xelasnave
Gravity does not Suck

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I suppose the trick is to tighten the focuser and still have the motor drive it direct drive needed there. I have one ..maybe not tighten it and hold in place by the motor..well it cant go anywhere I guess..still some shims or something would not go astray.
I prefer the refactor method using gear and track. No image shift on lock down.
Anyways its managable.
Alex
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