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Old 28-05-2017, 09:15 AM
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that_guy (Tony)
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I received a dud!

Hi guys, some of you may know that I recently purchased an 8" CF GSO Newt astrograph from andrews. All seemed well until i took it out for the first time to a dark site with the astroanarchy crew. The camera wouldnt focus! I thought it was a bit weird that when I was aligning my telrad that the eyepiece didn't need an extension tube (it was supplied with the telescope under the assumption youd need one). than when i attached the camera to the telescope, there wasnt enough in focus. Now I understand that visual newts have this problem but I bought this with the intention to image since it was designed for dslr photography (f/4 carbon fibre, dual speed focuser and all). Noone at the star party could figure it out! Astropete was there from astropete cafe but even he was stumped. There should be no reason it shouldnt be focusing. There were a couple of people there that had the same type of scope from GSO (steel not CF but same design) that had no problem with in focus. Ive also read reviews on this scope that people said had no problem reaching focus for dslr. The dslr i used was a canon 500d so its not the problem there. So I guess my question is this, is this something I can fix (for relatively cheap or free) or would it be easier to return it to andrews and receive a refund/replacement.
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Old 28-05-2017, 10:21 AM
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doppler (Rick)
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If the infocus needed is not too excessive maybe the collimation screws on the primary are wound in tight and you can move the mirror forward a bit that way. The tube etc would be made all the same so maybe the mirror is not f4 but slightly longer? Best to ask Andrews for advice, you shouldn't have to do anything other than collimation to a new scope.
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Old 28-05-2017, 10:23 AM
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Quote:
Originally Posted by doppler View Post
If the infocus needed is not too excessive maybe the collimation screws on the primary are wound in tight and you can move the mirror forward a bit that way. The tube etc would be made all the same so maybe the mirror is not f4 but slightly longer? Best to ask Andrews for advice, you shouldn't have to do anything other than collimation to a new scope.
We tried this at the star party, we moved up the mirror as far up as we could usign the collimation screws but the focus was still so far off that you could see the secondary mirror
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Old 28-05-2017, 11:38 AM
raymo
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My guess is that if you can't get near focus with the collimation screws fully wound in, that it has been fitted with an f/5 mirror by mistake.
raymo
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Old 28-05-2017, 11:45 AM
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Quote:
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My guess is that if you can't get near focus with the collimation screws fully wound in, that it has been fitted with an f/5 mirror by mistake.
raymo
yeah thats what everyones guess was as well
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Old 28-05-2017, 11:50 AM
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doppler (Rick)
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A couple of years ago I got a replacement f6 mirror for my 8" newt, and had to move the primary up the tube to get focus because the replacement mirror was a bit less than f6, maybe f 5.9. I am guessing that this is the case with your scope and it was only tested ok for visual. It might be a really good mirror optically and extra fast f wise but you really don't want to be modifying anything to test it or you will void warranty.
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Old 28-05-2017, 12:40 PM
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OzEclipse (Joe Cali)
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Even if you can't reach focus, moving the eyepiece in an out should tell you where the focus is - further out or further in. The other way is to lay the tube down on the floor. Using a torch and a piece of thin paper held at the same distance find the point where the torch projects a focused image onto the paper. This is twice the focal length. It is twice the focal length, so about a full tube length from the end of the tube.
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Old 28-05-2017, 12:40 PM
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Ahhh, all you had to say was Andrews and it all came to light.

Leon
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Old 28-05-2017, 12:46 PM
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Ahhh, all you had to say was Andrews and it all came to light.

Leon
I guess they should have checked the focus before shipping but i think its just gso manufacturing thats at fault more than anythign else
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Old 28-05-2017, 12:56 PM
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Ahhh, all you had to say was Andrews and it all came to light.

Leon
Leon,
That's a cheap shot and really unnecessary. It sounds like he hasn't approached Andrews about a warranty fix or replacement. They are selling a GSO assembled boxed scope. No reason for them to assemble and test every scope. GSO have a good rep. Accidents happen. Why don't we give Andrews a chance to fix it. if he can go to them with an accurate description of where the unreachable focus is, in or out, it will allow them to work out what to do quickly.
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Old 28-05-2017, 12:59 PM
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I recall on an earlier thread that you were wondering why these CF newts were so much cheaper than elsewhere, maybe a dud batch ok for visual but not setup for photography. Still you are entitled to a replacement that works as advertised.
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Old 28-05-2017, 01:12 PM
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that_guy (Tony)
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yeah its fine, its just that i cant call or contact them yet seeing how its the weekend, its the first thing on my to do list tomorrow.
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Old 28-05-2017, 07:20 PM
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Joe please don't lecture me, my experience with Andrews was horrendous about an order that they clearly stuffed up.
They were un repentant and it was proved that they actually were in the wrong.
Accept responsibility, not a chance and sent me abusive letters, which i still have.
If I posted those letters on IIS I would be banned, so bugger off.
I would not recommend that company to anyone.

Leon
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Old 28-05-2017, 08:32 PM
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It can't be a F5 mirror by mistake, that would put the focal point 200mm further away from the focuser. More likely they gave Tony a F3.8 mirror which would be 40mm too short.
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Old 28-05-2017, 08:33 PM
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gaseous (Patrick)
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Tony, I was next to you last night with my 16" dob, and I don't know how you maintained your composure - you seemed to be there for hours trying everything to get that damn scope sorted. I hope you get it resolved quickly!
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Old 28-05-2017, 08:42 PM
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that_guy (Tony)
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Quote:
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Tony, I was next to you last night with my 16" dob, and I don't know how you maintained your composure - you seemed to be there for hours trying everything to get that damn scope sorted. I hope you get it resolved quickly!
When you have a dark sky and great company, its hard to stay annoyed at things you can't control
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Old 29-05-2017, 03:16 PM
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the couriers picked it up from my house, will keep you guys all updated on the process, whether i can get a replacement or a refund
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Old 29-05-2017, 05:10 PM
raymo
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You are obviously quite right Bill; I don't know what I was thinking.
It just occurred to me as a likely scenario, so I posted it without
thinking it through.
raymo
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Old 29-05-2017, 05:58 PM
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Leon , that may be your dealings with them , I myself have had nothing but great service from them , and it looks like Tony is as well .

It will be sorted .

Brian.
Quote:
Originally Posted by leon View Post
Joe please don't lecture me, my experience with Andrews was horrendous about an order that they clearly stuffed up.
They were un repentant and it was proved that they actually were in the wrong.
Accept responsibility, not a chance and sent me abusive letters, which i still have.
If I posted those letters on IIS I would be banned, so bugger off.
I would not recommend that company to anyone.

Leon
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Old 29-05-2017, 06:43 PM
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Thanks Brian,
I do remember your generosity in the NT.

Leon
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