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re-coating or to buy new


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I have had my Tal 2M 6 inch newtonian since 1998 and the mirrors have just about had it. (main has a scratch and foxing) I use my Skywatcher 127 mak/cass at the moment but I would like to get the old Tal back in commission because of the field of view aspect.  6 inch newts have come down in price these years and I was wondering would it be cheaper to buy another 6 newtonian or get the mirrors recoated.

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It would depend how good the mirror figure was to me. If it gave consistently good sharp stellar views without optical issue like astigmatism, turned edge etc, then it seems a shame to waste the old mirror. A scratch or two is not usually an issue, and it wouldn't cost much to get the mirror coated, give Galvoptics a ring for a quote.

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I think the TAL 2M has a spherical primary rather than a parabolic one ?

It works well though, from the example that I briefly owned a few years ago.

So does the Skywatcher 150 F/8 though and that is a parabolic primary:

http://www.nightskies.net/scopetest/scopes/explorer/150PL.html

I've seen the Skywatcher 6" F/8 for under £100 for the optical tube so thats worth bearing in mind.

 

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I had a 20 year old TAL2 the mirrors where still 100% scratch and stain free. I think there are very few modern newts that can stand in the shadows of the Russian. If I where in your place, I would have them checked and re-coated. You can always sell it for more than the coating job would cost. Sold mine for €250 complete with the pillar and clockwork and everything else that came with it when it was new, even the wooden boxes. The little guider scope is famous for it's quality as well.
 

TAL 2-1.JPG

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When I researched Tal 2 mirror sets I seem to recall finding a post that some replacement mirror sets available in Canada where parabolic...a few years ago I spotted 2 mirror sets on Gumtree and noticed the Tan/l 2 stamped onto the primary holder, anyways I acquired both mirror sets and 2 hand built wooden telescope tubes...I wonder if Peter Drew would make me a binoscope from 2 Tal2 mirror sets :icon_biggrin:, they do seem to be replacement mirror sets as there in their own small wooden box is there a simple test to determine parabolic or spherical?

$_86.JPG

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On 12/1/2017 at 10:05, Waldemar said:

I think there are very few modern newts that can stand in the shadows of the Russian.

There are quite a few very nice (and expensive) newts (Dobs) here in the states made with Zambuto, Lockwood, Kennedy, and Swayze primaries.  Even Galaxy, Pagasus, Nova, Lightholder, and Royce primaries run circles around what's commercially available.  Of course, the seeing here can be exceptional so they can achieve their potential that might go to waste in the UK.

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I got my great (Bought in 2000) GSO 200mm F/4 recoated. And the outfit I used had a very good reputation. And they would do the secondary for free. It came back great! I was asking the same questions, but I finally just 'rolled-the-dice.'

So I suggest you get references, "talk" with the person who owns the outfit, and see how YOU feel. If good - bring the old soldier back to it's best! Or risk having an agonizing, gnawing feeling of what could have been. One way - you wasted your £££'s. The other: Gone for good!

That's my 2¢,

Dave

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7 hours ago, Louis D said:

There are quite a few very nice (and expensive) newts (Dobs) here in the states made with Zambuto, Lockwood, Kennedy, and Swayze primaries.  Even Galaxy, Pagasus, Nova, Lightholder, and Royce primaries run circles around what's commercially available.  Of course, the seeing here can be exceptional so they can achieve their potential that might go to waste in the UK.

I agree Louis, but the keyword here, as you said is 'expensive'...

In the price range of the TAL you won't find anything to compare, so re-coating would give an above average solid Newtonian, I think.
the downside of the thing is of course it's weight. It is like a canon barrel... and a bit temperature sensitive...

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