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I owned a couple of these - they are exactly the same as the Skywatcher ED80 apart from the colour scheme (personally I like Orion's dark grey metallic).

Nice little scopes, very well colour corrected.

John

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I've owned a blue Skywatcher version and it was a great little scope, held up to about x170 on planets on a good night. Its a bit "no frills" in these days of sliding dewshields and dual speed Crayford focusers but optically they are very good.

Another vote for the Orion paint job as well....:)

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I'm a great fan of these, cracking 'scopes for the money. Well corrected and a pretty flat field for imaging. As John says, the Orion is the same as the gold-tube Skywatcher, ISTR that the blue-tube is FPL-51 glass rather than -53 but there's precious little difference there in practice.

Focuser is a bit prone to slipping under load, but generally easy to fix up.

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Ben, both the blue and the gold Skywatchers were optically identical. Both used FPL-53, the new paint job was just a 'rebranding' exercise to distance the ED range from Skywatchers existing line of achros

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I have an Orion ED80 mounted on a dual bar side by side with a SW ED80pro. The optical preformance of the Orion is as good as the SW and both show clean diffraction rings at high magnification.

Don't undertand why the Orion OTA is lighter than the SWED80, but you can notice the difference when balancing them.

All in all the Orion is a good telescope, the focuser doesn't have the second locking screw that the SW has, but no big deal. ( BTW I have a 2" TS Crayford which I'll probably fit to the Orion - only to improve the 2" connection for the spectroscope)

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Ben

How do you stop any slippage of the focuser if for instance imaging with a DSLR on something near to the Zenith.

I see that the focuser has a tensioner screw but will that stop slippage if fully tightened up ?

Graham

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I think there's a fair bit online about the 80ED focuser, the issue is that the flat friction surface of the focuser drawtube isn't quite flat, and it's just a case of sanding it down a bit. There a bit variable though, some suffer quite badly - my first one did, and couldn't hold a 2" diagonal/eyepiece without slipping until I fixed it - but later ones seem much better.

Ben, both the blue and the gold Skywatchers were optically identical. Both used FPL-53, the new paint job was just a 'rebranding' exercise to distance the ED range from Skywatchers existing line of achros

Ah, that would explain why I could never see a difference then! I'd always thought that the glass changed along with the colour scheme.

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I love my ED80 every time I use it. Take magnification well too, up to 230x some times when seeing allows. The focuser on mine was pretty good to start with, but after a while I added a teflon shim to the tensioner screw and that made it just about perfect. Holds the 2" diagonal and Pentax XW30 at zenith no problem

Seriously good 'scopes.

Ant

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Guys,

I've never had a "blue" Skywatcher, only the "Gold" EDpro.

Checking the ads on the back cover of the Practical Astronomer, it clearly states the EDpro uses FPL-53 fluorite glass for the rear element, by inference the "standard" ED doesn't have this glass????

The Orion adverts also mention FPL-53, as do the new Skywatcher "black Diamond" adverts....

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I thought fpl53 was mentioned when the blue ED80's first came out - not sure though. I assumd all ED80 versions had it. I certainly don't have a problem with CA in mine (blue tube).

<shrugs and wanders off...>

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  • 2 years later...
  • 1 year later...

So the Orion ED80 is optically identical to the SW Evostar ED80 then? And an Orion will match my Evostar and take a SW 0.85x FR/FF intended for the SW ED80?

Edited by Gina
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I have one and I have to says it's a brilliant scope for the money. Mine doesn't seem to have a focuser issue, and takes my Nikon D300 (heavy) without wilting.

In the original US review, the comment was made that they could see Cassini all the way round, which matches my own experience (when Saturn is tipped at the right angle of course!). It has given me some lovely views of Mars, Uranus and Neptune as well, and shows impressive detail on Jupiter, additionally resolving at least two of the moons as clear disks.

It resolves doubles very well at up to x160, and has given many a viewer a superb view of Epsilon Lyrae within a couple of minutes of getting the scope out - the cool-down time is very fast.

Downside: It's only 3".......what do you expect!

Chris

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So the Orion ED80 is optically identical to the SW Evostar ED80 then? And an Orion will match my Evostar and take a SW 0.85x FR/FF intended for the SW ED80?

Yep , you can use the skywatcher FF/FR on the Orion 80ED. Its pretty much exactly the same telescope, except with a more basic focuser (which is why the weight is different). I know you're looking for a 2nd 80ED, so I think its best you stick with an exact duplicate. No big difference in price really, but it wont look as nice as two black diamond refractors :)

But back to the OP. The 80ED is fantastic and pretty much unbeatable for its price (which is why I have two!). Visually, it barlows very, very well. For imaging, its about the most reliable telescope you could hope for, just put it on the mount and it works with no fuss whatsoever.

The only weak point is the focuser - while its good enough to hold a DSLR (0.5kg), it will start to struggle a bit when you bung a reducer, FW and CCD on it. Thats fixable though, just tweak the tension a bit using the screws on the underside of the focuser. The focus also sometimes drifts a little when you lock the focuser, so you need to keep an eye on that (easy with a B-mask) - the best way to manage the situation is to focus on a bright star which is at a low(ish) altitude. That way, the focuser isnt fighting against gravity when youre twiddling the fine focus knob.

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Hi Guys,

When a company advertises their scope is ED Doublet, it means that only one of the elements, typically the rear one is made of ED FPL-53 glass. Just so you all know, I have learnt that it is not just the type of glass that makes a good optic. Good ED glass only corrects the color, but it is the Strehl Ratio that does the Quaity job. Not many companies out there give the Strehl ratio. Typical telescopes like the ED 80 are diffraction limited most times, but have a strehl of only 0.85 to 0.89. Good scopes like expensive triplets have a strehl of 0.9 to 0.93. Good need not be expensive, just need to know where to find stuff. Original A&M used to have strehl varying from 0.95 to 0.98, which is practically perfect. If someone advertises their scope as 0.9999, the he is most likely making a dunce out of you. :)

Regards,

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ED can be FPL-51 and an assortment of Russian and American glasses also, LOS lens use OK-4 and are amongst the best available.

FPL-53 is just a name probably trade marked for the Ohara glass company.

It is not just FPL-53, and even amongst Ohara it is not just FPL-53.

Not sure about the use of the term Diffraction Limited either, I doubt that any scope is operating at the diffraction limit as that implies perfection in their optical properties and as the lens are spherical that means they are non-ideal so not operating as ideal optical components. An ED scope will have 2 components and that means just 2 wavelengths at the same crossing so again use of the term "Diffraction Limited" is dubious as the term refers to what would be a perfect lens.

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Not sure about the use of the term Diffraction Limited either, I doubt that any scope is operating at the diffraction limit as that implies perfection in their optical properties and as the lens are spherical that means they are non-ideal so not operating as ideal optical components. An ED scope will have 2 components and that means just 2 wavelengths at the same crossing so again use of the term "Diffraction Limited" is dubious as the term refers to what would be a perfect lens.

Maybe a way of saying "meets or exceeds Dawes limit" - mine certainly does.

Chris

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