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Knighty2112

Opticstar AR90S 90 mm short frac

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Hi all. Looking at possibly getting a secondhand Opticstar AR90S f5.5 short refractor, primarily to use with binoviewers, but also to use on my Goto mount I have, and possible in the future too for some EAA too perhaps.. Looks like quite a good quality scope so just wondering if any members have/had one and how it performed for you.

Cheers,

Gus :) 

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I think i had its for runner a 90mm darksky with sliding dewshield and single speed 2" crayford, it was one of the scopes i regret selling

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I'm using one as a finder on my 12" and often enjoy the wide-field view compared to the main scope. Well suited to the standard skywatcher 28mm 2" cheapie eyepiece for widefield use. As you would expect it runs out of steam at 3-figure magnifications but I've seen 4 belts on Juipter with it. . Metalwork rather good for the money. Not sure I'd pay the new price but can be a good s/h buy. 

RL

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get an ed80 Gus, great little scope, amazing optics for the money, i love mine, i use it on everything in the sky. charl.

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There's a 90mm f5.5 on ABS as we speak for £50.... I've seen the the chap on here, knows a thing or two about fracs, might be worth a look... 

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2 minutes ago, Fozzie said:

There's a 90mm f5.5 on ABS as we speak for £50.... I've seen the the chap on here, knows a thing or two about fracs, might be worth a look... 

Yeah, I've seen that one too. What is atracting me to the Opticstar scope is the claim it is binofriendly. Checked some of their other short tube fracs, and these state the need a focul reducer to work with binoviewers, but not this model apparently. Going to check it out tomorrow evening with the owner. The other plus also is that it has a Crayford dual speed 2" focuser too fitted to it. 

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25 minutes ago, rl said:

I'm using one as a finder on my 12" and often enjoy the wide-field view compared to the main scope. Well suited to the standard skywatcher 28mm 2" cheapie eyepiece for widefield use. As you would expect it runs out of steam at 3-figure magnifications but I've seen 4 belts on Juipter with it. . Metalwork rather good for the money. Not sure I'd pay the new price but can be a good s/h buy. 

RL

Plan to possibly use it as a quick grab and go scope mostly, and possibly also on my Skytee with either my Startravel 120mm or Starwave 102mm frac so I can enjoy widefield views too, along with more power from the other scopes.

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25 minutes ago, xtreemchaos said:

get an ed80 Gus, great little scope, amazing optics for the money, i love mine, i use it on everything in the sky. charl.

Good idea Charl, but need to budget to a certain limit for now, unless a good second hand one comes up at a good price. :) 

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37 minutes ago, nightfisher said:

I think i had its for runner a 90mm darksky with sliding dewshield and single speed 2" crayford, it was one of the scopes i regret selling

Thanks for your feedback Jules. It certainly looks a quality little scope! :) 

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Hi Gus, this is the exact scope I have with my Nexstar SE mount. I've only used the combo once so far, it showed me M27 as a clear apple core using direct vision and resolved M15 which is pretty good going for a 90mm frac with my skies, I concluded the contrast must be very good. Bright stars do show a bit of halo but it's f5.5 so I actually expected it to be worse. The build is fantastic like a mini Tal but with a better dew shield..

I'm very interested to hear that it could be BV friendly :)

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12 minutes ago, Chris Lock said:

Hi Gus, this is the exact scope I have with my Nexstar SE mount. I've only used the combo once so far, it showed me M27 as a clear apple core using direct vision and resolved M15 which is pretty good going for a 90mm frac with my skies, I concluded the contrast must be very good. Bright stars do show a bit of halo but it's f5.5 so I actually expected it to be worse. The build is fantastic like a mini Tal but with a better dew shield..

I'm very interested to hear that it could be BV friendly :)

Thanks Chris. Didn't realise that was the scope you got to replace the 4SE I bought off you. I'll let you know if the binoviewer works with it. If it does OK I'll get it. 

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ah i was going by the AR90S new price, and the ed is £60 more, but thay do come up from time to time, ive see them go for as little £200 2hand. but the AR90S looks to be a nice scope. goodluck on you new buy. charl

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Drove down to Sheffield to check out the scope this evening. Sadly, although the the scope is nice, I still needed to use a the 1.6x Barlow nosepiece that came with the binoviewers when using any diagonal to achieve focus. So alas just a 0.4x gain over using the 2x nosepiece with my other scopes is not really worth the price of this scope even at second hand price really. Shame as it was very nice quality.

Seriously looking next year maybe to cut down my ST120 to be able to achieve a widefield binoviewer scope. Watch this space! :) 

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On 10/8/2016 at 21:30, Knighty2112 said:

Drove down to Sheffield to check out the scope this evening. Sadly, although the the scope is nice, I still needed to use a the 1.6x Barlow nosepiece that came with the binoviewers when using any diagonal to achieve focus. So alas just a 0.4x gain over using the 2x nosepiece with my other scopes is not really worth the price of this scope even at second hand price really. Shame as it was very nice quality.

Seriously looking next year maybe to cut down my ST120 to be able to achieve a widefield binoviewer scope. Watch this space! :) 

Hi Gus, i see you ended up getting an AR90s, how do you rate it and do you think it would work well on the star discovery

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4 hours ago, nightfisher said:

Hi Gus, i see you ended up getting an AR90s, how do you rate it and do you think it would work well on the star discovery

Hi Jules. Yes, I ended up getting one just to use as a small grab and go refractor. I sold my binoviewers, so don't need to worry about them with this scope. As to the scope itself it is a good scope, nice quality build, and nice and light in weight too, so I don't think you would have any issues with it on the Star Discovery goto mount. Only issue I have is at above a certain angle, and with heavier EP's, diagonals etc the dual fine focus on the scope doesn't work well. Normal focus is fine though. In reality this is no big issue for me as I can still get correct focus OK with the normal focus wheel. If I were to score it out of 10 I'd give it an 8.5. Views are nice through it, with the defects in CA with the f5.5 ratio on it as you get in other fast scopes too. Overall a very nice quality little scope for the price methinks. 

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Thanks Gus, this is a rehash of the old Starsky 90 i had a few years back and it performed well for an achro, i have placed an order for one

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