OpticStar AR90 S Gold, Achromat

[lensman57]

Hi,

Following my very positive experience at the OpticStar shop at Sale, Manchester 4 weeks ago when I purchased my SW127 Mak , I purchased the OpticStar AR90 S Gold Achromat OTA today. I intend to use it as a travel scope and for the casual widefield viewing on my AZ SynScan GoTo mount ( the Mak is on an EQ5 Pro GoTo mount now), further down the line it will make a brilliant guide scope for DSO imaging if I ever get the fever and the finance for it. I can only comment on the mechanical construction of the tube so far and in one word it is outstanding. It has a super smooth 2" double speed 1-10 crayford focuser, the dew shield is a beautiful retractable and precision fit aluminium affair and the lens cell and the focuser are screwed in to the tube and not fixed by screws , the whole thing really feels and looks good and inspires confidence, even the lens cap is anodised Aluminium and it screws on to the end of the shield. If the optics are anything like the mechanical bits then I am on winner at just a shade over £200.00. My only gripe is the less than friendly tube rings that require a hex key to rotate rather than thumb wheels but then again once it is adjusted it should not require rotating anymore particularly on an AZ mount. if the skies are clear tonight I will give it a go and see how the optics perform.

Regards to all,

A.G

[nightfisher]

I have the older version, it was sold as a starsky 90, and has a single speed crayford, its a good scope but might be on the "to sell" list, i got it for widefield and some very basic AP, but dont get a chance to use it

[lensman57]

I have the older version, it was sold as a starsky 90, and has a single speed crayford, its a good scope but might be on the "to sell" list, i got it for widefield and some very basic AP, but dont get a chance to use it

Hi,

Well I had a chance tonight to give it a go. First I mounted it on the AZ SynScan GoTo mount, and aligned it using two star alignment. At 7.30 pm there was just about visibilty to see jupiter and I slew towards it. The mount got it dead center for a change and it was a nice image, using a 15 mm BST both bands could be seen and I am sure I caught a glimpe of a dark patch on or very near one of the bands during fleeting moments of good seeing, the poles showed slightly darker shade of the ivory colour and the four moons were lined up in a straight line either side, very nice. There is a little fringing but once the focus is dead on most of the CA goes away. The EPs have lot to do with it, the 9 mm Celestron XL, the 15 mm BST starguider and the 6 mm TMB showed very little if any fringing, the other EPs showed some but not distracting. I stayed out hoping that the haze and the orange glow go away and at 9.30 they nearly did so I started hunting for M31, M81, M82, and some of the other clusters that are visible from my back garden. As a whole it was a very enjoyable experience and I am sure given real dark skies and good seeing the scope will give some really nice views of the skies. The stars appeared sharp and contrast was very good indeed, what I really liked was the wide field of view compared to my 127 MAK, but for planetary at high MAGs the 127 will win everytime. Tonight given the less than favourable seeing conditions the best views were from the 15mm BST on the clusters, and 9mm Celestron XL on Jupiter, a very good observing session. BTW for some reason the mount worked very well with this scope, much better than with the 127 MAk, it maybe because of the reduced weight of the scope cpmpared to the MAK.

Regards,

A.G

[John]

Nice report of what is obviously a great little scope A G

Having a quick-to-cool widefield scope to compliment your mak-cass is a good combination. Treat it to a 2" wide field eyepiece and a UHC filter for the Summer and you will get a lovely view of the Veil Nebula

[lensman57]

Nice report of what is obviously a great little scope A G

Having a quick-to-cool widefield scope to compliment your mak-cass is a good combination. Treat it to a 2" wide field eyepiece and a UHC filter for the Summer and you will get a lovely view of the Veil Nebula

Hi John,

Many thanks, I just used the 1.25" dieelectric diagonal from my MAK tonight, BTW I forgot to mention that I used a Badder neodymium filter on the EPs tonight to help get rid of some of the horrible orange glow that surronds my back garden, I noticed that there was a marked difference while viewing M81 and M82 as these were almost at the zenith, the filter somehow made the background darker making the faint glaxies stand out a little more.

Regards,

A.G

[Alkaid]

Hi Lensman,

This is just what I'm looking for, I recently posted about some widefield achro's from Telescope Service, but now I know I can buy from the UK I think I will get one of these instead...

I would love to see a few pics of this scope set up on your mount if possible please?

Thanks Steve