Oooh Aaahh! First look at GSO 8" RC..

[bluescope]

Originally Posted by gregbradley

Gee that looks nice and a case as well!

I like the baffled tube. My RCOS didn't have that. I see some nasty reflections off bright stars on some RCOS images.

Looking forward to some images.

What is the focal length and F ratio?

Fixed primary and collimatable focuser could be a good thing.

Carbon fibre tube is nice. How much do they cost?

Greg.

Here it is Greg ... I just checked too

http://www.andrewscom.com.au/site-section-10.htm

[AlexN]

Thanks for the comments guys.. First light should **SHOULD** be tomorrow night, all things being equal though, it will probably dump rain tomorrow, and all weekend!

Wayne - Thanks mate, I appreciate the heads up, at the moment im in the middle of organising a modded 30D through Eric, should that fall through for any reason, I'll get on to you straight away..

Greg - the scope is an 8" F/8 @ 1624mm. The scope cost me $2495. Should the optics preform as they are supposed to, I think this will be a great scope.. awesome bang for buck..

The only way I could see the fixed primary as a bad thing is if 1.) the scope was dropped skewing the rear cell (which would have to be a nasty drop) or 2.) whatever is used to fix the mirror in place has poor thermal expansion qualities... There would be no need for the CF Tube and Quartz optics should the mirror fixing setup cause the mirror to change shape or be moved due to expansion..

Both of those things Im sure GSO thought about... Im not quite ready to pull the scope apart and find out how its all put together JUUUUST yet!

[Satchmo]

Originally Posted by AlexN

The scope cost me $2495. Should the optics preform as they are supposed to, I think this will be a great scope.. awesome bang for buck..

Hope it doesn't have the same level of surface roughness as the two scopes independentaly tested on the German website. Those guys must have been incredibly unlucky receiving two lemons to test.

Mark

[matt]

Originally Posted by AlexN

Thanks for the comments guys.. First light should **SHOULD** be tomorrow night, all things being equal though, it will probably dump rain tomorrow, and all weekend!

That's pretty much the forecast, mate Showers, anyway.

Ah well....think of how clean the air will be when you finally get to point that beauty at the sky

[gregbradley]

Greg - the scope is an 8" F/8 @ 1624mm. The scope cost me $2495. Should the optics preform as they are supposed to, I think this will be a great scope.. awesome bang for buck..


Thanks Alex.

Incredible value.

Greg.

[jase (Jason)]

Is the sky clear yet? Keen to see how quality control has stacked up with this scope. Looking forward to seeing the first light image.

[Zaps]

Originally Posted by Satchmo

Hope it doesn't have the same level of surface roughness as the two scopes independentaly tested on the German website. Those guys must have been incredibly unlucky receiving two lemons to test.

Mark

Yes those results have me worried too. I'm hoping they both got early examples which were basically prototypes, and that production versions now have the figuring sorted.

[Vader (Valery)]

Originally Posted by Zaps

Yes those results have me worried too. I'm hoping they both got early examples which were basically prototypes, and that production versions now have the figuring sorted.

There is no real hope that other newer samples will be even a bit better.
These tested scopes has very good spherical aberration correction - in other words, we see, that the systems were figured. The bad microrelief is the
result of figuring technique. Such systems has very high aspherics
gradients, especially on secondary mirrors. It is quite difficult and time
consumption to make such aspherics smooth. Any fast metods will cause
such rawdness of surfaces resulting very poor energy concentration
and really no diffraction images.
If these cheap RC scopes will be tested with interferometer where it's camera has large
scale frame, with processing of several thousands reference points,
the results of optical quality will be even worser.

There are no fast and cheap ways to make such aspherics smooth.
Therefore all really good R-C telescopes are expensive.
If an 8" RC scope is going for $3000, then don't expect real quality.


VD

[White Rabbit]

Wow, way to go, raining on the guys parade. Let him at least get it out of the box and play with it before you slam it.

[gbeal]

Originally Posted by White Rabbit

Wow, way to go, raining on the guys parade. Let him at least get it out of the box and play with it before you slam it.

Yes, I agree, let him enjoy the moment, and in some respects until we have some images all this good or bad is conjecture anyway.
Go Alex.

[AlexN]

Cheers White Rabbit and Gary, I appreciate the support on this.. Unfortunately, the scope still hasnt met the mount, due to prior commitments and weather.. Once I've taken some images I'll be glad to hear everyones opinions, Until then, the speculation that the scope will be a dud is perhaps a little premature... I don't know if anyone else has found one, but im yet to see a review of a final production model of this scope...

Fingers crossed for first light THIS weekend.... Might have to suffer a horrible day at work if we get a stunning night during this week.. I dont think I can hold off any longer!

[Matty P (Matt)]

Awesome stuff Alex! It looks like a great scope for the price. I'm really interested to see what it can produce. Can't wait.

Good luck with weather this weekend.

[Zaps]

Vader=VD=Valery Deryuzhin at Aries Optical, a competing vendor and known hater of Chinese made telescopes which threaten to eat his lunch? Not an objective opinion maybe?

Pardon me if I'm wrong.

Originally Posted by Vader

There is no real hope that other newer samples will be even a bit better.
These tested scopes has very good spherical aberration correction - in other words, we see, that the systems were figured. The bad microrelief is the
result of figuring technique. Such systems has very high aspherics
gradients, especially on secondary mirrors. It is quite difficult and time
consumption to make such aspherics smooth. Any fast metods will cause
such rawdness of surfaces resulting very poor energy concentration
and really no diffraction images.
If these cheap RC scopes will be tested with interferometer where it's camera has large
scale frame, with processing of several thousands reference points,
the results of optical quality will be even worser.

There are no fast and cheap ways to make such aspherics smooth.
Therefore all really good R-C telescopes are expensive.
If an 8" RC scope is going for $3000, then don't expect real quality.


VD

[netwolf]

Congrats Alex and best of luck with your new scope. I for one am optimisitic that yours will perform better than others in the past.

[Chippy (Nick)]

Originally Posted by netwolf

Congrats Alex and best of luck with your new scope. I for one am optimisitic that yours will perform better than others in the past.

Me too!!!

[Vader (Valery)]

Originally Posted by Zaps

Vader=VD=Valery Deryuzhin at Aries Optical, a competing vendor and known hater of Chinese made telescopes which threaten to eat his lunch? Not an objective opinion maybe?

Pardon me if I'm wrong.

You are right guessing whom I am. But no more.
I just explained, that there is no real hope, that next samples of these
8" RC will be better made optically. They can be improved in the
mechanical design, focurer, outside style etc. They can't be improved
optically - because of nature of these things. High gradient aspherics
CAN'T be made fast and cheap. Again: high gradient aspherics
CAN'T be made fast and cheap.
The same was with attempts to obtain very smooth optics in fast made
SCT. With some variations they always suffer of surface roughness.
But they suffer less, than these cheap RC.
Even spherical optics being fast made are not smooth at all - zones,
surface roughness etc. What we can expect from $1395 RC where
aspherics is really huge?
If you don't believe, no problem, you can check if your guess is right -
that next samples will be significantly better than tested crap ones- just
buy one of later sample and look yourself.

And why these scopes were dropped from $3000 to just $1395 ?
I can tell you - they are really crap. They are MUCH worser than even
RCX from Meade! RCX are coma-free design of SCT and their optics is
way smoother, than fast cheaply made taiwanese RC.
If you like to pay your backs for a magical "RC", do it. But others, I believe, have all rights to know what is what and make their choice with open eyes.
As a person, who know this subject, I can't recommend to buy cheaply
made RCs. Peoples will spend their money much wiser buying Meade RCX.
They are not a high-end RC, of course, but they are definitely better, than cheap, crap taiwanese RC.

[toryglen-boy (Duncan)]

this is all getting a bit strong, aint it?

just let the guy enjoy his scope .... jeez

[avandonk]

From just looking at the detail of this scopes construction, all very good in my opinion, I hardly think the manufacturer would then NOT install optical components that at least match the rest of the scope. Obviously only a test will tell. It all looks very good to me. Just don't rush the test Alex as it will take time to optimise everything. If I had it in my hot little hands I would be itching to try it out too!

Hope the weather is kind to you.

Bert

[White Rabbit]

Yeah, theres no pressure to produce stunning results on the first night or anything lol.

Just enjoy the scope it has to be better than my 8" GSO newt that cost me $300, brand new rolf.

[matt]

If only these danged forecast showers and cloud would go away...

We're predicted to get some very nice seeing in Bris from Wednesday onwards. At least for 2-3 days...

But as usual, it's clouded out when Brisbane finally gets a run of good seeing