Where to buy 24" + Mirrors in Australia? - Page 2

Satchmo · #21 22-12-2008, 05:28 PM

Quote:

Originally Posted by Davekyn

I can get a new 16" GSO mirror for $999.00 therefore was hoping a 24" may be availabe for 3-4000.
<SNIP>
No doubt ,I'll cop the premium jargon today when I ring Sydney.

Dave, The current cost of importing a precision borosilicate fine annealed 24" mirror _blank_ and getting it aluminised ( without considering the cost of having it ground and polished ) is running at around AUD $6500. To import a 24"-25" finished mirror _to your front door_ from a reputable maker like OMI or Galaxy will currently set you back $15-$17,000 AUD.

If you can actually import a commercial anneal plate glass GSO 16" mirror currently to your front door for less than $1750 please let me know, I will buy one for my 13 yr old nephew

JethroB76 (Jeff) · #22 22-12-2008, 05:29 PM

Agree with Starkler, thats an odd typo

I would be surprised if you find a 24" mirror less than $8000

*edit seems I was being conservative haha, ok maybe $8000 four months ago

Ian Robinson · #23 22-12-2008, 06:53 PM

Quote:

Originally Posted by Satchmo

Guess it was this same attitude to local industry that closed your local Newcastle steelworks

No - it was poor management by the board of BHP and then by the same people who became the board of Onesteel.
And the Howard government did absolutely nothing to encourage Onesteel to keep the steelworks going (Newcastle's a labour seat) , nor did they do anything to help steelworkers retrain. Their silence at the time was deafening.

I can't comment on the quality of local mirror makers - never bought a mirror locally.

With the size of the Australian marketplace , the locals are never likely to have enough demand to compete with the big mirror makers overseas who have in the game for decades .

Starkler (Geoff) · #24 22-12-2008, 07:04 PM

Quote:

Originally Posted by Ian Robinson

With the size of the Australian marketplace , the locals are never likely to have enough demand to compete with the big mirror makers overseas, and most of them have in the game for decades .

Ian when I went shopping for a mirror, the local producer won my business.

I asked price and availability for an OMI-Torus 15" f4.8 mirror, and they wouldnt make one for me, even thought its a catalogue item on their website. I could have got a 15" f4.5 for $3750 delivered but thats not what I wanted.

Seems they were too geared up into mass producing for Obsession telescopes and didn't want to reset a machine just for me.

I got the local product made to MY specifications and over $500 cheaper even after paying a surcharge for a custom focal length. The reputation of the mirror maker suggests it will be equal or better than the omi-torus.

Have you ever shopped for a mirror Ian?

Ian Robinson · #25 22-12-2008, 07:49 PM

Quote:

Originally Posted by Starkler

Ian when I went shopping for a mirror, the local producer won my business.

I asked price and availability for an OMI-Torus 15" f4.8 mirror, and they wouldnt make one for me, even thought its a catalogue item on their website. I could have got a 15" f4.5 for $3750 delivered but thats not what I wanted.

Seems they were too geared up into mass producing for Obsession telescopes and didn't want to reset a machine just for me.

I got the local product made to MY specifications and over $500 cheaper even after paying a surcharge for a custom focal length. The reputation of the mirror maker suggests it will be equal or better than the omi-torus.

Have you ever shopped for a mirror Ian?

Yes I have, I bought several over the years , mostly for other people, and I've never had a problem getting one made to spec. I've dealt with mostly with Orion UK , Nova , NPGW and Parks.
The choice of wavefront tolerances , thicknesses, substrates and coatings is a big plus too.
Never bought one from Torus though I bought other stuff from them over the years on behalf of others.

Davekyn (David) · #26 22-12-2008, 08:06 PM

No problem...editing done...perhaps you can edit your response now as that's the only mention of it now.
Yes I understand & thought that the larger a mirror gets, the harder it would be to keep the quality. 0h well...I take it 16" inch must be it for now. That,a quite a price for the extra quality. Could you explain what the difference in quality is? Do they clean up better & can you clean them more often? Is there more brightness & contrast than what extra baffling can provide? Ofcourse I have no idea, however I would apreciate if someone could posibly explain the actuall difference between the two.

Don't get me wrong. I can apreciate those minor differences...however, if the difference is good enough, then surely someone could describe it?

Davekyn (David) · #27 22-12-2008, 08:14 PM

Wow!...ok I got the messege guys..."page just refreshed" if I can find that link on 999$ GSO mirror, I'll post it. Turns out I can't find it-go figure.

Mmmmmm...guess I,ok have to work on a 16" version then. May I ask can anyone comment on the extra 4" a 16" has over a 12". I really had no idea. My apollogies...I guess I just need to really mull over the "premium" aspect.

Paddy (Patrick) · #28 22-12-2008, 10:03 PM

Quote:

Originally Posted by Davekyn

May I ask can anyone comment on the extra 4" a 16" has over a 12". I really had no idea. My apollogies...I guess I just need to really mull over the "premium" aspect.

Well, I have to say that I have found the upgrade from 12" to 16" to be well worth while. Nearly double the light collected and better resolution. This is also going from a GSO 12" primary to a premium 16". I still reckon the best option is to have a look through and at a few. The other option for collecting more light would be a binocular telescope, but then you'd have to double your eyepiece collection. There would be quite a few people on this forum who could tell you more - I still haven't looked through a binewt myself yet.

Satchmo · #29 22-12-2008, 10:20 PM

Quote:

Originally Posted by Ian Robinson

Yes I have, I bought several over the years , mostly for other people, and I've never had a problem getting one made to spec. I've dealt with mostly with Orion UK , Nova , NPGW and Parks.

So basically you are happy to recommend a heap of US companies ( Nova, Swayze, Galaxy) you have never had dealings with over local production you have never had dealings with. Given the current US/AUD exchange rates , what can be said? : clearly treat advice from 'armchair experts' on forums with the caution it deserves.

Ian Robinson · #30 22-12-2008, 10:55 PM

Quote:

Originally Posted by Satchmo

So basically you are happy to recommend a heap of US companies ( Nova, Swayze, Galaxy) you have never had dealings with over local production you have never had dealings with. Given the current US/AUD exchange rates , what can be said? : clearly treat advice from 'armchair experts' on forums with the caution it deserves.

Well, I also recommended someone from the UK and
1) I never claimed to be an expert , umm I take you regard yourself as an expert ..
2) I've had dealings with these companies and they've done excellent work
3) market here in Australia small so every mirror above say 12" will be a one off therefore more expensive (economics), I've had no cause to deal with the local chap
4) I'm not twisting anyone's arm and forcing them to spend their money elsewhere (there is no compelling reason to buy locally except the exchange rate is currently unfavourable), but anyone looking to buy an optic will be well advised to talk to several suppliers before committing not just the locals.

monoxide · #31 22-12-2008, 11:16 PM

i'd call Mark an expert, atleast regarding the topic of this thread.

anyway back on topic, i'd make a truss scope with what you have there to start with, i wouldnt want the first scope i built to be one you need a stepladder to look through

i'm still in the planning stages of converting my 12" dob to a truss dob.
theres a lot of people on here that have done it all before and can offer excellent advice. also if you start small you can see where the problem areas might be when you go bigger.

Davekyn (David) · #32 22-12-2008, 11:22 PM

Sounds like good advice Rob. Now that I am much more informed on the situation, I do believe I will settle for buying the recomended book & even the DVD Erick mentioned. From there I will experiment with my current Dob. The Bino dob setup actually makes sense now...I use to wonder why people bothered, but clearly that too could be an alternative with chineese optics.

Whatever the score...thankyou very much.

JethroB76 (Jeff) · #33 23-12-2008, 12:27 AM

Quote:

Originally Posted by monoxide

i'd call Mark an expert, atleast regarding the topic of this thread.

That 'local chap' eh?

Starkler (Geoff) · #34 23-12-2008, 02:17 AM

Quote:

Originally Posted by Davekyn

No problem...editing done...perhaps you can edit your response now as that's the only mention of it now.

Done, and thanks.

Satchmo · #35 23-12-2008, 09:44 AM

Quote:

Originally Posted by Ian Robinson

3) market here in Australia small so every mirror above say 12" will be a one off therefore more expensive (economics).

You've clearly done absolutely _zero_ research on that one...

Quote:

Originally Posted by Ian Robinson

(there is no compelling reason to buy locally except the exchange rate is currently unfavourable)

Ian Robinson · #36 23-12-2008, 10:29 AM

Since you reckon I am wrong. So how big do you think it is - volumewize ?

Satchmo · #37 23-12-2008, 11:16 AM

Quote:

Originally Posted by Ian Robinson

So how big do you think it is - volumewize ?

The Universe ?

bmitchell82 (Brendan) · #38 23-12-2008, 12:12 PM

Satchmo, stop playing with Ian

and by the way can you look at my post in ATM DIY about multi mirror optics and comment.?

skies2clear · #39 23-12-2008, 04:15 PM

Oh dear, if only the truth was apparent!

Funny and sad!

tnott · #40 23-12-2008, 05:25 PM

Davkyn,

The only reason the GSO mirrors are substantially cheaper is that they are mass produced in China. No such thing exists for mirrors above this size. They are all custom made products - which is probably just as well as the difficulty in making them goes up almost exponentiallythe bigger they get.

Some GSO optics turn out pretty OK and others are mediocre to lousy. The risk you take when you buy the cheaper stuff is that you may have to get it refigured anyway.

I think the amount the good US and Aussie mirror makers charge is a bargain, given the amount of work involved in making them. You should see how much my plumber charges per hour.