WTS : 203mm f/4 newtonian OTA + Rings (Sold out!)
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orly_andico
- Posts: 1616
- Joined: Sun Aug 09, 2009 11:14 pm
- Location: Braddell Heights
- Contact:
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dragoncai2008
- Posts: 24
- Joined: Thu May 06, 2010 2:34 pm
- Location: Choa Chu Kang
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dragoncai2008
- Posts: 24
- Joined: Thu May 06, 2010 2:34 pm
- Location: Choa Chu Kang
@croys
I managed to get contact with the mirror master,Mr.Sue Lu Dingh, which is actually his nick name in amateur world, but it's much more well-known than his true name. He has his own workshop, and now is planning to expand it.
Two weeks ago, I talked to him by IDD and advised him to try to push his mirrors to international users. he agreed to let a try, thus why I put a free advertisement here on behalf of him. You want to put an order? Do you speak mandarin? I have his mobile number, but he does not speak any english.
So far he can make up to 600mm mirror, but at that size, he told me, the accuracy can only be 1/10 wave. 254mm size got f4, f5, f6. if you wanna 300mm I think the focal ratio can be similar. He told me he's going to make 254 RC mirror later this year, but that one S$1000 around.
My mirror(main/flat)+coating will be ready in this July or August. and then He will UPS/FedEx to my friend in ZhuHai, a city adjacent to Macau. then I will go to fetch when I go to Macau or HK. or alternatively ask my buddy to UPS/FedEx to Singapore, but that may cost some $$.
attached is two test photos of his mirror.
I managed to get contact with the mirror master,Mr.Sue Lu Dingh, which is actually his nick name in amateur world, but it's much more well-known than his true name. He has his own workshop, and now is planning to expand it.
Two weeks ago, I talked to him by IDD and advised him to try to push his mirrors to international users. he agreed to let a try, thus why I put a free advertisement here on behalf of him. You want to put an order? Do you speak mandarin? I have his mobile number, but he does not speak any english.
So far he can make up to 600mm mirror, but at that size, he told me, the accuracy can only be 1/10 wave. 254mm size got f4, f5, f6. if you wanna 300mm I think the focal ratio can be similar. He told me he's going to make 254 RC mirror later this year, but that one S$1000 around.
My mirror(main/flat)+coating will be ready in this July or August. and then He will UPS/FedEx to my friend in ZhuHai, a city adjacent to Macau. then I will go to fetch when I go to Macau or HK. or alternatively ask my buddy to UPS/FedEx to Singapore, but that may cost some $$.
attached is two test photos of his mirror.
- Attachments
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- 150mm mirror
- 150mmNewtonianTube.jpg (19.88 KiB) Viewed 2812 times
I Like DIY.
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dragoncai2008
- Posts: 24
- Joined: Thu May 06, 2010 2:34 pm
- Location: Choa Chu Kang
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orly_andico
- Posts: 1616
- Joined: Sun Aug 09, 2009 11:14 pm
- Location: Braddell Heights
- Contact:
@dragoncai2008: in your last few posts, you have elaborated with some details, which is good, as it seems clearer to us now.
It is certainly a far cry from your original post, where an unknown guy making his 1st post on this forum states "I accept international order...main mirror, accuracy: 1/10-1/20...." then "10 inch primary & secondary mirrors for S$330...." At that point it could seem like a potential new vendor with a possible scam....
I was bemused to note that those who had replied to your post so far are people who have built scopes, going to build one, own premium scopes, or all of the above. Certainly not likely to fit in the 'gullible' or 'ignorant' category.
In fact I was on the lookout for a primary mirror in the last few days, so it would have been useful if you had provided more information and background reference links upfront. Anyway I have already
concluded the deal elsewhere, so I will have to skip on your good-value deal for now. I have seen and use GSO and Synta scopes with good optics, and we await to see consistently exceptional optics being produced.
Do update us on the outcome and results of your 10" scope project. If you need any help, or would like to test it with some 'basic and limited' tools, let me know. Perhaps we can also arrange for side-by-comparison observation with a premium scope as a benchmark, that would be interesting to see.
To me, it is not the issue which test is better or more accurate. Even if a test is more sophisticated and advance that it can differentiate between, say, 1/20 and 1/40 wave acuracy, or detect and distinguish minute aberrations, it is noteworthy that most people may not be able to discern between a scope, say, with 1/8 p-v wavefront from one with a 1/20 rating.
So what matters at the end of the day is the scope's optical performance as observed through the eyepiece, and whether you are happy with the scope you are using, and then to put it to good use.
It is certainly a far cry from your original post, where an unknown guy making his 1st post on this forum states "I accept international order...main mirror, accuracy: 1/10-1/20...." then "10 inch primary & secondary mirrors for S$330...." At that point it could seem like a potential new vendor with a possible scam....
I was bemused to note that those who had replied to your post so far are people who have built scopes, going to build one, own premium scopes, or all of the above. Certainly not likely to fit in the 'gullible' or 'ignorant' category.
In fact I was on the lookout for a primary mirror in the last few days, so it would have been useful if you had provided more information and background reference links upfront. Anyway I have already
concluded the deal elsewhere, so I will have to skip on your good-value deal for now. I have seen and use GSO and Synta scopes with good optics, and we await to see consistently exceptional optics being produced.
Do update us on the outcome and results of your 10" scope project. If you need any help, or would like to test it with some 'basic and limited' tools, let me know. Perhaps we can also arrange for side-by-comparison observation with a premium scope as a benchmark, that would be interesting to see.
To me, it is not the issue which test is better or more accurate. Even if a test is more sophisticated and advance that it can differentiate between, say, 1/20 and 1/40 wave acuracy, or detect and distinguish minute aberrations, it is noteworthy that most people may not be able to discern between a scope, say, with 1/8 p-v wavefront from one with a 1/20 rating.
So what matters at the end of the day is the scope's optical performance as observed through the eyepiece, and whether you are happy with the scope you are using, and then to put it to good use.
Richard Low
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dragoncai2008
- Posts: 24
- Joined: Thu May 06, 2010 2:34 pm
- Location: Choa Chu Kang
thank you guys for your comments on my post. I am surely not a vendor. I am just like you, an astronomical amateur. I put 254mm mirror sale info just in favor of the Chinese mirror master Mr. Sue. it is a volunteer help, I earn no cent at all.
I have ordered my 254/f5 reflector mirror from him, but preparing all the necessary parts to form a telescope is a difficult job for me, particularly the 10" tube, I may consider to use truss frame.
I guess it may take 6 months to finish. I will keep you all updated with my progress and once I finished the OTA tube, will put on photos and also glad to meet you somewhere to check the optical performance of this DIY newtonian telescope.
I have ordered my 254/f5 reflector mirror from him, but preparing all the necessary parts to form a telescope is a difficult job for me, particularly the 10" tube, I may consider to use truss frame.
I guess it may take 6 months to finish. I will keep you all updated with my progress and once I finished the OTA tube, will put on photos and also glad to meet you somewhere to check the optical performance of this DIY newtonian telescope.
I Like DIY.