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View Full Version here: : Getting a primary mirror refigured in Australia.


GUS.K
09-02-2025, 09:20 AM
I'm after someone to refigure a 16 inch f4.5 mirror to maybe an f3.5 to f4. Is there anyone in australia that still offers this service. I'm not interested in sending overseas or purchasing a new mirror, I would like to get it done locally if possible.
Thanks.

glend
09-02-2025, 09:09 PM
There used to be a guy in Tuncurry NSW that offered mirror services. I can't remember his name. I will do some searching and get back to you if I can find him.

Matthieu
09-02-2025, 10:41 PM
Lookup Wayne Sainty from palmwayoptical.com. I found his details here a couple of years ago, got a quote also for a 16" f/4.5 but thought I'd get the current coating to last for as long as it can.

Good reminder for me that there is visible corrosion so I should get it done.

GUS.K
10-02-2025, 05:48 AM
Thanks guys, I'm not looking for a recoat but a refigure of the mirror from an f4.5 to something faster. Wayne doesn't refigure mirrors, he only does optical coatings.

NCRAW
10-02-2025, 11:28 AM
Speak to Stefan Buda here on IIC see if he can help or suggest something.

Satchmo
10-02-2025, 11:49 AM
That's technically a complete regrind . The term refigure usually applies to a touch up on the polished mirror taking it say from 1/4 wave to 1/12 wave etc. In this case you are just supplying a blank as a basis for making a completely new mirror .


Probably not worth all the expense for an F4 . Aluminising and stripping a 16"would be around $600- $700 these days alone .



Just did a sanity check on a Zambuto 16"F4 landed - about $13500 . Ouch !


If its for imaging have you considered a Nexus X 0.75 coma corrector , which makes your F4.5 an F3.3 ?

GUS.K
10-02-2025, 12:42 PM
Thanks all. Mark, are you still doing mirrors?

Satchmo
12-02-2025, 01:11 PM
Hi Ivan , I wouldn't be tinkering with a known high quality finished mirror ;) . I use a 16"F4.5 myself for personal viewing .


With the range of focal lengths in eyepieces these days I don't think there is so much to gain between different focal ratios bar the smaller secondary on slower scopes .


As we get older the eye probably doesn't open more than 5mm so that suits an F4.5 with normal eyepieces in the 25mm to 22mm range nicely . You can still get away with a coma corrector at F4.5 but at F3.5 its necessary and you end up at F4 anyway with the amplification factor visually .

GUS.K
16-02-2025, 02:52 PM
Thanks Mark. The mirror was a fine working mirror , which was recently damaged. For personal reasons I would like to get it refigured if possible, or reground if refiguring is not viable due to damage.