Quote:
Originally Posted by Joshua Bunn
Thanks Mike,
I have had a look at the file, and will be in touch with you soon to discuss your specific requirements.
Cheers, Joshua
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I'd like to be kept in the loop if possible.
From what I understand the focuser attached to the mirror introduces strain/image shift. By removing the focuser and fitting a dedicated mounting point the mirror can't get the distortion.
I hang a heavy Nikon D810 full frame camera off a heavy home design 2 inch aluminium adapter which weighs (wait, I'll check)........
OK, my adapter sans eyepiece (12mm Vixen Lanthanum) weighs around....
CRAP, I forgot, here goes again....
https://i.postimg.cc/gcZmK64K/IMG-1797-4146x3110.jpg
https://i.postimg.cc/151P75j1/IMG-1798-4146x3110.jpg
https://i.postimg.cc/SRC4QwjP/IMG-1799-4146x3110.jpg
Sorry!
The adapter sans eyepiece weighs around 440 grams. It's my design I had an engineer friend machine, 2" extension heavy build which accepts a 1.25" eyepiece and works reasonably well for eyepiece projection and straight photography. I could have designed it to be thinner and lighter but that would have taken longer and cost more to machine. Sadly I'm an old school heavy welding type person (former forklift technician, everything has to carry a big load), if the bridge has to hold the weight of 2 cars it's going to also support the row of Sherman tanks following.
Not good for astronomy.
The camera body alone weighs 980 grams from what I found online, add in the extension rings (I think with my adapter I still had to use the 2" extension ring to achieve focus with an eyepiece), it all adds up to near enough to 1500 grams hanging a reasonable distance from the mirror where the focuser attachment ring attaches.
In mention of CNC stuff, the fellow on the astronomy forum who does the custom CNC units and suggests sending the rear plate to the US offered me full cnc specs to try and make one myself. That would be so easy if I had a cnc machine, half a brain and an idea as to how to use it.
Funny mention, he even offered to convert the offsets to metric believing no one in Australia would understand imperial. I did until I did my 4th form leaving certificate at high school in metric after being taught imperial for so many years......
Following is a stitch of 3 images (vertical sectioning) through the 12mm eyepiece through my extension set up. Focus was not great but my eye sight isn't the best. The issue with focus could be the very strain on the primary mirror I'm talking about
:
https://i.postimg.cc/sg2YkyMw/Crater...-9825x3663.jpg
Here's the thread in Cloudy nights which I hope is allowed,soory if it's not:
https://www.cloudynights.com/topic/8...ation-adapter/