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Sorry Rob but in your latest foucault and ronchi pics I'm seeing a turned down edge, not turned up. I guess the important thing is that the strokes you're using are improving the problem.

Dave

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Really..looks more like parabolical sweep to me.

I'll test again tomorrow. I don't see how my machine can even produce a turned down edge...there is no flexin of the tool.

Rob

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www.goldmtobservingcenter.com
A great place for amateur astronomers, and ATM's to come and enjoy their hobby.

http://tech.groups.yahoo.com/group/HomemadeRefractorTelescopes/ My homemade refractor group.

www.vimeo.com/6014031

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So Im guessing that my mirror is approaching completion??,
but (and I might get in truoble for asking) how many have you left to do..?.
I know its none of my business, but since your using mine at the protoype I thought it might be nice ot know how many rwiederrich mirror sibling it'll have..

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I'm hoping within the next few weeks I'll have it done.....seeing the winter months are coming and I have other stuff to attend to.

I hope there are plenty of family members...

Rob(It's just a hobby)

--------------------
www.goldmtobservingcenter.com
A great place for amateur astronomers, and ATM's to come and enjoy their hobby.

http://tech.groups.yahoo.com/group/HomemadeRefractorTelescopes/ My homemade refractor group.

www.vimeo.com/6014031

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Rob(It's just a hobby)

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hmmmmmm tryin to convince yourself.....

no matter how many you do, I wish you success, who knows this could be that elusive job everyone looks for, one you actually love ot do.

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12 inch Truss Reflector "John"
102mm Celestron C102HD " Carl "
Tasco 7TE5 60mm Classic
Tasco 9TE5 60mm Classic
Celestron Ultima 2000 SCT "Wilma"
Celestron Comet catcher(orange tube)
1960 Edscorp Space Conquerer 6inch f/8
10x50 Bushnell Binoculars.


60mm Telescope Club

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Really..looks more like parabolical sweep to me.

I'll test again tomorrow. I don't see how my machine can even produce a turned down edge...there is no flexin of the tool.

Rob

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Really..looks more like parabolical sweep to me.

I'll test again tomorrow. I don't see how my machine can even produce a turned down edge...there is no flexin of the tool.

Rob

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Ok it might be better described as a long outer zone than a TDE but I certainly don't see TUE.

I've been somewhat baffled with your images though. You said on 10/09/09 10.44pm that you can make the knife edge come in from the left or right but that it is coming from the right. In that case your drawing of 10.38pm is an oblate spheroid. On 10/10/09 6.03pm you posted an image that you said is what you drew but the shadows are reversed indicating a deep hyperboloid (unless you changed the knife direction). Then the monitor pic at 07.38pm is reversed again like the drawing. On the 10/14/09 12.38pm we have changed again??? In all foucault pics I don't see the diffraction ring completey around the edge.
The ronchi pics are without confusion though and show (to me at least) undercorrected inner zones and strongly corrected outer zone.

Dave

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Dave you are correct. Some images show the KE coming in from the left and right. I failed to differentiate them.

I built my tester to have that feature. Were as a typical tester uses an X.Y table arrangment....I build in my tester the ability to swing the Ke into the light cone from left or right independant of the Y axis. It permits me to see the zones from several aspects and to evalute the different shadow paterns.

You are also correct in suggesting that the mirror currently has an undercorrected central zone and a very corrected outer zone....hence my current work to push the center down..creating the necessary parabaloid.

All the images I have presented thus far are for the readers edification..not as an accurate representation of my technique or process.

From a file of many images I sellect some that show the greates change and shadow differentiation.

I do appreciate your input and evaluation...and can only learn from them.

Rob(greatful)

--------------------
www.goldmtobservingcenter.com
A great place for amateur astronomers, and ATM's to come and enjoy their hobby.

http://tech.groups.yahoo.com/group/HomemadeRefractorTelescopes/ My homemade refractor group.

www.vimeo.com/6014031

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Rob(It's just a hobby)

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hmmmmmm tryin to convince yourself.....

no matter how many you do, I wish you success, who knows this could be that elusive job everyone looks for, one you actually love ot do.

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No..it's just a hobby....

But I am working and planning on it becoming a retirement job...if we're all still here.

Rob

--------------------
www.goldmtobservingcenter.com
A great place for amateur astronomers, and ATM's to come and enjoy their hobby.

http://tech.groups.yahoo.com/group/HomemadeRefractorTelescopes/ My homemade refractor group.

www.vimeo.com/6014031

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and maybe one small spot slightly below center out of focus????

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Nope..that is a felt backing on the mirror stand that presses on the back of the mirror keeping it from coming in cantact with the metal permitting adequate air flow around the mirror.. It's just a spacer you can kinda see though the mirror.

Any thoughts?
Any feedback?

Rob

--------------------
www.goldmtobservingcenter.com
A great place for amateur astronomers, and ATM's to come and enjoy their hobby.

http://tech.groups.yahoo.com/group/HomemadeRefractorTelescopes/ My homemade refractor group.

www.vimeo.com/6014031

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Any thoughts?
Any feedback?

Rob

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Any thoughts?
Any feedback?

Rob

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cant wait to hug my mirror...lol

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Now there's a thought.....

Man..I'm fighting this roughness issue.

And that dang edge.

Here is an image of a closeup of the rough surface.....
It just needs more polishing.......

Rob

--------------------
www.goldmtobservingcenter.com
A great place for amateur astronomers, and ATM's to come and enjoy their hobby.

http://tech.groups.yahoo.com/group/HomemadeRefractorTelescopes/ My homemade refractor group.

www.vimeo.com/6014031

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