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Should i refigure?

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#1 CHASLX200

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Posted 11 February 2019 - 08:53 PM

Got a nice used Meade 8" F/6 826 from around 1980.  I would say the mirror is very good and seems to handle a 3mm Delite on the moon pretty darn good, but seems to lack that extra pop i have had from my Zambuto's and a RV6 i have now.   I think the mirror could made better.  Now i gotta wonder who should do the work?  I always wanted a Mike Lockwood mirror since i have heard nothing but great things.  We all know Zambuto does great work.  I know there other optics makers that also do great work.

 

Be nice to have the mirror tested and go from there.  What would you guys do?  You all know i am picky and have the steady seeing that would alllow a super mirror to do it's stuff.  This is a light weight OTA and my days of big scopes are over.


Edited by CHASLX200, 11 February 2019 - 08:53 PM.

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#2 Asbytec

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Posted 11 February 2019 - 09:10 PM

If you feel the need, can afford it, and the anneal can take the strain...go for it. I guess it depends on whether the extra (unknown) amount of "pop" is worth it to you. If you're okay with the views in the 3mm Delite, so be it. It's not a terrible mirror, apparently. If you want the best and be sure it is, however, have it re-figured by any one of the best in the business. At the best price you can get (help drive the prices down for the rest of us lol.gif ). 


Edited by Asbytec, 11 February 2019 - 09:14 PM.


#3 photoracer18

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Posted 11 February 2019 - 09:59 PM

I got 2 mirrors I am contemplating. But in either case I will send them out for testing first. If they comeback 1/4 wave or better then likely I will leave them alone (well maybe not the Dick Brandt mirror). But the other is a plain-Jane Meade 16" from a Starfinder Dob and no telling who figured it first.

#4 Richard O'Neill

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Posted 11 February 2019 - 11:11 PM

Have Optical Ed test it for you. https://opticaleds.c...r-refiguring-2/



#5 Pinbout

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Posted 12 February 2019 - 01:26 AM

Got a nice used Meade 8" F/6 826 from around 1980.  I would say the mirror is very good and seems to handle a 3mm Delite on the moon pretty darn good, but seems to lack that extra pop i have had from my Zambuto's and a RV6 i have now.   I think the mirror could made better.  Now i gotta wonder who should do the work?  I always wanted a Mike Lockwood mirror since i have heard nothing but great things.  We all know Zambuto does great work.  I know there other optics makers that also do great work.

 

Be nice to have the mirror tested and go from there.  What would you guys do?  You all know i am picky and have the steady seeing that would alllow a super mirror to do it's stuff.  This is a light weight OTA and my days of big scopes are over.

get a new 2ndry 1st


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#6 Pinbout

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Posted 12 February 2019 - 01:28 AM

 

3mm Delite on the moon pretty darn good,

that's a .5mm exit pupil, you don't want any smaller. 

 

2mm exit pupil suppose to present best image

 

below 1mm exit pupil stuff starts to dim.



#7 CHASLX200

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Posted 12 February 2019 - 06:10 AM

get a new 2ndry 1st

From who?  And will it fit my 2ndary holder?  This is a curved Novak spider and holder.



#8 CHASLX200

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Posted 12 February 2019 - 06:13 AM

that's a .5mm exit pupil, you don't want any smaller. 

 

2mm exit pupil suppose to present best image

 

below 1mm exit pupil stuff starts to dim.

I have no problems using these crazy powers.  I really need a 2mm eyepiece.  The moon takes crazy powers the best since it is bright. I have had no problem using 400 to 500x  on Jupiter with many 8" scopes.  But after 400x Jupiter starts to dim as does Saturn. Venus and Mars when close can take higher powers since they are brighter.


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#9 Starman47

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Posted 12 February 2019 - 07:04 AM

One of the best mirror makes out there, even if not as widely recognized as Zambuto, is Gordon Waite (with Waite Research). He tested my 12” GSO (no charge other than shipping). He told me it was a great exapmple for a GSO. And he said it did not need refiguring. Just a FYI, it tested out at 1/10 wavefront. He also added that if I wanted better views that I should think about a new secondary. He advised a secondary from Antares. 

 

I purchase the secondary from Antares and a new spider/secondary holder from Astrosystems. The new telescope curse also applies to components bangbang.gif bangbang.gif  So I have yet to get out under the stars.


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#10 Pinbout

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Posted 12 February 2019 - 08:58 AM

 

He advised a secondary from Antares.

i'll second that secondary

 

 

He tested my 12” GSO (no charge other than shipping). He told me it was a great exapmple for a GSO.

I recently tested someone's 12" and it tested very well also.


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#11 CHASLX200

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Posted 12 February 2019 - 06:42 PM

i'll second that secondary

 

I recently tested someone's 12" and it tested very well also.

I know the one in my 10" F/6 Cave is very good and it is also a Novak holder and spider so it should plug and play in the 8" Meade.


Edited by CHASLX200, 12 February 2019 - 06:42 PM.


#12 CHASLX200

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Posted 14 February 2019 - 06:31 PM

Guess i will go with a new blank and just sell the Meade mirror i have. It would make anyone happy.



#13 Asbytec

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Posted 14 February 2019 - 10:24 PM

You mean, anyone else happy? :)
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#14 Pinbout

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Posted 14 February 2019 - 11:02 PM

Guess i will go with a new blank and just sell the Meade mirror i have. It would make anyone happy.

So a new blank will make you happier than a stock finished mirror that does well up to .5mm exit pupil?  lol.gif

 

maybe a larger dia.  longer focal length... more detail at higher mag


Edited by Pinbout, 14 February 2019 - 11:02 PM.


#15 CHASLX200

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Posted 15 February 2019 - 06:15 AM

So a new blank will make you happier than a stock finished mirror that does well up to .5mm exit pupil?  lol.gif

 

maybe a larger dia.  longer focal length... more detail at higher mag

I have that already. Seems no one wants to refigure what i have.  I have a 10" Cave, but the OTA is getting too heavy so a 8" is something i would use more.  I guess i could make the 10" Cave OTA lighter by removing the heavy rotating rings and thick Cervit mirror.  Going with clamp rings and a thinner blank could shave a good 15lbs off the OTA.


Edited by CHASLX200, 15 February 2019 - 06:22 AM.


#16 CHASLX200

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Posted 11 April 2019 - 05:34 AM

Had the 826 Meade out this AM on Jupiter.  With a 3mm Delite the image looked pretty darn good.  Plenty of detail, backed down to a 5mm Radian and that seemed to give the best view with plenty of detail.  I think the mirror is good enough as is. Spent lots of time getting the 2 dary collimated so everything is as good as it can get.  Have a much better mount coming so all will be well.  These old school Newts are hard to beat.


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