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Refiguring a Dynamax 8" Schmidt Corrector

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#651 Mitrovarr

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Posted 16 January 2018 - 04:31 PM


I would agree with that if the Dynamax was merely a mediocre telescope, but it's not. It's awful. Once I got better telescopes, the DX8 went into the basement to live forever, never emerging except for the occasional fruitless attempt to fix the bloody thing.

In the world of commercial telescopes...perfection is sometimes hard to achieve. I'm sure there are those who probably have said the same about a C-8 too....

Klitwo

Yes, but now you are hearing it from someone who likes standard commercial optics just fine. Most Dynamaxes make the average C8 look like it was hand figured by master opticians.

#652 SteveNH

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Posted 16 January 2018 - 04:36 PM

"[... After seeing how long and arduous of a procedure it is, I don't have a lot if desire to fix mine ... ]"

 

To me, this thread is more about the way to work out a streamlined/ efficient procedure to improve a seemingly optically hopeless (but otherwise noteworthy) classic, than being a step-by-step instructional view at fixing a bad corrector plate. The fact that Dave is willing to share in his posts his tedious increments of logic and procedure to get to the best solution is truly appreciated and extremely interesting to me. The new and improved corrector plate that hopefully comes out of all this is just a happy by-product of this research, from which all who choose to can benefit. The rare privilege to witness Dave's day by day experiences is one of the reasons I keep coming back to Cloudy Nights.

 

Steve


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#653 davidc135

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Posted 16 January 2018 - 04:50 PM

I took a decent looking moon shot through my Dynamax, too.

I don't think it really reveals much. I think the optical standard necessary to take a decent looking low power moon pic is pretty low.

The smallest craterlets in the photos seemed to be about 3km diameter (?) across so a bit better than a 'decent low powered moon pic'. Very likely a DPAC test would reveal flaws.  At any rate it's another interesting metric: What's the best image that can be produced with 1 wave, 1/2, 1/4 or 1/10 wave optics even with Photoshop? What errors can you get away with, if any?

 

David


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#654 Mitrovarr

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Posted 16 January 2018 - 05:52 PM

I'm curious - have you ever used a Dynamax? They don't deserve to get compared to vintage C8s from the 70s. Dynamaxes aren't imperfect, they're bad.
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#655 Geo31

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Posted 16 January 2018 - 05:59 PM

Sweet Jesus...

 

Folks, come on....  We've already had one thread Dave started about this process go bad because of pointless and needless bickering.  I'm hardly the thread police, but go find that thread and share your opinions there.  Please.

 

This thread is IMHO truly a rare treat.  We have optical guru willing to share not only his accomplishments, but the process (including thoughts) he's going through to get there.  Not too many posts ago he mentioned just waiting until the end to share the results, but I (for one) implored him to keep sharing the process because that, in and of itself, is valuable.

 

Let's not screw this thread up too.  Please.


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#656 Mitrovarr

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Posted 16 January 2018 - 06:15 PM

Ok, ok. Sorry, a Dynamax was my first serious telescope and I was stuck with it for nearly 10 years. I'm still bitter about that. I'll try not to dump it into this thread, though.

I do really appreciate his hard work here. It's absolutely fascinating to read about what is wrong with it and how it can be fixed. I'm not likely to try it myself, for a number of reasons (no space, no equipment, no ATM skill, etc.) but I am still really interested.
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