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Depressed-accident with my new mirror

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#26 whirlpoolm51

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Posted 19 November 2012 - 10:24 PM

Feel your pain!!! When i had my orion xt12i awhile ago i was collimating and getting everything ready before i took it out for a good nights observing , i went into my kitchen to make a cup of coffee and all of a sudden........i hear a pings of somthing smacking of an aluminum tube and a loud smack!!! To my dismay , my little brother decided to see how fast a hot wheels car could go down the tube of my scope!!!!!!!! Lucky for that little bugger i love him or i would be an only child hahahaha 2 little chips in my mirror that had my head spinning for days!!!

This hobby will drivce you crazy if you fall in love with it as much as we do hahaha

#27 killdabuddha

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Posted 20 November 2012 - 12:32 AM

We were draggin our scope sled-style across uneven ground, then we weren't, cus it tipped over and crashed before we could catch it. The mirrors spilled out onto the square tubes and my first thought was, "I shoulda used round." And yeah, the sound is even worse. Got 'em inside, blew them off, and looked really hard for the damage. It showed up days later as a little abraded smear at the edge where the coating left. Glad we got that over with.

#28 RussD

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Posted 21 November 2012 - 10:49 AM

I feel your pain. I once dropped a 2" adapter on my full thickness 10" mirror, it bounced (tink) and bounced (tink,tink) and bounced (tink,tink,tink,tink...)then rolled around.

There were several scratches in the coating and other minor marks. Other than the coating scratches there was no real damage to the mirror.

At one of our club star parties once a friend was looking through his scope and suddenly though it had clouded over because the stars faded away. He looked at the sky only to see it was clear. He finally looked down at his mirror to see a stray cat had climbed into his rocker box for a nap on the nice smooth mirror!

Russ

#29 GeneT

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Posted 21 November 2012 - 10:54 AM

You need to get it out for a few more viewing sessions. What matters is how the views are affected. Put Jupiter under a little magnification and move the image around various parts of the field of view to see if there is a sudden change in image quality.

#30 Asbytec

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Posted 21 November 2012 - 11:48 AM

You know, it sucks. We care so much for our instruments, and we should. We've all dinged them and cringed mightily.

Truth is, a little ding will not likely have the proper surface correction to send an errant ray or two anywhere near focus. So, you will likely not even notice any scatter, or turned edge, or anything like that. I seriously doubt such an impact changed its figure to below diffraction limited. That would take a truly freak accident. I am pretty sure your glass didn't shatter like a car window.

Paint it over, feel good...smile. Be happy, well, when you find closure - probably during your next viewing session. Soon enough, someone else will have an accident, and you will have a story to tell them. :)

#31 JasonBurry

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Posted 21 November 2012 - 12:21 PM

Another one here who's dropped an object on his primary mirror, in my case my 12.5mm plossl fell from my shirt pocket as I bent over the scope.

Mine suffered a 2X1mm ding in the coating, and no detectable effects at the eyepiece. Live and learn.

J

#32 csrlice12

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Posted 21 November 2012 - 02:34 PM

That's the sky goddess's way of telling you you need a bigger scope..... :waytogo:

#33 Mike B

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Posted 21 November 2012 - 04:43 PM

.... or else just messin' with our heads...
:ohmy:

#34 ed_turco

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Posted 21 November 2012 - 05:13 PM

I pulled this stunt with a very early 12" f/4. Diagonal loosened and fell on mirror. Damage, yes! Busted diagon. Marks on mirror.

But it still worked fine. Yours will too.

#35 smee

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Posted 22 November 2012 - 12:31 PM

...and it all went downhill from there



Ayup, gravity will do that.
:lol:


I heard once a guy tried to dodge a speeding ticket blaming gravity on a downhill stretch made him go 50% over the limit!

#36 Slow Astronomer

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Posted 29 November 2012 - 05:38 PM

Sorry to hear about your mirror damage. Hopefully the damage won't affect the scopes use. Looks like you have rec'd some good advice above so I'll just leave you with this:

"Watch out for those gravity storms!" - Jimmy Buffett :tonofbricks:

Clear skies, Dave

#37 aatt

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Posted 29 November 2012 - 08:51 PM

Thanks to all the folks offering their reassurances and personal horror stories. I have never had to contend with a damaged scope in my 14 years of dabbling in this hobby as an adult-go figure that a new scope would "break" a perfect record within a week of getting it! Seeing here has been mostly mediocre, but the scope seems to be o.k. I can't tell if it is damaged, so I am encouraged by that.Conditions have been too poor for a good star test.When the seeing clears I have had some pretty amazing moments at the eyepiece. The visible detail on the moon and Jupiter this week are way beyond what my modest 6"has been able to show. So all-in all, I think the scope is working well enough to keep me pretty happy. A horrible moment, but no real obvious compromise in performance.

#38 frito

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Posted 29 November 2012 - 09:55 PM

you should be fine. the very small chip i put in my XT8's mirror i have determined to be not visible at the eyepiece so i'm leaving it alone and not even painting over it. i still know its there but i still enjoy the performance of my scope and thats what matters the most! :)

#39 nirvanix

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Posted 30 November 2012 - 07:26 PM

Life is messy. The winners clean up and move forward. ;)

My dob is an Antares (GSO). In their infinite wisdom the manufacturers hard-slapped and glued the secondary to its mount. Had it out in -40C and the glue failed. Big whack, little whack, tiny whack. Coating scratches on the mirror. Secondary had a 1/2 inch chip out of it. After my tantrum I blackened the rough spots on the secondary, remounted it with silicone dabs and to this day, even though I've replaced the mirrors with premium ones, that injured scope gave me the best view of Jupiter I ever had. For 5 seconds it looked like a Hubble photograph. I still have that secondary tucked away in the ods and ends drawer and would have no trouble calling it out again if the need arises.

#40 Mirzam

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Posted 30 November 2012 - 07:34 PM

FWIW -40 C and -40 F are the same temperature. (Some of us may not be metric savy).

http://www.csgnetwor...mpconvjava.html

At that temp I'd be more worried about some body part falling off. CCD's cameras should have very good signal to noise though.

JimC

#41 nirvanix

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Posted 01 December 2012 - 12:28 AM

At that temp I'd be more worried about some body part falling off. CCD's cameras should have very good signal to noise though.


I always do a body part count after coming in from observing in such weather. As far as I know I've still got all my bits and pieces.

#42 Mike B

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Posted 01 December 2012 - 02:10 PM

I always do a body part count after coming in from observing in such weather.



Good plan! Still, at my house, that's just the initial phase. A subsequent measure that's generally advisable is to exercise caution with said parts when crawling into bed at 0:dark:30, lest they come into contact with a sleeping spouse prior to reaching ambient temps... :bugeyes:

Feet & toes are particularly hazardous in this regard.

#43 JohnMurphyRN

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Posted 01 December 2012 - 02:13 PM

A subsequent measure that's generally advisable is to exercise caution with said parts when crawling into bed at 0:dark:30, lest they come into contact with a sleeping spouse prior to reaching ambient temps... :bugeyes:

Feet & toes are particularly hazardous in this regard.


I thought pressing said parts against sleeping spouse was the preferred method of rapidly reaching temperature equilibrium....

#44 Mike B

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Posted 01 December 2012 - 02:24 PM

As they say on the crazy video shows:
"Do not attempt this at home! Leave to the professionals"
:lol:

#45 Scanning4Comets

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Posted 02 December 2012 - 06:40 PM

I can't find the link, but there was a guy who posted his ordeal at his blog...He was usin large magnets as counterweights when, a little too close to horizon, one came unstuck and bounced off his new Zambuto mirror. He sent it to Carl for examination and about a quarter-sized spot had stress-fractured beneath the coating, makin that bit unusable. Carl's advice to him was to just cover that spot, as others here have suggested. The amount of light loss was negligible.


I remember reading that article a few years ago! it was none other than TOM HOLE himself! I stumbled upon his blog a few years ago and I have read MANY of his articles which are EXCELLENT by the way!

If you read the link to the article below he was sent a brand NEW SHINY ZAMBUTO MIRROR !!!! :bow:

http://www.tomhole.c...aster 11 EL.htm






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