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Chipped objective question

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#1 Jobryant

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Posted 20 December 2013 - 02:18 PM

Well my bad luck with optics continues. About an hour ago I had my Vixen knocked over by my 18 month old little boy. The objective now has a half moon chip about 1/2 inch to 3/4 inch long. I've checked collimation and it is fine. My question now is will the chip effect the view at all?

#2 Rutilus

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Posted 20 December 2013 - 02:23 PM

My Carton 100mm f/13 has a chip in the lens, now and again I might get the odd reflection, apart from that it performs fantastic.

#3 Jobryant

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Posted 20 December 2013 - 02:28 PM

Thanks for the reply Rutilus that helped ease the pain a bit.

#4 jbalsam

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Posted 20 December 2013 - 02:30 PM

You might consider placing some sort of black material over the chip if you do notice any issues like odd reflections.

I know that for chips and nicks (and gunshot holes) in large reflector primaries people will just black out the affected area of the mirror. All the damaged region is doing any more is degrading image quality, so it's a better solution to black it out than to leave it as is. Yes you lose light grasp, but the light that that chip is grasping is not going where you want it to go anyway.

#5 gene 4181

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Posted 20 December 2013 - 02:32 PM

you might consider calling your homeowners insurance

#6 Tank

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Posted 20 December 2013 - 03:05 PM

Too bad happened to me also! Feel your pain!
It will still provide great views thou!
You wont really notice unless you look thru the wrong end!

#7 Jobryant

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Posted 20 December 2013 - 03:33 PM

Thanks guys I'm starting to feel a bit better about it. I was able to test it out a bit and view seems to be like it should. I don't know if I'll ever be able to enjoy the scope as much as I use to knowing the chip is there. I think my kids new nickname is going to be Chip from now on.

#8 Thomas Karpf

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Posted 20 December 2013 - 04:07 PM

Just be glad it didn't fall on your son. Children can be much more expensive to fix.

#9 GeneT

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Posted 20 December 2013 - 06:17 PM

I'm afraid the chip will affect your views. Have you taken the telescope out for a test?

#10 Don Taylor

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Posted 20 December 2013 - 08:35 PM

You might consider placing some sort of black material over the chip if you do notice any issues like odd reflections.

I know that for chips and nicks (and gunshot holes) in large reflector primaries people will just black out the affected area of the mirror. All the damaged region is doing any more is degrading image quality, so it's a better solution to black it out than to leave it as is. Yes you lose light grasp, but the light that that chip is grasping is not going where you want it to go anyway.


Yes! The bullet wounds in the face of the 2.7m (107 inch) telescope at McDonald observatory were blacked out when i saw the mirror in person in 1979

#11 Jobryant

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Posted 20 December 2013 - 08:47 PM

I'm afraid the chip will affect your views. Have you taken the telescope out for a test?


Just during the day and I couldn't detect any issues caused from the chip.

#12 jbalsam

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Posted 20 December 2013 - 09:31 PM

Worst case scenario: you black out a 0.5"x0.75" section of your 114mm objective. You only lose 7.4% of your light gathering ability. Whoop-di-doo =) You'll never notice it.

#13 jimegger

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Posted 20 December 2013 - 09:58 PM

I concur with blacking out the chip with some magic marker or paint even. Use something that will not flake off. The lens will perform as if the chip were not even there except for the slight and unnoticeable light loss.

#14 Rutilus

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Posted 21 December 2013 - 07:30 AM

I'm afraid the chip will affect your views. Have you taken the telescope out for a test?


I used my Carton scope side by side on many occassions with my Tak TSA -102 and a FS-102, the planetary and Lunar
detail visible in the eyepeice was the same in all three scopes. Even with a chip in the lens, the Carton glass is good glass.
The re-sale value of the scope will be affected I'm afraid to say. That was the reason why I managed to get my Carton lens
at a very, very good price.

#15 T1R2

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Posted 21 December 2013 - 05:48 PM

if you still have the chip, then drop some fly head cement on it and stick it back on, you'll never even notice it

just use very little, not even a full drop, as you don't want the excess to push out crack onto the lens. the good thing is, if it does, fly head cement is water soluble when not fully dry. also it dries clear, so it wont effect the views once you get it in place.

#16 Jobryant

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Posted 21 December 2013 - 07:10 PM

Thanks everyone. I didn't know there were so many options for one to do for a chipped objective. Now that the initial shock has wore off I'll have to post a picture of it when I get a chance.

#17 charen

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Posted 21 December 2013 - 10:04 PM

While you may not see any visual difference you will still KNOW it's there and if you are like me it will eventually drive you nuts.
I have sold 2x classic Japanese refractor's with chipped objective lens over the years which I stupidly caused by 1/ cleaning [!] and 2/ dropping.
Every time I got the scopes out a voice inside my head said 'it has chipped glass'. In the end I could not stand it any longer ! I spent more time worrying then observing.
EVERYTIME you use the scope you will be thinking about it. People who say not to worry etc. do not realize how human psychology operates. Sorry, I know that is not helpful, but trust me it will bug you.

Chris

#18 mikey cee

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Posted 21 December 2013 - 10:50 PM

True the image may not be any less because of it but your pysche will be forever changed! You of course already are aware of this. :help: Mike

#19 Grava T

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Posted 22 December 2013 - 07:07 AM

I have a vintage 60mm Pentax refractor with both elements in the objective chipped in different places. I had a chance to swap it out for a new objective but the chipped one just performed better. Kept it in and I can't see
any effect on the image at all. Hurts more looking at it so I just try to forget about it and enjoy the views.

#20 mayidunk

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Posted 22 December 2013 - 04:51 PM

While not a refractor, I recently managed to scratch the primary on a 10" Newt. I recently got. The danged screwdriver slipped while I was adjusting the retainer clips, resulting in a squiggly scratch about a half-inch long at the edge, near the clip! Looking through the focuser tube without an eyepiece, I was able to see it. However, with an eyepiece in the focuser...? Just as if it never happened!

Let it go, it now has "mojo" (ability to bounce back from a debilitating trauma and negative attitude) going for it! :)

#21 mikey cee

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Posted 22 December 2013 - 09:27 PM

Couldn't you rotate the mirror to move the scratch behind the clip?? That's what I would do if it were mine. ;) Mike

#22 Jobryant

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Posted 10 January 2014 - 12:57 PM

Took me awhile to get these pictures posted mainly because I didn't want to look at the damaged glass. Out of site of of mind mentality. Funny thing is the scope seems to be a bit sharper then I remember before the chip. I thought for sure I was going see the opposite or at least think I was seeing the opposite but this isn't the case.

I just got back from viewing some deer and I was extremely impressed with the views I was getting. Maybe it was all in my mind or maybe the scope's collimation was a wee bit off before the fall and was knocked into perfect alignment after the fall but what are the chances of this happening. I'd bet slim to none. All things considered I am extremely pleased with the scope performance at the present time which makes it much easier to forget about the damaged objective.

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#23 Jobryant

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Posted 10 January 2014 - 12:58 PM

another

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#24 Jobryant

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Posted 10 January 2014 - 01:00 PM

another one

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#25 Jobryant

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Posted 10 January 2014 - 01:01 PM

almost done

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