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How to clean NexStar front lenses?

Celestron equipment
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9 replies to this topic

#1 AlexL

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Posted 03 August 2020 - 03:20 PM

Hi,

 

Unfortunately, I have neglected my NexStar 6SE for a couple of years.

Now, it appears to have developed  some fungus on the optics frown.gif

 

Although the night sky observation looks like not to have been impaired I would like to ask what can be done to mitigate this situation.

 

 

Many thanks,

 

Alex.

 

 

 

Attached Thumbnails

  • NexStar_6SE_2.jpg


#2 trigger

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Posted 03 August 2020 - 04:14 PM

https://www.youtube....h?v=0Pi6VcH38pc

I'm a complete noob and have completed this operation. After assembly, collimated and the optics are spectacular. I understand if you feel uncomfortable doing this. If the growth is on the outside, perhaps a 50/50 mix of alcohol and water with tissue with light passes.


Edited by trigger, 03 August 2020 - 04:19 PM.


#3 whizbang

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Posted 04 August 2020 - 07:51 PM

Daub and blot, don't rub:

 

https://www.youtube....h?v=e66yIuD3cMk

 

I usually use a 3:1 mix of distilled water to alcohol.  With fungus I think I would do the first pass with bleach instead of alcohol.



#4 AlexL

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Posted 04 August 2020 - 11:01 PM

Many thanks for your replies.
I will give a very superficial try with alcohol on a small section because I feel uncomfortable.

 

Alex



#5 AlexL

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Posted 05 August 2020 - 02:22 PM

HI, just wondering if eyeglasses' cleaning liquid and cloth would be "safer" that a mixture of ethanol / water?

 

 

Alex.



#6 whizbang

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Posted 06 August 2020 - 09:52 AM

I used Windex on an eyepiece one time and cleaned the coating right off.

 

Just say NO to commercial cleaning products.



#7 AlexL

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Posted 12 August 2020 - 03:20 PM

I get sick only the thought of touching the optics and for sure I will not use Windex smile.gif



#8 gnowellsct

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Posted 14 August 2020 - 03:42 PM

I used Windex on an eyepiece one time and cleaned the coating right off.

 

Just say NO to commercial cleaning products.

You do NOT, as in cannot, remove SCT coatings with windex.  Coatings are baked into the glass.  You would need sandpaper or sulphuric acid to remove corrector plate coatings.  I'll refrain from voicing an opinion about the eyepiece because there are so many decades of production and so many manufacturers, not all of them good.

 

Here's a document:

 

How to Clean Your Corrector Plate

 

Here's a visual disassembly guide:

 

Disassembly of a C8: Child's Play  

 

p.s. Rod Mollise has been using Windex for decades and he "wrote the book" on SCT ownership.  I use Tech Spec Lens Cleaner from Edmund Optics, they know a thing or two about optics.

 

Greg N


Edited by gnowellsct, 14 August 2020 - 03:43 PM.

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#9 gnowellsct

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Posted 14 August 2020 - 03:44 PM

I get sick only the thought of touching the optics and for sure I will not use Windex smile.gif

You could do worse.  You could not touch the optics and leave that junk on....I'm pretty sure that's mold, it would be a serious error not to clean it.  Mold can etch glass in the extreme case.  


Edited by gnowellsct, 14 August 2020 - 03:44 PM.


#10 gnowellsct

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Posted 14 August 2020 - 03:50 PM

Watch these spectrum coatings videos and disinhibit a bit

 

https://youtu.be/JMH0WQETxKw?t=2

 

https://youtu.be/_ToAkH7u3lY


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