GeneT
Ely Kid
   
Reged: 11/07/08
Loc: South Texas
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Re: 22 Nagler T4 especially prone to coating defects?
[Re: slack]
#5568227 - 12/12/12 08:23 PM
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If I can locate the pics in the future (they are on a different computer), I will post pics of eye lens coating failure on a Nagler 31mm T5.
Show us the pics so we all know exactly what you are talking about.
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slack
sage
   
Reged: 05/02/12
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Re: 22 Nagler T4 especially prone to coating defects?
[Re: GeneT]
#5568515 - 12/13/12 12:20 AM
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This is the only pic of the Nagler 31mm T5 with bad coatings that I can find at this time. The portion in the reflection of the lights, that appears bright white, had recently flaked off when that pic was taken (hence the sharper edges of that patch).
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GeneT
Ely Kid
   
Reged: 11/07/08
Loc: South Texas
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Re: 22 Nagler T4 especially prone to coating defects?
[Re: slack]
#5570053 - 12/13/12 10:13 PM
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This is the only pic of the Nagler 31mm T5 with bad coatings that I can find at this time. The portion in the reflection of the lights, that appears bright white, had recently flaked off when that pic was taken (hence the sharper edges of that patch).
Thanks for posting the picture. I am sure that there are some who are qualified will evaluate and comment on the condition of lens.
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slack
sage
   
Reged: 05/02/12
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Re: 22 Nagler T4 especially prone to coating defects?
[Re: GeneT]
#5570154 - 12/13/12 11:37 PM
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Thanks for posting the picture. I am sure that there are some who are qualified will evaluate and comment on the condition of lens.
You're welcome. Though having worked with and evaluated professional lenses for nearly 25-yrs, I regard myself as qualified to identify something so conspicuous as failed and flaking coatings. And, as I've said numerous times now, I got a concurring opinion from Tele Vue on this matter when I still owned the eyepiece.
It is what it is. An example of an uncommon issue.
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Eddgie
Postmaster
   
Reged: 02/01/06
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Re: 22 Nagler T4 especially prone to coating defects?
[Re: GeneT]
#5570511 - 12/14/12 09:20 AM
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I agree that this picture shows coating flaking off.
The previous picture though looked like a dirty eyepiece.
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Starman81
scholastic sledgehammer
   
Reged: 03/06/08
Loc: Metro Detroit, MI, USA
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Re: 22 Nagler T4 especially prone to coating defects?
[Re: Eddgie]
#5570687 - 12/14/12 11:27 AM
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Thanks for the input on the issue that I faced. I had researched CN and found some threads on cleaning with acetone that some of you had also posted in and considered cleaning the 22 Nagler with it. However, reading the precautions about what acetone could do to the eyepiece if not applied very carefully, I resisted, especially because the seller was allowing me to return it. I did not want to take the risk of potentially damaging the eyepiece with any potentially harsher cleaning methods.
With that being said, I found the Nagler 22 an excellent eyepiece (the one night I had it out) and the dirt/grime whatever may have been on the eyepiece did not affect the views in any way that I could tell. On that night, I was able to observe the E and F stars of the Trap for the first time with the 22 in the focuser, I attribute that to the amazingly steady seeing that night but it goes to show that whatever was on that eyepiece couldn't have been holding it back, in terms of performance, much if at all.
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Eddgie
Postmaster
   
Reged: 02/01/06
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Re: 22 Nagler T4 especially prone to coating defects?
[Re: Starman81]
#5570811 - 12/14/12 12:53 PM
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The key to using acetone is to be very sparing with it.
Apply it sparingly to a cotton schwab and use light pressure to scrub the spot itself. Be generous with the schwabs. They are cheap.
If you put so much on the schwab that it squeezes out when you touch the glass, you have put to much.
Never apply any cleaner of any kind directly to the lens. The cleaner can be wicked up by the retaining part of the housing and get into the space between lenses.
Only apply to the cloth or schwab, and only a tiny amount. And when it is no longer showing on the glass, get a clean schwab and apply a tiny amount of acetone and go again.
Or, do as you did and just leave it alone.
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stevetaylor199
sage
   
Reged: 09/21/11
Loc: SE Wisconsin
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Re: 22 Nagler T4 especially prone to coating defects?
[Re: Eddgie]
#5570975 - 12/14/12 02:54 PM
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The cleaner can be wicked up by the retaining part of the housing and get into the space between lenses.
Is that the concern involved when using acetone, as mentioned above? Or is there another reason?
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Starman81
scholastic sledgehammer
   
Reged: 03/06/08
Loc: Metro Detroit, MI, USA
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Re: 22 Nagler T4 especially prone to coating defects?
[Re: stevetaylor199]
#5571012 - 12/14/12 03:20 PM
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I also recall reading that it can dissolve plastic and that it is highly flammable.
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csrlice12
Post Laureate
   
Reged: 05/22/12
Loc: Denver, CO
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Re: 22 Nagler T4 especially prone to coating defects?
[Re: Starman81]
#5572386 - 12/15/12 11:12 AM
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But you can do your nails AND clean your eyepieces.....
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Starman1
Vendor (EyepiecesEtc.com)
   
Reged: 06/24/03
Loc: Los Angeles
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Re: 22 Nagler T4 especially prone to coating defects?
[Re: csrlice12]
#5572418 - 12/15/12 11:29 AM
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It helps to mention here that we are talking reagent-grade acetone, not fingernail polish remover. The former is pure, while the latter has lanolin and food dye and other junk in it you wouldn't want on your lens.
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