OpticsTalk by SWFA, Inc. Homepage SWFA     SampleList.com
Forum Home Forum Home > Other Optics > Binoculars
  New Posts New Posts RSS Feed - Damaged lens coating?
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Visit the SWFA.com site to check out our current specials.

Damaged lens coating?

 Post Reply Post Reply
Author
Message
seafarer View Drop Down
Optics GrassHopper
Optics GrassHopper


Joined: December/16/2018
Location: seattle
Status: Offline
Points: 3
Post Options Post Options   Thanks (0) Thanks(0)   Quote seafarer Quote  Post ReplyReply Direct Link To This Post Topic: Damaged lens coating?
    Posted: December/16/2018 at 22:07
I have a pair of fujinon 7x50 marine binoculars. There is damage to the eyepiece lenses, seems like the coating has turned into a hard cloudy mottled film. I think this was from salt water spray, and many hours in the hot sun. I have tried to remove it with: lens cleaning solution, iso alcohol and water, vinegar, lighter fluid, and finally 99.8% ethanol. Nothing takes it off.

Scrap it all? More aggressive solvent, like MEK or xylene?

Any suggestions appreciated.

Not sure how to post a pic of the lenses.
Back to Top
vinn View Drop Down
Optics GrassHopper
Optics GrassHopper
Avatar

Joined: November/23/2018
Location: wa. state
Status: Offline
Points: 24
Post Options Post Options   Thanks (0) Thanks(0)   Quote vinn Quote  Post ReplyReply Direct Link To This Post Posted: December/17/2018 at 08:47
   are those lenses glass?   many lenses today are plastic, but will withstand isoproponal.   on glass lenses ( removed from the housing) i use acetone --- it may melt plastic.   good luck.  vin   
vin
Back to Top
mike650 View Drop Down
Optics God
Optics God
Avatar

Joined: May/14/2006
Location: West of Rockies
Status: Offline
Points: 13737
Post Options Post Options   Thanks (0) Thanks(0)   Quote mike650 Quote  Post ReplyReply Direct Link To This Post Posted: December/17/2018 at 09:06
Maybe WJC (Bill) will chime in.
Fish to Live, Live to Hunt
Back to Top
WJC View Drop Down
Optics Apprentice
Optics Apprentice
Avatar

Joined: May/28/2014
Location: Twin Falls, ID
Status: Offline
Points: 268
Post Options Post Options   Thanks (1) Thanks(1)   Quote WJC Quote  Post ReplyReply Direct Link To This Post Posted: December/17/2018 at 10:56
Roger, that.

I don’t think the cheapest Fujinon would use plastic on an eyelens; that kinda’ thing is for the Bushnell Ensign. I learned about that the hard way!

Judging by all you have used, I’m at a loss. I have removed more than a spoonful of salt from a MK28 (left hanging over the rail on a flying bridge ... by the skipper.) Lens cleaner, De-solv-it, and acetone are virtually all I ever needed to clean so many lenses.

Replacing the lens (a doublet) will be cheaper than buffing and recoating.

I would send you to David, at Captain’s in Ballard. But 121-year old Captain’s sold in 2014 and I know much of their direction in optics has gone away. Also, I taught David much. But, that issue—in that severity—never came up. The closest other place with real techs is Baker Marine in San Diego. If you send your Fujinon to New Jersey to have it repaired “right,” they just send it to Brian at Baker, anyway, as Baker is Fujinon’s OFFICIAL US fixery. (Don’t bother looking it up ... it’s a Bill Cook word.)

Your best deal is a little further away at S.O.R. (Suddarth Optical Repair) in Henryetta, OK. Cory saw a binocular ... once ... in a magazine, but I’m sure the price would be right. We were Opticalmen aboard USS Grand Canyon and for 7 year he kept me from having to chip a nail at Captains.

Please let us know what you decide.

Bill    


"What lies behind you and what lies before you are tiny matters compared to what lies within you."—Ralph Waldo Emerson
Back to Top
capecod View Drop Down
Optics GrassHopper
Optics GrassHopper


Joined: May/26/2015
Location: cape cod ma usa
Status: Offline
Points: 1
Post Options Post Options   Thanks (0) Thanks(0)   Quote capecod Quote  Post ReplyReply Direct Link To This Post Posted: August/22/2019 at 19:25
if you can find some ...try a tiny bit of cerium oxide with acetone...g l
Back to Top
seafarer View Drop Down
Optics GrassHopper
Optics GrassHopper


Joined: December/16/2018
Location: seattle
Status: Offline
Points: 3
Post Options Post Options   Thanks (0) Thanks(0)   Quote seafarer Quote  Post ReplyReply Direct Link To This Post Posted: August/26/2019 at 23:09
Thanks for the suggestions.

I tried Acetone a while back as a last effort to remove the damaged coating from the glass lenses. It did begin to work. Despite being pretty careful, the plastic lens carriers got slightly melted where the lens joins, making the problem even worse. I suppose attempting to fully remove the lenses from the carriers is possible, but I think involves some tricks (inert gas in the space between the lenses). I am pretty adventurous, but that looked daunting. Ended up giving the parts away to a shop for spares.

I bought a new pair of Fujunon Mariner 7x50 WPC-XL Porro Prisms. I don't like them as much as the old style more adjustable ones.

In the end I would not recommend attempting to remove a damaged coating yourself. The estimate for professional repair was a high percentage of a new pair, not worth it to me. I could not find anybody willing to sell new lens and carrier assembly. Interesting to learn how binoculars are assembled, so I'm smarter, and much more careful.
Back to Top
3_tens View Drop Down
Optics Jedi Master
Optics Jedi Master
Avatar

Joined: January/08/2007
Location: Oklahoma
Status: Offline
Points: 7743
Post Options Post Options   Thanks (0) Thanks(0)   Quote 3_tens Quote  Post ReplyReply Direct Link To This Post Posted: August/30/2019 at 10:08
With mass produced, short run products, replacing is the best option. Technology is advancing so rapidly in lens coatings. Especially in the lower to mid range optics. Same money will replace with a much better product in the established name brand lines.
Folks ain't got a sense of humor no more. They don't laugh they just get sore.

Need to follow the rules. Just hard to determine which set of rules to follow
Now the rules have changed again.
Back to Top
WJC View Drop Down
Optics Apprentice
Optics Apprentice
Avatar

Joined: May/28/2014
Location: Twin Falls, ID
Status: Offline
Points: 268
Post Options Post Options   Thanks (0) Thanks(0)   Quote WJC Quote  Post ReplyReply Direct Link To This Post Posted: October/09/2019 at 19:42

Comparing a binocular with magnesium fluoride coatings on all glass-to-air surfaces to the same instrument with today’s multi-coatings, an observer may experience an increase in light transmission of 13% or slightly more. But when comparing the multi-coatings of two leading manufacturers the difference is so small as to be inconsequential. Frequently, when an observer suggests (or insists) one manufacturer’s coatings are “noticeably” superior to those of another brand of similar quality, the difference he or she is seeing probably relates more to baffling, prism shields, edge blackening, size and position of the field stop, knife-edge on that stop, prism type, slotted prisms (in Porro prism instruments), smoothness of surfaces, configuration of the eyepiece, and other considerations than coatings alone.

"What lies behind you and what lies before you are tiny matters compared to what lies within you."—Ralph Waldo Emerson
Back to Top
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.01
Copyright ©2001-2018 Web Wiz Ltd.

This page was generated in 0.180 seconds.