Question on odd problem with my Zen Rays (1 Viewer)

[bkrownd]

I have some Zen Ray 7x36 ED2 from 2010. Behind the objectives, more one side than the other, they're developing an opaque rainbow pattern around the edges. It suddenly got worse during a very rainy and sweaty outing last weekend. I'm wondering if this is water wicking into a gap between some of the lenses? (Since I'm in the rainforest my binocs are exposed to about equal parts precipitation and sweat. Goes with the territory...)

 

[perterra]

Sounds like moisture,

 

[peatmoss]

I agree with Perterra. I think it's probably moisture. Although lens separation can look rainbow-ish too. Does it grow/shrink with the humidity level?

 

[bkrownd]

Well, there was a noticable jump in the area effected on the last soaked outing I had. If it is moisture wicking between lens elements then packing it in dessicant probably won't get that out. I wonder if it's getting in through the bottom or the sides...

 

[Binastro]

. ED Glass is usually more fragile than more usual glasses.
To me it sounds like a doublet lens that is beginning to separate.

Fluorite crystals actually can become opaque due to moisture, but I don't know if this will happen with a non-fluorite crystal glass.

If the binocular is guaranteed waterproof and under warranty then I think it should be returned for complete refurbishment or replacement.

Early Canon 300 mm F2 .8 lenses suffered very badly if moisture got into the fluorite crystal and the second-hand value is approximately zero.

With special glasses great care is normally taken to exclude moisture, and the special glass is usually internal.
Modern multi-coatings help a lot to protect glass but I suppose in some cases all the precautions don't work.

I'm very wary of buying second-hand spotting scopes and Astro scopes with fluorite elements, as they could have picked up moisture in the exotic element.

 

[bkrownd]

Thanks for the input - I finally took a photo to post. The effect appears slightly more opaque in person than in the photo below, due to the amount of light needed to get decent a photo of it.

See the picture here:

 

[Binastro]

Youngs fringes?
Separation of objective elements, partially?
I have seen similar from a dropped and damaged/chipped prism on a 10x70 monocular.

If under warranty, I think a good claim.

 

[peatmoss]

Hi bkrownd. Looking at your photo, it looks more like lens separation than moisture. But either way, I believe that you need to return it to ZR for warranty service. This isn't an issue that will get better by itself. It's also probably best to send a PM to Charles to let him know what is going on, maybe even provide a link to this thread. Good luck!

 

[bkrownd]

Thanks to everyone here for the input. After bird survey season ended I sent them back to Zen-Ray, who resolved the issue.

 

[ads]

What was Zen-Ray's explanation of the problem?

 

[bkrownd]

They just replaced it. No post-mortem info.