Anything wrong with my new Kowas? (1 Viewer)

Hello. I'll preface by saying this may be a dumb question.

I just bought a pair of Kowa 6x30 YFs for my 4-1/2-year-old son. I pulled them out of the box and focused on some stuff in the corner of my kitchen, and everything seemed fine except for a small spot of light (really, a circle of brightness or shininess) in the left optic. This spot disappears in other situations. Now I've noticed that my other binoculars exhibit the same kinds of spots in some lighting situations (testing in the same interior lighting). I confirmed that using a clean lens cloth on the Kowas didn't make a difference. I'm assuming this may just be a speck of dust on an interior lens surface or prism, but I don't know enough about optics to be sure. Bottom line is that out in the field, I haven't noticed anything like I see indoors, and the pair seems to be working fine.

I got an RMA for a new pair, but now I'm thinking it might just be me being paranoid. Is there anything wrong with this pair, or are these kinds of lighting artifacts common in all binoculars, and nothing to worry about? More to the point, can I expect the same in any new pair, particularly at this price point?

Thanks.

Welcome to the forum.

It doesn't sound to me like there is anything to particularly worry about, most likely a spurious reflection/refraction from one of the interior lights. It's the sort of think that usually gets noticed when the sun is at a particular angle to the objectives when low in the sky. Few binoculars are totally immune to such things and I've certainly seen it with a $2000 Swarovski. Though certainly not ideal, I'd consider it much more acceptable with a $100 Kowa.

Hope that helps,

David

Another welcome to the forum!

My first thought was the same as mentioned by David.

While viewing to recreate the light source, continue to hold with one hand but take the other hand and use it to shield any stray light that may be entering from the side between your face and the eye piece. Do the same with the other side. Also, take something like a note pad and move it around the front objective lens to act as a shade. If the light source goes away while doing this exercise, then the issue is a result of stray light. That is not an uncommon problem and may not be a problem outdoors under most conditions.

Thanks, David & Bruce. I'll do a little more testing, but I think what you're both saying confirms my thinking - that what I'm seeing isn't out of the ordinary, and that it wouldn't be solved by getting a replacement pair. Since it didn't seem to be a problem in the field, I think I can just forget about it.

When I see a spot that depends on the lighting,
it's some little bit of something on the field lens of the eyepiece.
That would be internal. I'm used to taking things apart and fixing it,
but that's on older binoculars, and most of them are easier to work on
than the new ones. I wouldn't expect it on any binoculars that are new,
whatever the price. Still, if it's rare to see it, it may be a matter of just moving on.
You can look through one barrel then the other under glaring conditions
(dunes, snow, etc) and see if it affects overall contrast.
That's all I'd worry about.