Are my binoculars faulty?

[ED209]

Hi All

I've just bought some cheap - well £30, they're cheaper when on at Lidl but I didn't want to wait - 10x50s and am surprised by the amount of play in the eyepieces. At all positions of focus, the eyepieces waggle left and right on the focussing bar (the bit that slides in and out to focus the binoculars) with the tiniest pressure, sliding up and down through 3mm as measured on the outside of the tubes that they slide up and down on (yeah, I've got no clue what the various components are called, sorry!)

Having only used a pair of compact 10x25s with fixed tubes (the focussing mechanism being internal) that I've grown accustomed to holding right against my eye sockets for extra stability, I wonder if my 10x50s are dodgy - I have to hold them away from my eyes to maintain focus, not sure if that is normal or not? Should I see about sending them back, or put up with it? If this is par for the course then I'm sure I can get used to it, I'm just wondering if they generally are better put-together and I've got a duff pair...

They're Adler Optics Witnesses if that makes any difference (I understand all cheap binoculars are made to similar designs in the same factory, and just branded differently).

[brantuk]

The "wigly bits" otherwise known as diopters have a twist up eye relief (if it's the same as the lidl's). These are to keep your eye off the lenses and it doesn't matter if they're a little loose. The right hand one has a wheel behind it to adjust the focus. Once set for your right eye, you then only need to use the central wheel (middle of body) to adjust focus - your left eye will be automatically tuned in. Hope that helps.

[LukeSkywatcher]

Yeah the Adler bins have screw down eye cups. Try them out at different settings because they have click stop eye cups. You will find a setting that works for you.

[ED209]

Thanks but that not what I mean - yeah the twist-up eye relief rings (that these have instead of rubber eyecups) are a bit waggly, but the whole eyepiece assembly is as well...

So when you focus them, a bar that the focussing wheel rotates on slides up and down. Stuck on the end of this bar is a hinged piece (hinged so that the binoculars can be adjusted for different nose widths) that is pushed up and down by this focussing bar. The hinge itself is pretty solid, no flex or play there but the whole hinged piece rocks left and right on the focussing bar such that when you push lightly down on the right eyepiece, it moves 3mm down relative to the body of the binoculars and the left eyepiece moves up 3mm. It's as though this hinged piece should be more tightly screwed down to the focussing bar (there isn't a screw visible or accessible - the area is covered by a rubber plug that appears glued on and I don't want to pick off in case I end up returning them, but I presume there is a screw under there).

[brantuk]

Hmmm.... that doesn't sound right I must admit - perhaps you should return them as faulty and ask for a good pair (or refund)? The eypiece assembly should be fairly firm.

[LukeSkywatcher]

Oh ok.....so when you put pressure on one EP the other moves up and i assume visa versa?

Yeah it sounds as if there is a screw between the EPs that needs a little tightening. Its most likely under the little cap you say is there that you dont want to remove.

If you really are not happy and dont want to play around with them then bring them back. Maybe the shop you bought them from can fix them there while you wait. I'm sure its just a screw thats needs a twist.

[ED209]

Thanks folks....I bought them online so returning them is a bit inconvenient, I want to be using them on the lovely clear nights we have here this week and it'll probably be the weekend before I'd get a chance to get down the post office.

I'll give the shop a call tomorrow, hopefully they'll be able to confirm whether or not they can be tightened up in the way we imagine, and if so I'm sure I'll be able to get them in a state I'm happy with.

[brantuk]

Good luck ED - let us know how you get on

[LukeSkywatcher]

I'd say that the rubber cap between the EPs pops right off and you can tighten the EPs that way. You may need to reglue it. I assume you mean the part in the below image..........marked in red:

[ED209]

Thanks, that's exactly the bit I mean (don't know why I didn't think of posting a picture, would have saved some typing ).