Double Vision with 10x50's

[DazzaB74]

Hello,

I got some 10x50 binos for Christmas and have been lucky enough to have some clear skies of late so decided to eventually give them a go.

I followed the instructions and no matter how hard i try i still get a double image of the moon or anything else i look at.

If i close one eye and focus the detail is quite good, but maybe not as good as it should be?

I admit i am probably not the steadiest of handed people, but not sure if this is the complete problem?

Any advise would be greatly appreciated.

Thanks!

[BinocularSky]

Sounds like they are out of collimation. If they are under guarantee, have them replaced. If not, you can have a go yourself (likely only to achieve "conditional alignment" -- i.e. conditional upon the inter-pupilary distance -- IPD - setting). Various details on the web.

[West End Wendy]

I knocked a pair of Binos horribly out of collimation (stepped on by a medium-sized child). I assumed they were a write-off but then I realised that one of the tubes containing the objective lens had simply un-screwed and was hanging out at a strange angle. I unscrewed it completely and screwed it back in straight. All working again.

Of course your binoculars may be designed differently but it's worth a look.

Tim

[Cellarman]

Try sitting at an open window with your elbows resting on the windowsill and focus your binoculars on a distant object. Close one eye then the other to see if both are in focus. If one eye is not focussed then you need to alter the dioptre adjustment. Usually, this means focussing the left eye with the main focus wheel, then (without moving the focus wheel!) moving the dioptre adjustment on the right eyepiece until that one is in focus too. If you have them, fit an objective cover to the occular not being used rather than trying to squint with one eye closed during this adjustment.

If, after you have done this there is still double imaging, then it looks likely that your binoculars are out of alignment and need recollimating. If they're new, don't try it yourself, return them to the retailer for repair/replacement.

Be warned - there are many people who are unable to see a double image through binoculars even when hugely out of alignment and quite often sales assistants are like that, so don't take any nonsense!