Seeing double through binoculars

[phill28]

Hi all,

Up until now my 10x50 porro binoculars have been fine. went to use them couple of days ago and for some reason i am seeing double through them and nothing i do seems to rectify this problem. Also have the same problem with my 10x50 roof prism binoculars. I wear glasses but dont use them when observing because i can never seem to see anything through binoculars.

Any ideas as to what could be wrong????.

Many thanks for any help/advise.

[chops]

I'm taking apart a trusty pair of Tasco Offshore 54 8x40 which have the same problem; they've probably had a little knock which cause the prisms and lenses not to align perfectly. If you're lucky then your binos will have obvious screws to adjust the prism alignment etc.

Google binocular collimation.

[chops]

Actually, I really do have these in pieces right now. If I fix it, maybe I'll document and post later.

[chops]

I'm sure there are plenty of great articles on SGL, but I've found this good read: http://www.cloudynights.com/page/articles/cat/articles/how-to/“collimating”-binoculars-r408

[chops]

Damn, I wish I could edit posts (I don't believe possible until 250 or mod status)

try again: http://www.cloudynights.com/page/articles/cat/articles/how-to/“collimating”-binoculars-r408

[ronin]

Somewhat odd as it has occurred on both binoculars and there is little chance that both would suffer the same problem.

You may be able to adjust the porro prism ones but I am not sure about the roof prism ones - porro's are a single prism but roof's are 2 prisms. If they are 2 prisms glued together then adjustment sounds possible if they are 2 sepearte prisms then I suspect not.

[phill28]

Cheers guys for the advice

Shall have a look later at collimating the porros.

[Charic]

Try some new binoculars from a high street store. If there is still a problem, there is the need to see your optician. As ronin points out, very strange that BOTH binoculars are giving the same result, whereas......"up until now, they have been fine?"

[Digger1895]

Since this has happened to both pairs at the same time you need to look for common factors, have you visited an optician lately ;0)