Double vision?

[scogyrd]

I bought some cheap 15x70s the other day and when the cloud cleared for 10 minutes last night I decided to try them out. The trouble is that when I look through them I can't get the image to merge and see 2 of everything, I don't seem to have this problem in the day though, any ideas what could be causing this?

I have some other bins and don't have any trouble with them so I'm presuming it's the new binoculars???

[argonaut]

These are out of collimation. Just take them back for exchange. I know some binoculars can be collmatable but why bother,return them.

It's surprising that sometimes the brain/eye can cope with horizontal miscollimation but not vertical. You would end up with eyestrain and a headache though.

Glen.

[Moonshane]

it could be collmation but I find that although fine in the daytime my 10x50s seem to show double vision at night unless I mount them - then they are spot on. if you are handholding the 15x70s it might just be this. try sitting in a chair and resting your arms on the armrests or lay down on your back / or even mount them. does this help?

if not then you'd either need to send them back or try and collimate them - the former if under warranty. if you google 'collimating binoculars' then you'll find something which may help if you need/want to try. Most can be done.

[scogyrd]

Unfortunately they were just as bad on my mount as they were hand-held.

As they were only cheap I might try collimating them myself, if that's the problem. I'd sooner not send them back if I don't have to, especially if there is a chance the new pair might be just as bad.

I suppose I could ring the supplier first and see what they have to say though.

Thanks for your help.

[scogyrd]

I just rang the supplier and the first thing he said was it sounds like they're out of collimation because they've probably had a knock in transit, and to ring back on Monday and they'll arrange for them to be replaced.

Once again thanks for your help everyone.

[scogyrd]

I just thought I'd update this to say I got my replacements and they are much better than the first set.

All in all I think the bins are well worth £50, and telescope house were a pleasure to deal with.

[LukeSkywatcher]

Telescope House really are a joy to deal with.