Celestron Skymaster 15x70 question

[medwatt]

Hello,

My bin arrived today and was out of collimation. However, with the help of some online tutorials I was able to get the refractors into alignment (as far as I can tell). The problem is when I pull the objective lenses apart or closer I seem to loose collimation. I wonder if this is a normal since the binoculars look perfectly collimated when the two objective lenses are in neither extreme positions. Or should I move them far apart and recollimate ?

Thanks

[bobmoss]

I wouldn't expect them to go out of collimation when you move them apart (unless you are looking something fairly close? Make sure you are setting them up on an object very far away). I would say that if you are just using them for yourself, get them to the right distance apart and the re-collimate them for that position.

[BinocularSky]

This is very common. You have achieved what is called "conditional alignment", ie it is conditional on not changing the IPD. It happens because the optical axes of the tubes are aligned with each other at the IPD you were collimating for, but they were not aligned to the axis of the binocular hinge so, when you change the IPD, the optical axes misalign. To achieve proper collimation you need to use a proper collimator.

On the batphone, so expect weird autocorrect

[Steve Ward]

As they were new you should have sent them back immediately ... 

Now you have invalidated the warranty you will be stuck with them.