Binocular problem? Maybe?

[MarkMayf]

To cut to the chase, I don't know if I have a problem with my binoculars or not or if this is normal.

I have a pair of Helios Quantum 4 15x70s, when using them for astronomical viewing especially I am having focus problems.

Looking at a bright star for example, the left side never reaches a sharp focus. However the right side can be focused to a sharp point using the dioptre adjuster.

Is this normal or a third pair of binoculars I need to send back?

Thank You

[BinocularSky]

You should be able to focus both sides but if you have myopia (short-sightedness), some binoculars do not have sufficient travel "beyond infinity" (for normal/corrected vision) to be able to accommodate it. The fact that you can focus the right side using the right eyepiece dioptre adjustment suggests that this may be your problem (were the other returns due to the same problem?), but it may also be a quality control issue at United Optics (QC is minimal except on their premium binoculars).