Here is a quick tutorial on how to focus a pair of binoculars.
Step1: Remove the ocular lens cover
Step2: Remove the left objective lens cover
Step3: Look through the left ocular lens at an object roughly 50-100 yards away
Step4: Use the center focus knob to focus on the distant object
Step5: Close the left side objective lens cover and open the right side objective lens cover
Step6: Look through the right ocular lens at the same object roughly 50-100 yards away
Step7: Use the diopter ring to bring the distant object into focus
Step8: Open the left objective lens cover
Congratulations you have just focused a pair of binoculars. From this point on, use the center focus knob to fine tune the focus when viewing objects at varying distances
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