Monday, May 28, 2012

Collimating the Orion WorldView 10x50 WA Binoculars


In January of 2011 I purchased a pair of Orion WorldView 10x50 WA nitrogen-filled binoculars from ebay. My old trusted Oberwerk 7x50’s were stolen in Flagstaff, AZ a few months before.
Unfortunately, when they Orion’s arrived, I found them to be horribly out of collimation. I used them a little during day time, sometimes with one eye shut. But for star-gazing, they proved impossible to use. I could only use them as monoculars!
I searched the web for any tips on how to collimate them, but could not find any guided instructions for accessing the hidden collimation set-screws. These binoculars have a nice feel to them as they are rubberized, but due to the rubber skin, the collimation set-screws are not readily accessible. Orion customer support told me to use a hair-dryer to heat up the rubber casing to loosen it up, but they said they do not have any instructions for collimating the binoculars.
After getting helpful insights from several articles describing the pros and cons of collimating binoculars by tweaking the collimation screws, I decided to take the plunge and try to figure it all out myself. (There seems to be a strong religious divide between those who completely oppose touching the collimation set-screws, and those who consider it a valid option.)
I hope this article helps others whose Orion WorldView 10x50 WA binoculars have received a bump and become slightly un-collimated. Severe collimation problems cannot be resolved using this method.

Collimation Instructions

DISCLAIMER: The author of this blog will not be responsible for any damage or undesirable outcome from following the instructions herein. Follow the instructions at your own risk.
Here are the instructions for accessing the collimation set-screws in the Orion WorldView 10x50 WA binoculars:
The second collimation set-screw is hidden under the rubber flap next to the focus knob. (I call this the second set-screw because an article on Cloudy Nights website refers to them as such.)
Peel up the rubber flap covering the second collimation set-screw and bend the flap upward.
Tweaking this screw will move the image along one axis (probably between top left and bottom right.) Both The set-screws are rather difficult to turn, perhaps they are in rubberized screw holes to prevent the nitrogen in the body from leaking out?
The other (first) collimation set-screw is near the eye-piece, hidden under the rubber casing, where you hold the binoculars with your hand while observing with them. It is not accessible as it is. I had to make a cut in the rubber casing along the edge close to the eyepiece, as shown in the picture. After finishing the collimation I plan to glue the rubber casing back and I am confident that the cut will be hardly noticeable. I hate to take such drastic measures, but in this case it was either this (evil) action, or throw away the binoculars and shell out more $'s for a new one (worse evil). You can hold-off on cutting the rubber casing, and just try tweaking the second set-screw. Hopefully you will achieve good-enough collimation without having to touch the first set-screw.
After making the cut I peeled up the rubber flap on top, and found the first set-screw hole. Turning this set-screw moves the image along the other axis, orthogonal to the axis of the second set screw.
To properly collimate the binoculars, they must be mounted on a binocular mount, and trained on a faraway object. The best target is a star that is not very bright. So I mounted the binoculars on my home-built binocular mount and focused on a star near the North Star, so that the star field would move little during my collimation episode.
My home-made binocular mount shown here with the good-old Oberwerks that I lost.
My binocular mount is the coolest mount ever! It provides two-axis mirror movement centered near the center of the mirror.
During the collimation process, sometimes I had both eyepieces focused properly, and sometimes I used the right eyepiece diopter to un-focus it so my brain would not merge the two images together (so I can detect small collimation errors). After a few tries, I was able to achieve good collimation with very small eye strain. Now I see single stars instead of pairs of stars! Woohoo!
The exit pupil after the collimation shows round pupils, and no cat's eye, although there is some obstruction in the view around the edges. So, the light path is less than perfect, but I can live with the small light loss. Look out stars, here I come (wife and kids permitting).


  1. Thank you thank you thank you and THANK YOU! I will try this today

  2. gracias por su explicación me gustaría saber si alguien lee esto y alguna ves ha observado con espejo de montura me cuente su experiencia gracias.

  3. Thank you so very much! I applaud you for the amount of research taken to develop a instructional procedure with visual images that anyone can follow successfully! Thanks to you, happily I was able to repair/ restore my binoculars vision to perfection at ZERO cost! Cheers