Dion: If there is no structural damage to the binocular, it is most probable that one (or both) of the prism clusters has become knocked out of alignment. In the good old days, most decent binoculars had access holes in the housing to allow you to get to the adjustment screws. Many don't do this anymore, and it is as Seth posted, it is often cheaper to simply replace them than to have them re-collimated. That said, some makes and models can still be adjusted. On more than one occassion I have re-collimated the ubiquitous Chinese-made 15x70mm binocular sold as Celestron, Oberwerk, Galileo, Bear, Brunton, etc. They are all the same binocular made on the same assembly line, with the only differences being labeling, the outer rubber coating and eyeguards, and slight coating differences on the optics. There used to be a DIY article on Cloudy Nights that detailed the procedure, I'm not sure if it's still there. It's a trial and error method and can be very time consuming, but it has worked for me. I'm also not convinced that the adjustments, once made, will be as robust as the factory setting since they use a putty-like substance to hold the prisms in adjustment that hardens upon application. You have to break that loose to adjust the prism clusters and once re-aligned you'd need to apply something similar to help hold them there. You have to know where the adjustment holes are for your model and to access them it often means peeling-back the rubber "armor" to get to them. And of course you have to stick the rubber back down when done. The professionals use a dual-barrel collimator. I don't think anyone in Salt Lake has one anymore. Gallenson's did decades ago. University Optics might be a good place to call. Jan Seyfried is a binocular expert and has written on the subject. He might even have a collimator and if he can't or won't recollimate them, he might be able to suggest a shop that can. Bill Cook (former ATM Journal editor) is also a career optician with a Navy background and if you can find his number, he might be able to help, as well. Actually I'm not sure if Bill is still living but you never know. On Tue, Oct 23, 2012 at 6:58 AM, Dion Davidson <diondavidson@yahoo.com>wrote:
Does anyone have suggestions on where I can take my Bushnell 12x50 binoculars for repair? The eyes don't line up anymore, and nothing I do with the knobs and dials seems to fix it. I don't know if they got dropped or what. Each eye seems OK independently, but together they create nothing but headache because the two images are not aligned. Thanks, Dion