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Interviews with Optics Repairers: Bill Cook (1 Viewer)


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Here is the fourth in our series of interviews with binocular repairers, and this time we will be speaking to our good friend Bill Cook, who is once again entering into the world of optics repairs.

Troubador: Hello Bill, and first of all, thank you for agreeing to take part in this interview. While many of us will feel we know you a little through your contributions to Birdforum in recent years, as this is a new venture we would like to start from first principles, so please give us some background on yourself.

Bill: I’ve been married for 42 years and have 3 grown children. My interest in optics started in 1959 at Boyd School, a one-room school just south of Mt. Hermon, Kentucky. I was a second grader. I’ve earned a BA in Mass Communications (Radio/TV and Journalism) from Arkansas State University, and a BA in History from the University of Washington.

Troubador: And what about your career afterwards?

Bill: I was in the Navy then Naval Reserve rising to the rank of Chief Opticalman for a total of 20 years and received a commendation for professional achievement from the Army and a Navy Achievement Medal. I’ve been told that the graduation from the Navy’s Opticalman “A” School was the equivalent of an AAS in Applied Optical Technologies. As well as repairing, restoring, calibrating, and collimating a wide variety of optical and navigational instruments for 20 years in the Navy, I have done so for the Navy Reserve, Puget Sound Naval Shipyard, Joint base Lewis-McChord, and the Department of Defense, I put in 21 years’ service at Captain’s Nautical Supplies in Seattle doing the same kind of work. I have published 4 books on optics and contributed to others, written 260+ magazine and Internet articles, and for 10 years published Amateur Telescope Making Journal. I have been fortunate enough to have some of my coined terms added to the vernacular of binocular engineering by SPIE (the Society of Photo-optical, Instrumentation Engineers, have suggested a couple of routines in Zemax lens design software, and designed Captain’s all-brass Baywatch telescope and the long-focus Houghton telescope featured in ATMJ #4. I guess you could say I am a time-served veteran of optics and optical repairs.

Troubador: Tell us about your new optical repair venture.

Bill: It is called Collimation Plus and is based in Twin Falls, Idaho and I am the sole employee at the moment. The name is derived from the fact that, across the board, collimation issues are the biggest concerns for most observers.

Troubador: Binoculars have changed over the decades. Will you be accepting binos from all eras and all brands, or will you specialise?

Bill: Brands mean nothing in this context and eras very little. I have repaired and collimated just over 12,000 binoculars and repaired optical instruments from all eras going back to the 18th Century. I’ve also done restoration for the Smithsonian Institution and optical engineering for the University of Chicago’s Yerkes Observatory, C. Plath Navigation, and Orion Telescopes and Binoculars. Not to make grand claims, for which I am famous, but most binoculars have passed through my hands already and I am comfortable with tackling any that are likely to come my way.

Troubador: Some binoculars require special tools and of course you need a collimator. Is your business fully equipped with regard to tools and spare parts?

Bill: There are several parts to that question so I will offer several answers. First, I have most of the tools including a Navy Mk5 Collimator, and secondly, one of the prerequisites for getting a seat in the Navy’s Opticalman program is having a high mechanical aptitude, which is necessary when delving into the depths of optical instruments. Third, regarding spare parts, clearly, I am not starting out with the parts inventory I had built up at Captains, I don’t have nearly as many. However, I have a list of contacts who I will be contacting to re-establish some of my connections. I haven’t contacted Toshi Kamakura since he took the company over from his dad, but he has been very helpful for getting needed parts and pieces for me.
Also, a large part of my business will be buying binoculars from eBay to recondition, collimate, and resell. I will be buying good binoculars—no “Zip, Zoom, Insta, Perma, Auto-Focus,” or “ruby coated”—instruments. And then after inspecting, reconditioning, and collimating selling them to buyers with more maturity and financial wisdom than vanity. For example, I have a brand-new Bushnell Legacy 8x40 with Zirconium Dioxide AR coatings that looks like it just rolled of the assembly line and was never touched. The image is sharp and bright, and I’ll be selling it for about a third of its original cost. Also, being familiar with the English language, I will not advertise any as (drum roll please ... “VINTAGE.” The word is dramatically over-used and in about 98% of the cases, an inaccurate sales gimmick! Most will have all they need to have. With those, collimation is the big issue. Fourth, at this moment I do not have a re-gassing setup. But between 1995 and 2008, I worked on several instruments that I did not re-gas with dry nitrogen at the request of the owners, who didn’t want to spend the extra dollars. In that time, not one instrument was returned due to fogging, although most were being used by the Alaskan Fishing Fleet in very demanding conditions, certainly more demanding than the conditions experience during birding or observing nature. If an instrument is correctly sealed ... it’s sealed.

Troubador: Be polite when you comment on this: repairs done at home by people having a go, maybe trying to save money.

Bill: If being “polite” means bending the truth to be “politically correct,” well, you know I won’t go there.

“The truth is incontrovertible. Malice may attack it; ignorance may deride it. But in the end, there it is.”— Winston Churchill.

Usually homebrews make things worse causing the observer to end up with a more costly repair. I frequently see binocular parts arrayed out on tables and work benches. I am glad to see a budding new generation of potential techs. But there is a big difference between taking an instrument apart and collimating it once it’s back together. And currently, the many “collimation tips” on the Internet deal with CoAl (conditional alignment) only and not clinical 3-axis collimation. If I say, “don’t do it, leave it to me,” it sounds as though I am trying to snag work for myself. I’m not. If you leave it to me, there will be less work to do, the job will not take as long and it will cost you less. I have spent years doing freebees—on simple projects like cross threaded objective bell housings—many other techs would have charged for, giving away parts and, in the days when I had money, sometimes new binos.

Troubador: Folks save up to buy whatever binocular or scope they can afford or feel they need or want. It is understandable that they get upset if the lenses get scratched. What can you do for them?

Bill: You know, in most cases the scratches have no noticeable effect on the optical performance, so usually my advice is to admire what you are looking at through the instrument and don’t agonize over the instrument itself. Major scratches mean returning the instrument to the manufacturer or importer. Often a new instrument is the most cost-effective solution. If it is really a scratch—as opposed to a sleek—It must be ground out, then buffed (both of which will probably change the prescription) and then take a trip to a coating house, $$$$. But I can understand it when an instrument has become an old friend that you still love and want to use.

Troubador: I guess most instruments coming to you will be out of warranty, is that correct?

Bill: For the most part, yes, although there are folks out there who would rather trust their repairs to a time-qualified technician than the unknown qualities of a “start-up” bino brand. I could mention Zen-Ray at this point. Finally, I will discourage working on ZOOM binoculars. I learned early on at Captain’s that some people expect a repair technician to magically make up for their poor buying decision.

Troubador: Finally Bill, when you receive an instrument will you inspect it and then send a quotation to the customer, listing and costing the work required, for them to respond to? And you will let them know the moment the repairs are completed?

Bill: Yep!

Troubador: Bill, thank you for taking the time to give us insights into the world of optical repairs, and good luck with your new venture.

Collimation Plus
908 Starlight Loop
Twin Falls, Idaho 83301
[email protected]
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Well, after a read, I have to say that is surprising but great news - very welcome ! Good to see you back on deck Bill ! :t:

Sounds like an interesting venture, and I'm glad you're back obviously up to tackling it - great to know that 'old' bins will be salvaged and sent back into the market properly collimated.

I hope we get to see some of the transformations - either on a website, or thread here. Personally, I also hope you'll be able (and willing !) to take on an apprentice or class subject/project (if any of that fits in with your intentions and time :) to pass on even a fraction of your knowledge :)

I look forward to seeing what you come up with -
* locally crafted, custom feral animal perhaps? leather armouring and/or neck strap pads, or some such !
* various 'hot rodded' binoculars - maybe:
i) Swift Audubon 8.5x44 ED porros with the internals appropriately blackened and baffled up, perhaps some higher quality eyepiece bodies/rubbers, etc (some good photos of the unit I had showing the 'opportunities' available in the relevant thread on BF).
ii) Zen-Ray ED3 7,8,10x43 with the focus mechanism backlash/hysteresis fettled out of it. Perhaps also new armour options (shape is fine) - but after 10 years of sunscreen hands and 'Twisties' fingers, it goes a bit ordinary ! I couldn't recommend any other Zen models, but I think the ED3 might be a goer.
iii) other quality perhaps single coated lens bins - is it an option just to replace the objectives with a multicoated hi-spec ED set ? (just thinking out loud - don't make me walk the gang plank ! lol :)
iv) whatever other gems you will imagine .....

All the very best of good luck, good health, and happiness Bill :t:

Chosun :gh:
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That's great, someone with as much passion, knowledge and experience as Bill has for binoculars needs to stay involved in the field. Good luck!
Hi Bill,

I looked you up at Google streetview.
The Nissan crewcab is yours?

Bon voyage, sailor


Hi Jan,

My little truck, a Chevy Colorado, is not a crew cab. The car that only sits outside when I'm working in the garage is a Subaru. It works GREAT in the snow.

Look again, I'm at 908 Starlight Loop, Twin Falls, Idaho. :cat:

Cheers, buddy,

Hi Jan,

My little truck, a Chevy Colorado, is not a crew cab. The car that only sits outside when I'm working in the garage is a Subaru. It works GREAT in the snow.

Look again, I'm at 908 Starlight Loop, Twin Falls, Idaho. :cat:

Cheers, buddy,


Yep, I did and see a Nissan? outside with Titan written on the side and a person with a young 5 years? old girl in the doorway of that house (probably her car).

Yep, I did and see a Nissan? outside with Titan written on the side and a person with a young 5 years? old girl in the doorway of that house (probably her car).



Hi Jan,

I’ve found the photo to which you are alluding. I did not doubt that you knew what you saw, but we have been in the house for 5 years and realtors still have photos of it floating around Internet. The vacant field next to that Nissan has long held a home 2 ½ times the size of ours. And that tree in the front yard—that had a 5-inch base when that photo was taken—now has an 11-inch base as seen in my photo, attached.

We are a 10-minute walk from our chapel and a 10-12-minute drive from the temple, where we served for two years, and will again when Debbie retires.

Finally, here’s a photo of our Falls. It is not as wide as Niagara but is 43 feet deeper. :cat:




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Bill, one question.
We all read about 'cherry' specimens, optical gear that performs especially well.
Most people do not have the tools or even the eye to make the distinction, but once in the field, the difference shows. Some of that reflects production variances along with cost driven design choices.
When a qualified optician tunes a glass to best advantage, will the effect be material or is so much tied to the lenses and the mountings that the gains are minimal? If the latter, there is no opening there.
But if there is real benefit, I believe there are many buyers of even alpha grade optics who would pay to have their gear carefully optimized.
I don't want to speak out of turn, but I reached out to Bill due to this interview to see about fixing my Zen Ray Prime HD bino. He responded saying that he wasn't doing the business after all. He is busy with other things in his life and didn't see how to make this venture work without losing money. He referred me to Cory Suddarth and suggested that he would be able to help me. He apologized for taking a few days to get back with me and suggested that SOR would be a terrific choice.
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