Our Services:


Lens Polishing and Re-coating
Lens Cement Seperation Repairs
Fungus and Haze Removal
Camera Body Repairs
Service Disclaimer
Focal Point Inc.





Lens Polishing and Re-coating


This procedure is usually too expensive for generic type lenses or entire lens systems, and is really intended only as a repair. There are also certain apochromatic glass and ED glass that may be too risky for this procedure because of their sensitivity to heat. We have had success with this glass, but the risk of breakage increases from about 1% to about 50%.

Some people have been told there is no way to remove scratches from the lens without ruining the performance of the lens system. Although it is possible to ruin a good lens system if you have no expertise in the process, we only remove coating and never enough glass material to change the formula. If a scratch is deep enough to feel with your fingernail, then it is probably too deep to repair. Another way to tell if the glass is damaged beyond repair is with a 5 to 10 power loupe, look at the scratch and see if there is fracturing under the surface. If there is fracturing under the scratched surface, we would need to remove enough glass material to get to the bottom of the fracture, and that would possibly change the radius curve and render that lens useless.

Some lenses like the early Zeiss Planars have cemented doublets for their front elements. A cemented doublet should never be put into a coating chamber due to the problems it can cause. The 200 degree temperature will cause cement failure, leading to breakage or contamination.


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Lens Cement Separation Repairs


Lens cement separation repair is also labor intensive, mostly in separating of the two or three glass element. This is done with heat, but very slowly as to reduce any risk of thermal fracturing. Then these elements are recemented with optical grade copolymer cement, centered, and cured. We use various tools to center the elements for optimum performance.

Some elements and or doublets are machined into their mounts meaning that instead of a threaded retaining ring being screwed down on the element, there is a thin wall of metal left above the glass edge and the mount with glass is returned to the lathe, and the thin wall is burnished over the glass. This style is more expensive to remove and in rare cases must be cut from its mount.


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Fungus and Haze Removal


Fungus can be a real problem, and even though we have several ways to remove the damage, some are not economical. What you see is not the fungus but what the fungus left behind. It usually looks like a cotton seed or spider web and may even take on some very unusual patterns. The appearance can be due to corrosion, staining, or even a destructive etching. The fungus arrives in your lens with moisture in the form of condensation, and as it lives in this environment, it secretes hydroflouric acid. This starts the corrosive action that can form on the surface. It attacks the coating or the glass and may etch it beyond repair. We need to perform a test to know if it will clean up without extensive polishing and recoating.

Haze is a different problem with certain lenses and usually can be cleaned out without a lot of expense.


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Camera Body Repairs


Sorry! We no longer repair camera bodies!


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Service Disclaimer


Most of these optical repair operations are not without risk of breakage because heat is involved. There is no way to know what flaws may be lurking in any particular piece of glass. In the vacuum chamber, the environment is heated to 200 degrees centigrade. This is to insure good bond between the glass and the coating. The glass is also heated during the setup for polishing. In manufacturing there are always extra elements made because of the possibility of breakage during grinding, lapping, or polishing and also vacuum deposition coating. The glass is also heated in the decementing process for cement separation repair procedure. Although we take every possible care in the handling of these elements, there is on occasion breakage with no visible reason, and therefore the risk is the customers.


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