There are mold spots on the lens of SONYD DSC-W290 digital camera. How to deal with the mold spots?

There are many shapes of mildew, the most common ones are as follows: (A) Shape like a dead branch - the traces are very clear, the main branch is divided into long and short branches, and the color is white. This bacteria is easy to wipe away. (B) Shape like a flower - the main branch is very clear, the branches are longer, the edges of the branches are blooming, and the color is blue. The main branches appear silvery when reflecting light, and are mostly attached to the blue film and lenses in front of the aperture leaves. They are easily erased in the early stages. (C) Like the shape of a jellyfish, the branches extend from the main body to all directions, and the center is densely covered. It is easy to erase when it first turns white. (D) A mountain that looks like a map. The main branches grow in unequal shapes, and the sides of the branches bloom. They are lighter and white in color. When you see this, you should wipe it off immediately because it grows very quickly. If it stays for too long, it will invade the film layer and be difficult to remove. (E) Like spots on the cortex. It forms a zigzag shape and is very finely distributed on the lens. The edges are melted and the color is light and white. This fungus spreads quite quickly and should be rechecked immediately. Let it continue for two or three months before it grows into the film and cannot be removed. Any form of mold should be cleaned up as soon as it is discovered, if it has been around for too long. It will leave traces or not be removed at all. Severe mold will reduce the image difference and reduce the transparency of the lens, but it will not affect the clarity of the lines.

(2) If there are strip-like scratches on the lens, the main cause is that hard fine sand is attached to the mirror surface, and the lens is wiped without blowing it off, causing the hard sand dust to rub against the mirror, or the lens is wiped with The object is too hard and you use too much force when wiping. The film on some lenses is soft and thin and can easily cause scratches. These scratches damage the transparency of the lens and can cause reflection and scattering, affecting contrast. If there are serious scratches in the middle of the lens, blurry images will occur when shooting with a narrow aperture.

(3) If there are bubbles in the lens, the best way to observe the bubbles is to use the above-mentioned observation method (3). If you see small black dots in the shape of a circle, they are small bubbles. There are small bubbles in the middle of the black circle. The luminous spots in the white garden are larger bubbles, which are formed because the gas expelled from the glass before solidification failed to rise to the surface of the solution in time. Fortunately, modern lenses rarely have bubbles. In theory, they can cause reflection and refraction of light, but in practice, their harm is no more serious than dust of the same size. However, when purchasing, it is better to have no bubbles. .

(4) There are rust powder or small black fragments inside the lens - rust powder is the oxide that falls off due to the rust of the aperture system, and the black fragments are the corrosion of the black paint on the inner edge of the lens barrel. Most of the things that fall off fall on the lenses before and after the aperture and must be removed, especially near the center of the lens. This is because they will block light from entering the camera's film. For example, if the center of the lens is condensed a lot, it will lead to underexposure and unclear images when shooting at a narrow aperture.

(5) If the lens is foggy, you need to use the (3) method to observe the problem. It is easy to find. Most of them occur on the lens before and after the aperture blade, and it adheres to the lens like smoke. Some are caused by the bonding between two lenses. The causes are mostly the evaporation of grease, acidic gases, long-term exposure to strong light, air humidity, etc. At the same time, optical glass containing silicate and boric acid has hygroscopic properties, and is added The membrane layer is not a tight layer without pores. If water vapor condenses in the pores, mist will also form. This problem should be eliminated as soon as possible. It cannot be eliminated after a long time. The impact on the image is to greatly reduce the contrast beyond normal. This problem mostly occurs on lenses used for magnification.

(6) The lens is deglued. In the past, most lenses were bonded using Canadian resin and the lens after being heated. In modern times, Aradite's artificial resin resin is often used. It does not require heating and can bond glass in a cold state. It has high strength in the hardened state and is compatible with water. , gasoline, acetone and methanol have no dissolving effect. Use the second method mentioned above to inspect the degumming. The shape of the degumming is the same, mostly showing a halo (the reflected light is silver like C, or cracked). The reason for degumming is caused by the tension caused by cold shrinkage and thermal expansion. In general, sol is mostly used in tropical zones, and degumming is used in cold or subtropical zones. To treat degumming, the lens must be heated until the glue deepens, and then the lens is separated. However, this can easily cause cracking due to excessive temperature changes, which is very dangerous. Moreover, when bonding, you must use lens adhesive with the same refractive index as the two pieces of glass. Otherwise, it will affect the quality of the lens. If the lens has poor refraction, if the problem is on the edge of the mirror, you can narrow the aperture to reduce the problem. its undesirable effects.

(7) Sometimes, shake the lens slightly. If you hear the sound of glass colliding, the lens is loose. The reason is that the ring holding the lens is not tightly closed, or the lens has been collided and the screws have become loose. If the lens is loose, etc., this problem should be repaired immediately. Because the lens elements are loose, the elements are not parallel to each other and the main axis cannot be in a straight line, causing inconcentration aberration and destroying the clarity and sharpness of the image. Unable to obtain clear negatives.

(8) The lens has fingerprints or oil stains that cannot be wiped off - this is because oily things or fingers come into contact with the surface of the lens, and if left alone for a long time, the acidic corrosion of the oil will cause the film to be added. If it is too deep and can no longer be removed, it will have an impact on the transmittance of the lens.

(9) Very fine holes suddenly appeared in the lens, commonly known as "bean skin holes". When the lens is corroded by the volatilization of chemical gases, grease, water vapor, etc. for a long time, it mostly occurs on lenses with severe fogging. This will also happen if it is wetted by chemical liquids, such as boiling water.

It is easy to observe with the help of a magnifying glass. This problem will affect the clarity of photographic lines. When the aperture is closed, the image will also be scattered.

(10) If there is a small patch of blue on the lens, it is caused by the evaporation of grease condensing on the lens. This evaporation is blue and is easy to wipe off. When wiping, it will be obvious that it is oil stains. substance.

(11) The film on the lens has peeled off - if this hair was not seen before, the ancients had to use the second observation method. If there are areas where the film has peeled off, the reflection is particularly strong. Most of them are caused by the film on the lens itself. It is soft and thin. If you apply a little force on the lens, it will fall off. This problem will damage the coating, increase the reflected light, and weaken the image contrast.

(12) Finally, there is condensation of water vapor on the lens because the clarity is cold and hot, the glass is cold, and the moisture in the air condenses on the glass. Just put the lens in a ventilated place and blow it for a while and it will disappear. However, do not store the camera before the moisture disappears. This will cause the lens to become moldy. If you take photos when moisture is present, the image will be blurry and blurry. Scattered light occurs at the light level.

To protect the lens, you should pay attention to prevent collisions, avoid placing it in high temperature places, avoid being close to chemical liquids and smells, avoid being exposed to strong light for a long time, do not add oil to the aperture blade system, and avoid being contaminated by sea water or water. , avoid trying to disassemble the lens yourself. When the lens is not in use, a lens cap should be attached to prevent dust. After use, the lens and camera should be wiped clean of oily hands and juice. If the lens is broken, it should be repaired as soon as possible.

Another transfer:

Use a piece of lens cleaning paper dipped in 3% hydrogen peroxide. Use a larger amount and gently rub it over the surface of the lens. Just make sure the hydrogen peroxide sticks to the lens. . If the lens is too moldy, simply soak it entirely in hydrogen peroxide. After a short while (30 seconds is enough), use lens cleaning paper dipped in absolute alcohol to wipe it gently. The purpose is to use the absolute alcohol to absorb the moisture on the lens and wash away the fat-soluble dirt on the lens. After the above treatment, as long as the mold has not eaten too much of the glass, your lens will be like new. The lens that was processed 3 years ago is still as clean as new.