Friends who use DSLR/EVIL all know that it is the greatest pain in your heart to change lenses carefully when you are outdoors. Dust is like a spirit behind your back. It is contaminated with light-sensitive elements from time to time, making the dust spots of every photo the greatest pain in your heart. But how do we judge if the camera is dusty? Now as long as you press a command button easily under Photoshop, where the dust spots on the photosensitive components are immediately exposed oh! ____________
The problem of camera dust, when you buy a single eye or a slight single eye, will follow you like a shadow. Sometimes, simply changing the lens, using zoom lens to take pictures in windy and sandy areas, etc., all have ways to "inhale" dust particles into the lens, and then as the camera is operated, the dust runs into the sensor. Although the teachers teach, when changing the lens outdoors, as far as possible in the current environment, choose the place where there is shelter, and pay attention to the action of removing the lens, the fuselage clamp down, but the "dust" is a nuisance, there is a way to stick on the photosensitive elements.
_If the camera does not have built-in supersonic dust removal function, it is necessary to sometimes be concerned about whether the photosensitive element has entered the dust problem. (Image source: digital-photography)
_When replacing the lens, remember to remove the camera ring downward to replace the action, can slightly reduce the risk of dust.
How to Find Dust Entry
What's more annoying is that when we take photos under a large aperture (e.g. F1.8), we seldom find dust spots in the photos (unless the dust is really big and the nose droppings can be seen with the naked eye); but when we take photos with F8 or smaller apertures, these dust spots are like evil spirits that are illuminated by a phantom, one by one. On the film, some are not even obvious.
So check whether there is any way to dust the sensor, quite a lot of people in the purchase of cameras, have heard the shopkeeper said: "Reduce the aperture to F22 and reduce the ISO, the white wall or white paper photography, you can see where the dust. But is there a simpler way to detect it? Can I know precisely and quickly where there is dust in the sensor?
The method is quite simple, as long as you take out recent photographs, try to pick out daytime photographs and select a few more, throw them into Photoshop and press Ctrl+I, let the photos enter negative mode, you can immediately see the dust entry point which is difficult to detect by the naked eye. At this point, you can start with the camera settings, turn on the settings for retracting the reflector, and put the fuselage ring downward, let the air blow inward, try to see if you can blow down the dust entry point. If these evil spirits are quite stubborn, they can not be thrown away like nose droppings, and then consider whether they should be sent back to the original factory for cleaning up.
_Take this picture as an example, we can find one problem on the left and about six problems on the right. But what if we drop this photo into Photoshop and switch it to "negative mode"? (Image source: digital-photography & nbsp;)
_Change into a negative photo mode, you can find more dirty spots hidden in the dark that are not easy to find have emerged. (Image source: digital-photography & nbsp;)