Thu, Dec 21, 2017, 06:51 AM
Browsing the net, games, camera, apps etc., are increasing the use of smart phones. Notably, the camera has become the most wanted tool on the smart phone. Taking selfies, photos and videos and sharing them with friends on social media, has become a hobby. That is why, phones that have prominent camera features, are popular.
Selfie-craze has increased to a large extent in our country. That is why companies are coming out with latest models, highlighting the cameras. There are many things to learn about smart phone camera, that is so important. Normally, people think that a camera with more pixels is superb. It is wrong. Despite the number of pixels, if a picture has to be of good quality, there are other important features.
Several smart phone companies are highlighting camera pixels. They are advertising in bold letters about 18 mega pixels and 23 mega pixels. These figures look attractive. But nothing is revealed about the camera lens. Phone companies procure camera sensors and lens separately and fix them in the phone. When compared with the lens, camera sensors are very cheap. Because of this, the companies fix sensors with high resolution, to a low resolution lens, to save on costs. The quality of the pictures suffers, due to low resolution lens, despite high resolution camera. As a result, the resolution of the actual photo is less.
This is very essential in digital photography. It reveals the competence of the camera. It impacts the clarity of the picture. For example, let us say you are taking a picture of a park. It is useful only if every blade of grass, plants, leaves and flowers are absolutely clear. For this a good quality camera is needed.
Also, the number of pixels in a scene is mentioned in the resolution. The resolution of an image is equal to the multiple of its height and width. Supposing an image is 2,048 pixels wide and 1,536 pixels high. The multiple of these two is 31,45,728. We should understand that the picture has that many pixels. This is equal to 3.1 mega pixels. One mega pixel is equal to 10 lakh pixels. This image can also be described as taken in 2048x1536 resolution.
If the mega pixels are more, the image can be shot in a larger size. Pixel Per Inch (PPI) is the number of pixels in an inch. This is mentioned in the specifications of the screen of a smart phone. Mega pixel indicates the rating or quality of a picture. A room can easily accommodate 10 people. But if 50 or 100 more barge in, they would be suffocated. Similarly, if more mega pixels are fixed close to each other on a camera sensor, the quality of the picture is affected. That is why pictures taken with a budget phone camera are blurred. That is why experts look for lens and sensors, rather than megapixels.
The most important factor in a lens, is its diameter. If all other aspects of the lens are intact but the diameter is small, it affects the image. Diameter of the lens can limit the scope of resolution. The amount of light the lens can gather depends on its diameter. If the lens is big and has high resolution, it gathers more light. Digital cameras have lens that are 10 mm to 50 mm wide. Still wider lens too are available. Smart phone camera lens are small. These are just 2 mm diameter. Despite this lack, smart phone camera sensors have high resolution. For example, you imagine that with a 20 mega pixel phone camera, you can take a very clear picture. But for this, just the number of mega pixels is not sufficient. The diameter of the lens should be big.
The camera aperture too is an important part. Its importance has grown in present day smart phones. In most phones, aperture f 2.2 or f 1.8 are present. Aperture number plays a key role in quality of the picture. It is well known that photography is based entirely on light. Based on how much light a camera captures, you can estimate its quality. In smart phone cameras the lens and sensors are small. They capture less light. This affects the final picture. Camera quality is gauged by how much light is reaching the pixels, through the lens. Apertures determine this factor.
Aperture is a tool that determines the amount of light that enters the camera. This is measured by f stops. The smaller the f stop, the bigger the aperture. The light reaching the camera sensors in more. Photos taken in this manner are of better quality, with less blurs and no unclear images. The aperture of the camera should be big. View the image on the side for understanding this. If f stop is low the camera sensors can get more light. The time of the shutter speed is slowed down, leading to clear image, without blurs. If the aperture is big, less number of pixels will not make a difference for a clear image. However, photos are not of good quality, when taken with low aperture and low pixel count. Most of the smart phone camera apertures are fixed (wide and allowing more light to enter.) The light has to enter only through the lens. As the f stop number keeps reducing the aperture area keeps increasing. Subsequently, the amount of light passing through the lens into the camera will increase.
Why photos of moving objects are not clear?
Many might have observed that shooting a fast moving object is tough and the image is not clear. That is because Complementary Metal-oxide Semiconductor (CMOS) sensors are being used in phone cameras. These sensors capture the pictures one line after another. But expensive Charge Coupled-Device (CCD) image sensors capture the whole picture at one time. Still images appear the same in both the sensors.
Those who wish to take good pictures, should surely check out IOS option in camera settings. This determines the camera sensitivity. Photo quality is reduced when the lighting is less or when clouds hover and the environment turns dark. For example, when you take a picture while cycling, the image is blur. But if you change to auto mode in IOS option in camera settings, and then take a picture, it is different. The IOS should be switched off after clicking and before viewing the picture. You can notice the difference. If IOS is low, more light is necessary. The shutter speed has to be reduced. Normally, in good light, shutter speed is set at 100 to 200. But if more light is not needed and shutter speed has to be slowed down, reduce the IOS.
This is also called exposure time. It aids in capturing the light by opening the shutter. For example, you see Dolphins diving in the sea at great speed. For shooting this, the shutter speed has to be high. If it is low, the picture is blurred.