Camera Basics
A photographer’s exposure is determined by altering the settings on a DSLR, and determines how exposed the image will appear.
A camera is essentially a light-tight box incorporating a lens, a shutter and an aperture. It also holds a viewing system, through which you can create the image. The lens forms an inverted image of the subject inside the camera, and adjustable lenses have a focusing control enabling you to sharpen the image by altering the distance. This allows you to take sharp images at a variety of subject distances. Shutter speed, ISO and aperture are adjustable, so that you can vary the duration and brightness of light in the image that you are creating.
Shutter speed
Shutter speed is a relatively simple concept to comprehend. It essentially controls precisely just how long the sensor inside the camera is exposed to the light and how long the shutter remains open depends on how much light there is, which helps to restrain the under/over exposure of images. You can also increase the shutter speed to freeze an action, or increase aperture for selective focus.Essentially it is a measure of the amount of time the shutter opens to allow the flow of light onto the imaging sensor. From an artistic point of view shutter speed is used to depict your subject in its motion.It is often used to minimize the chance of camera shake, which often ruins a potentially great shot.
Shutter speed is a relatively simple concept to comprehend. It essentially controls precisely just how long the sensor inside the camera is exposed to the light and how long the shutter remains open depends on how much light there is, which helps to restrain the under/over exposure of images. You can also increase the shutter speed to freeze an action, or increase aperture for selective focus.Essentially it is a measure of the amount of time the shutter opens to allow the flow of light onto the imaging sensor. From an artistic point of view shutter speed is used to depict your subject in its motion.It is often used to minimize the chance of camera shake, which often ruins a potentially great shot.
Shutter speed
Shutter speed is a relatively simple concept to comprehend. It essentially controls precisely just how long the sensor inside the camera is exposed to the light and how long the shutter remains open depends on how much light there is, which helps to restrain the under/over exposure of images. You can also increase the shutter speed to freeze an action, or increase aperture for selective focus.Essentially it is a measure of the amount of time the shutter opens to allow the flow of light onto the imaging sensor. From an artistic point of view shutter speed is used to depict your subject in its motion.It is often used to minimize the chance of camera shake, which often ruins a potentially great shot.
Shutter speed is a relatively simple concept to comprehend. It essentially controls precisely just how long the sensor inside the camera is exposed to the light and how long the shutter remains open depends on how much light there is, which helps to restrain the under/over exposure of images. You can also increase the shutter speed to freeze an action, or increase aperture for selective focus.Essentially it is a measure of the amount of time the shutter opens to allow the flow of light onto the imaging sensor. From an artistic point of view shutter speed is used to depict your subject in its motion.It is often used to minimize the chance of camera shake, which often ruins a potentially great shot.
Using manual settings will allow you to control correct exposure that you desire. The number is usually a fraction, so if you see a shutter speed of 4000, it’s actually 1/4000th of a second, while a value of 200, is 1/200th of a second.
Aperture
Aperture has comparable features of that of an eye. The eye has an iris that regulates the amount of light that the brain will fundamentally interpret. If you were in a badly lite room, the pupil will convert bigger and gather more light, but on a very sunny day, the pupils need to be reduced to avoid the entrance of extra unwanted light. The same goes for a camera; there is a mechanism that controls the amount of light reaching the sensor. But your eyes don’t work exactly like a DSLR, as inside the camera will be a combination of parameters to expose the image correctly.
The lens aperture is specified as an f-number, the smaller the f number (f/1.2,f/1.4) the bigger the aperture is and the more light that is allowed to pass through. If the f stop is higher (f/16,f22) the smaller the aperture size.
A common aperture range may be f/2.8 at the widest aperture and f/22 being the minimum, but these can differ between lenses.
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This photograph benefits me to understand and extend my knowledge of the technical side of aperture. ISO-International standards organisation The ISO denotes how sensitive the image sensor is to the amount of light present. The higher the ISO, the more sensitive the image sensor is and therefore has a higher chance of capturing the desired appearance of the image in low light situations, although using higher values dramatically increase camera noise.The relationship between the settings allows you to produce a variety of affects to your desired outcome. Aperture and shutter speed are bound together, if you open the aperture you increase the shutter speed, and if you close down the aperture you decrease the shutter speed. |
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Shutter Speed 1/25 sec F Stop f/5.0 ISO 200
 P)- Programmed auto In this mode, the camera automatically adjusts shutter speed and aperture for optimal exposure in most situations. This mode is recommended for snapshots and other situations in which you want to leave the camera in charge of shutter and aperture. (S)- Shutter-priority auto In shutter-priority auto, you choose the shutter speed while the camera automatically selects the aperture that will produce ideal exposure. (A)- Aperture-priority Auto In aperture-priority auto, you choose the aperture to control depth of field, while the camera automatically selects the shutter speed that will produce optimum exposure (M) In manual exposure mode, you control both shutter speed and aperture to your creative intent. Scene Modes-Selecting a scene mode automatically optimizes settings to suit the selected scene, making creative photography as simple as rotating the mode dial. Portrait – Use for portraits with soft, natural looking skin tones. Landscape-Use for vivid landscape shots in daylight or at night. Close up- Take vivid close-ups of flowers, insects and other small objects. Sports-Freeze motion for dynamic sports shots Night portrait-shoot portraits against a dimly lit backdrop There is also a function on most DSLR’s called Bulb. Bulb mode allows you to take an image with an exposure longer than 30 seconds and for however long you desire. I think this setting is great and allows you to experiment and be creative with you images. I created the following image whilst using the bulb setting.  File Formats When a camera captures an image it has to be saved or memorized in a “file format”. If the binary material is seen as the communication, the file or format can be equated to the language from this communication. The information can only be read and comprehended if the software distinguishes the format. Images can be accumulated in numerous different formats. The four most domineering formats in most widespread usage are: · RAW (.dng)- Camera RAW or Digital negative · JPEG (.jpg, jpf and jpx) –Joint photographic Experts Group · TIFF (.tif)- Tagged Image File Format · Photoshop (.psd)- Photoshop document RAW or Digital Negative-Distinct from other file formats, RAW is not an acronym for a much longer name. Selecting the RAW format in the camera instead of JPEG OR TIFF prevents the camera from administering the colour data gathered from the sensor. The RAW data is what the image established before the camera processes the image. The unrefined RAW has to be converted into a usable image file format using image editing software. JPEG (Joint Photographic Experts Group)- Industry Standard for compressing incessant tone photographic images directed for the Internet or for storage when space is restricted. JPEG compression uses a “lossy compression”(image data and quality are forfeited for minor file sizes when the image files are closed. The consumer is able to restraint the amount of compression. A high level of compression results in a higher quality image and a smaller file size. A low level of compression results in a higher quality image but a larger file size. It is favorably recommended that you only use the JPEG file format after you have fulfilled image editing and always keep a master document for archival purposes. On my Nikon d90, although it is everyday practice on most cameras in todays world, manufactures offer a RAW+JPEG option which I consider offers the best of both worlds, intending that the image is captured in both RAW and JPEG formats. Even though this consumes additional storage space, it means that a digital image is detained for archival intentions or to be used at a later stage, but a previously processed JPEG version is available for use. The JPEG is also accessible for sharper preview of the image, as the RAW file is often only available after opening. PDS (Photoshop Document) – This is the default format used by the Adobe image editing software. A photoshop document is usually kept as the master file from which all other files are created depending on the obligations of the output device. TIFF (Tagged Image File Format)-This has been the industry standard for images directed for publishing in magazines, books etc. TIFF uses a “lossless” compression (no loss of image data and quality), although conserving the quality of the image. It is only capable of compressing images by a small amount. Understanding Resolution The foundation of every D-SLR is the image sensor, the minute component that translates the real world into digital form. The sensor is a wafer-thin array, which is contained of million little light-sensitive photo indicators, positioned in a consistent grid system. These are commonly referred to as Pixels. Pixels are rectangular and are situated in rows horizontally and vertically to form and materialise a grid or mosaic. Every pixel in the grid is the same size and is consistent in colour and brightness,i.e. the pixel does not differ from one side of the pixel to the other. If we abundantly zoom into an image, you can appreciate how smooth and soft flowing shapes can be captivatingly composed out of rectangular building blocks, with not a curved pixel in sight. The greatest substantial way to portray a smooth flowing line is to present the pixels so small that we cannot make them out to be square using the naked eye. The following images show an original image with typical image pixilation once closely zoomed and magnified. |
An Introduction to Lenses
A camera’s lens redirects light rays coming from the subject so they establish an image onto the sensor. A lens is made up of one of more glass components, that can either have a converging or straying result on the light rays. Convex elements generate a inadequate image on their own, and lens manufacturers reimburse for this by incorporating weaker concave elements. These additional elements advance the image quality but also increase the price of the lens.
A typical standard lens gives you an angle of view that is roughly the same as normal human vision. The natural perception gives the standard lens the greatest widespread versatile approach for general photography.
Wide-angle lenses have characteristically a wide angle of view. They capture the setting in front of you, to the side of you above and almost behind you, so there superb for taking images of a vast widespread landscape. They make objects appear further away than they actually are.
Telephoto lenses let you home in on distant objects; they also make perspective objects less obvious so portraits are more flattering. You could also use a telephoto lens to isolate interesting details from a scene .
Macro photography is a term used for close up images. It is a term related to most close up images but should really only be associated to images that have a 1:1 or closer magnification.
There are numerous methods to accomplish an appropriate magnification for close up images. The idyllic solution is an SLR or DSLR with a dedicated macro lens. This lens will have the 1:1 facility built in and the lens will be a suitable quality considered for this intention. An alternative option to a dedicated macro lens is to use extension tubes. These go between the camera body and the lens on an SLR or DSLR, they don’t have any glass in them, but they allow you to focus a lot closer than the standard lens would naturally.
Below is an image I have captured using a Macro lens. This is a technically incorrect image as the ratio isn't 1:1.
Depth of Field
Depth of field is the space concerning the nearest and farthest parts of a subject that can be recognised as a photographic image with modestly sharp details at one focus setting of the lens.
The widest aperture (smallest f number) gives the least depth of field while the smallest aperture gives the greatest depth of field.