Resolution in digital photography refers to the number of individual pixels (discrete building blocks or elements of a Photograph) that are used to define the detail in the photograph. Think of pixels as tiny, solid-colour square tiles in a very large mosaic floor or wall. Image size is defined by pixel dimensions, as in 1920×1080, which refers to the number of horizontal (1920) and vertical (1080) pixels in the matrix that constitutes the whole image. The higher the image resolution, the clearer and more detailed the photograph appears. An image with a higher resolution or higher number of pixels will print larger at the same resolution.
Inside your digital camera are specialised light-sensitive chips, called image sensors. Image sensors use either CCD (Charge-Coupled Device) technology or CMOS (Complementary Metal Oxide Semiconductor). (Ironically, only the newest and highest definition or the cheapest and lowest definition cameras currently use CMOS technology.) These chips are made up of arrays of image sensors. Each sensor translates the light falling on it into electronic signals, which define intensity and colour. This information is stored as digital data in a computer data device that’s built into the camera or as flash memory on a removable card. The data on these cards is translated by computer programs and displayed as colour pixels on the camera’s LCD or on a computer screen when shooting tethered or when transferred.
As you know that every camera, SLR or compact, comes with a pixel rating, such as 21 megapixels (million pixels) or 32 megapixels or up to 50 megapixels in the latest models. Medium formats have still higher megapixels in hundreds. More megapixels translate to more individual light sensors on the image chip or more number of individual building blocks, which translates to higher image definition, resulting in sharper and clearer pictures. Your camera’s megapixel rating determines how much detail can be captured in the highest or a specific resolution setting. You can usually blow up standard 35mm film to 8×10, 10×15, and in some cases 16×24 without seeing too much loss in quality, but go any further and the quality starts to degrade. There is a certain extent upto which 35 mm film can be enlarged. A medium format film (120mm) can give much bigger enlargements as the size of the film is bigger ( 6 cm x 7 cm ) When fine detail and enlargement are of prime importance, a large format camera was the ideal choice.
With digital cameras, the resolution of the image sensor determines the detail, so if you want the ability to blow up your pictures to any great degree, you will need to use a higher resolution camera and use the highest resolution possible on that camera. In early 2000s Digital cameras in the range of 6-8 megapixel were the first ones to produce images with quality similar to that of 35mm film. Popularly priced compact 2-megapixel digital cameras allowed for passable inkjet or photographic prints of up to 8×10 in size, comparable to machine-made prints available from consumer-level one-hour photo labs. with passage of time and improvement in technology standards continued to rise and today in 2016 we are talking of megapixels in 20s and 50s and general standards. What seemed fine at that time looks quite out of focus today. Also because there has been a rise in the standards of printers and well as monitors. resolutions have increased in these as well.
On the other hand, if your image is targeted for online display, such as the Web, video, or animation, the need for resolution will be much lower but its is still advisable to shoot at a higher resolution to get best possible detail. For web, shooting on a medium format camera may be an overkill and anything beyond 18 or 21 megapixel may not be desired. Eventually it will be reduced to the web size but its not just about the pixels but also about the quality of pixels.
The best advice is to buy the highest capacity memory cards you can afford and shoot all your pictures at the highest resolution you camera will allow. You may think you have a good reason to shoot at a lower resolution, but the only really good reason is if you just have no other way to get the shots you want to take without running out of memory before you can download the images off the memory card and start over. After all, it’s always better to have some picture of something that’s important to you than no picture at all. It’s equally important to remember that if detail and quality don’t exist in the image you shoot, you are never going to be able to restore or bring it back anytime later. Remember that you can never take exactly the same picture twice. (Well, almost never. Still-life photos taken under controlled studio lighting conditions are the one exception but still you may not be able to set up and light it up exactly the same way)
Importance of Resolution ?
The more resolution (pixels) your camera can capture, the finer the detail in the photograph and the more information you have to work with later in editing or printing the image. Due to the rapid advancements in digital technology, today’s digital cameras are approaching the quality of conventional film—and may soon surpass it. Higher resolution means sharper and more detailed pictures.
The resolution ultimately affects output (this applies to printers, film recorders, video, or the Web). Every type of output demands a certain amount of information from the images that it uses for input (the image stored on the memory card in pixels). Prints and slides demand a significantly larger number of pixels (about 240 to the printed inch) to produce good quality. Video and the Web require much less (between 72 pixels and 96 pixels to the displayed inch).
Cropping a part of a photo throws away pixels and, therefore, affects resolution. You can’t replace that resolution if you then enlarge the cropped image. Understanding what your target output is going to be will help you choose the appropriate resolution settings and help you learn how to frame your image to maximize results. However, as I mentioned earlier, the simplest way to deal with this is to capture every image with as much resolution as your camera can accommodate.
How to Adjust Resolution?
Most cameras provide multiple resolution settings. You can access the menu for selecting the resolution options through your LCD menu options panel. The exact pixel dimensions of each resolution setting will vary according to the megapixel rating of the camera. It is a very good idea to keep the camera set at its highest quality, highest resolution setting until you have a critical need to capture more pictures than that setting will allow. Remember, once you’ve taken the picture, you can never increase its quality. Nor can you retake the picture.
It’s a good idea to check your camera’s control panel after you change resolution settings to see how many shots you can store on your memory card. This will allow you to gauge your shoot.