Exploring the Revolutionary Impact of 4K Photography in Imaging
Oct 25 2018
Humans are visually oriented creatures, and the pursuit of the ultimate sensory experience through optical imagery has never ceased. The development of digital imaging and optical technology has made significant strides in the past two decades. A few years ago, when Full HD quality was gradually becoming the mainstream resolution for videos, the higher-pixel 4K resolution (4K resolution) was introduced soon after.
Although 4K imagery hasn't yet dominated the image market, its application shows a growing trend. Devices supporting 4K photography, digital cameras, peripheral players, monitors, and even 4K film and television works are becoming increasingly common. Many passionate amateur photographers have already adopted 4K video equipment for shooting video logs (Vlogs), not to mention professional media production companies and film producers who strive to be at the forefront of imaging technology. So, where does the charm of 4K imagery lie, and what changes can it bring to video production? Let’s explore further.
We know that to see clear image details at close range, the pixel density in the image needs to be denser. 4K resolution refers to a resolution of 4096 × 2160px (note 1), with the horizontal resolution having 4,000 pixels, hence the name 4K resolution. Compared to Full HD's resolution of 1920 x 1080px, 4K imagery has four times the total pixel count. The richer image detail information in 4K images brings objects in the picture closer to the real visual atmosphere.
The popularity of 4K high-definition videos is not just due to "clear images." The detailed textures in these shots, like hair on a person's body, facial spots or wrinkles, the gloss of wildlife fur, the night sky with stars and galaxies, splashing droplets, mist, and debris and smoke in explosion scenes, can more effectively stir viewers' emotions. This is the biggest charm of 4K imagery!
Note 1: The specification for 4K movies (Digital Cinema Initiative; DCI) is 4096 x 2160px, while the specification for 4K TVs is 3840 x 2160px.
(4K pixels are four times that of FHD pixels.)
(Comparison of 4K and FHD quality after enlarging a section of the image.)
(4K high-definition is best suited for presenting exquisite images.)
The contribution of 4K films to the imaging industry is not just about sharp image rendition; it has also changed the way photographers work. In the past, shooting videos and static images were separate tasks. To capture the most exciting moments or expressions, still photographers had to rely on high-speed continuous shooting. Although top-tier DSLR cameras from Canon and Nikon can reach 7~14 frames per second, and advanced mirrorless cameras from Sony and Fujifilm are similar, if the camera's continuous shooting speed is not fast enough or the timing of the shutter press is off, the most exciting moment might be missed. Even the top-tier cameras' continuous shooting speeds may not always capture these dynamic moments, let alone mid-range and entry-level DSLRs with speeds of no more than 6 frames per second.
A video is composed of at least 24 static images per second, i.e., a frame rate of 24 fps (frames per second) (note 2). Based on this principle, image creators can extract a static image from a video for flat editing. The higher the frame rate, the more static frames per second, meaning smoother video playback. For photographers in fields like ecology, portraiture, weddings, etc., a high frame rate greatly increases their chances of capturing the perfect moment. Imagine extracting at least 24 static images from one second of video; this is a continuous shooting speed unattainable by regular cameras.
The high quality of 4K allows extracted static images to have over 8 million pixels, more than four times that of Full HD. Some might think 8 million pixels fall short compared to modern DSLR cameras with 20 million pixels or more, but for most users viewing images on computers, phones, or tablets, 8 million pixels are more than sufficient. This is even suitable for printing magazine covers, making magazine spreads, and graphic illustrations – achievements that were difficult for Full HD quality.
Note 2: The human eye can distinguish 24 images per second. When image playback exceeds 24 frames per second (24 fps), the visual persistence effect creates a continuous animatio
(Extracting static frames from a motion video can increase the success rate of capturing high-speed moments.)
Users of digital cameras know this: the higher the original image's pixels, the clearer the image remains when enlarging a part of the picture. Similarly, high-quality film materials give producers more flexibility in post-production editing. Film editors can crop parts of a 4K film during post-production, allowing for better composition or close-up effects, thus conveying a superior visual effect. However, the ingenious use of 4K high quality doesn’t stop here; with a bit of creativity, there are many more innovative applications for 4K photography.
Traditionally, multi-camera operations required at least two cameras to give the director multiple angles for switching views. But have you ever imagined achieving a multi-camera effect with just one camera? By utilizing the advantages of 4K high-quality images, image creators can split a single 4K resolution image into four Full HD 1080p quality images using a 4K image processor. This not only provides more diverse viewing angles but also maintains a certain level of picture quality after splitting. Imagine a three-person band performance captured by one 4K camera and one 4K image processor, achieving four-camera positioning and high-quality output, with full, medium, and close-up shots, and the flexibility to adjust and reframe at any time. Such professional shooting and image switching operations can be easily managed by one person, significantly reducing the manpower and equipment needs of traditional multi-camera operations.
The application of 4K high-quality photography is not just about pursuing visual "thrills." From a practical application perspective, 4K image processors have expanded 4K image applications from the broadcasting field to education, training courses, multi-camera interviews, self-media broadcasting, live events, and even environmental and safety monitoring. In the near future, 4K image applications are expected to become more prevalent in our lives.
(4K imagery can be split into multiple frames, achieving the effect of multi-camera shooting.)
