This year, prospective buyers of digital cameras will feel happy and they are pampered by the manufacturer of the advanced camera because the camera almost all made in 2010-2011 already have the ability to record High Definition resolution video (HD). Somewhat different from past years when HD video is still a fancy features only found on expensive cameras only. Now when HD video is so common, if you already understand the ins and outs of this one feature? If not, hopefully this article helps.
sanyo-XACTI
HD video on a digital camera is a new round of photos and video convergence cameras. First, the camera can record video images of nature is only for a short clip that quality is far from adequate. Even if you had said yes to wear a camcorder to record video instead of camera images. But with increasing evolution of digital cameras, even on a DSLR, as well as technology gets better processor inside the camera, it features high-resolution video more easily implemented in digital cameras. When you have this, do we still need a camcorder again?
Pros and weakness of HD video
Unlike the format of SD (Standard Definition) that we usually see on a conventional TV (who wore the aspect ratio of 4 by 3), HD video has an aspect ratio of 16 versus 9 or widescreen format. There are two kinds of HD format offered by camera manufacturers, namely HD 720 (1280 x 720 pixels) and HD 1080 (1920 x 1080 pixels). Both of these HD video formats already meet the standards for broadcast video quality, when viewed from the resolution. In industrial video discs, HD video standard used in Blu-ray chip with a capacity of 25 GB per kepingnya. The sharpness and details well above the SD format with VGA resolution (640 x 480 pixels) let alone a QVGA (320 x 240 pixels). VGA format itself almost close to the quality of DVD video (720 x 480 pixels), QVGA is almost equal to the resolution of the video era the era of first VCD (325 x 288 pixels).
So the advantage of HD video is in terms of video technology maturity, with a resolution that is equal to the quality of broadcast or Blu-ray disc. So it's definitely HD video compatible with a variety of LCD TVs, LED or plasma HDTV that has a label. But on the other hand with increasing the resolution, of course in addition to making the video to be sharp and detailed, it also brings a logical side effect of the large size of the video. When was the VGA format a 10-minute video material is only a 1 GB, then with an HD format video with the same duration can be sized up to 4 GB. That is to record an HD video camera needs to have a faster processor and larger buffers to accommodate the high data rate of HD video. Plus memory cards used must have high data writing capability. When HD video files transferred to the computer, we need a large space remaining on the hard drive and need a high performance computer processors anyway to do editing.
More about HD video
This time we will review more about HD video, hopefully the more you can understand and can make choices based on their individual needs.
HD 720 or HD 1080?
HD 720 or 1280 x 720 pixels is the minimum resolution for a video to be appropriately referred to as HD video. While the HD 1080 or 1920 x 1080 resolution is the ideal resolution of an HD video (commonly referred to as full HD). Differences were not significant when viewed on television screens, but very different in file size. If its main purpose is to pursue quality HD 1080 then certainly the main answer, but if just want to enjoy the HD 720 HD video is very adequate for day-to-day.
The example above illustrates the difference between the quality of HD 1080 (left) against HD 720 (right) where the HD 720 are still visible boxes or less detail / less subtle when compared with the HD 1080.
Progressive or Interlaced?
Progressive only. Interlaced scanning is a technique that has been abandoned earlier times. Usually manufacturers will write the letter 'p' or 'i' in the code behind the HD video. For example HD 720p or 1080i HD. Generally, all 720 had progressive HD format, medium format HD 1080 there is still interlaced.
The picture above shows the characteristics of interlaced video have lines scanning results.
CCD or CMOS sensor?
Both CCD and CMOS sensors can be used to record video. Because the physical properties of the sensor itself, then the CCD sensor is only able to support the HD 720 to HD 1080 is CMOS. CMOS sensors can even create video clips with a wide selection of frames per second ranging from 24 fps, 30 fps and 60 fps. CCD sensors have a weakness when recording a bright spot where it will leak visible pixels (termed blooming). This effect can be seen on the screen during preview (before recording) and the results of the videotape.
CMOS sensors are safe from blooming but had problems with movement, where if the camera (or object) to move when the video recording will occur due to rolling shutter skew effects. This occurs because the process of taking data from each row of pixels in CMOS sensors performed in sequence (the CCD performed at once). Rolling shutter effect will make the lines appear curved and quite disturbing, like the example in the picture above.
Compression MPEG4-AVC (H.264) or M-JPEG?
h264Dalam broadcast world, MPEG-4 generation to 10 (or H.264) has been recognized as the standard compression techniques, replacing MPEG-2 that has begun to age. The advantages of this compression is high efiesiensi so despite a full HD format video using 1080 but still has a relatively small size. Not all HD cameras provide this compression technique, generally only provide conventional Motion JPEG compression.
Cameras that use MPEG-4 AVC codec will save the video files with the extension MPG, MJPEG codecs are going to give the file with MOV extension. As a comparison, to do video editing using MPEG-4 is still an obstacle. Differences with MOV video editing can be done using any editing program.
Stereo or mono?
What's an ugly sound when HD video. For that stereo sound is still preferred over mono. There are not many cameras that provide a built-in stereo microphone, consider again the specifications of each camera. Of course, a camera that can record stereo audio with dual mic that is left and right as the following example:
stereo
Optical zoom or digital zoom?
Initially, and today is still widespread, the camera can not optically zoom while recording video. The main reason for using the optical zoom motor sound will come on video. Now some cameras have started to allow us to zoom optically, either by repairing motor zoomnya or by turning off the mic for a moment when zooming. Zoomnya camera manual (played in the lens) is certainly not a problem with the sound of this bike.
When the camera does not allow optical zoom, check whether there is a digital zoom feature for video. Unlike the digital zoom on the photo that makes the result so ugly, the digital zoom on the video just do cropping and should be able to keep the video quality remains good.
Regular camera or digital SLR camera / large sensor?
This is important. Features HD movie disedikan in a wide range of cameras, ranging from pocket cameras, DSLR cameras and camera mirrorless. Although carrying the same resolution, not all cameras have the same sensor size. Small sensors are less sensitive to light, and will be forced to noise when recording in low light conditions. Large will be more sensitive sensors capture light in low light conditions so that even if forced to record without the help of adequate lighting, using cameras to record such a large sensor mirrorless cameras (eg Micro Four Thirds) camera let alone DSLR will be easier.
In addition in terms of sensitivity to light, the difference between the camera sensor will influence the DoF (depth of field) of video recording. Compact cameras or cameras with small sensors will give the space a broad sharp, arguably the area close to and distant from the camera will be equally focused. For that features auto focus when recording video with a small sensor camera is not really a serious issue. On the other hand, large sensor camera will be very sensitive to focus. Effect videos taken with a large sensor will resemble a movie (cinematic effect) so that it looks professional (if done correctly). But if not exactly in the set focus, then it will be easy in case of an annoying out of focus like the example below. This is compounded with most DSLR can not auto focus when recording video, we have to adjust the focus manually on the lens.
Conclusion
HD video feature is in sight, a common standard and widely available. First, you decide our needs before buying, because despite all the cameras has brought HD logo but not necessarily according to our wishes. Some facts can not be denied as the large size of HD video files, and how busy dealing with large files. Specify your preferences wisely, whether enough HD 720 or HD 1080, whether to H.264 or MJPEG. Recognize the blooming effect (for the CCD sensor) or skew (for CMOS) video recording and avoid conditions that could potentially produce these effects. Make a prediction of whether you will often record video in the room (likely dark) or outside the light? Lastly, if you want video results will such a movie theater or simply mediocre.
