High definition


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High definition

  1. 1. High definition (HD) is no longer the future. It’s here. With so much new terminology it isfrustrating for consumers to make sense of it all. Codecs, media, formats, compressiontypes—it’s all a mess of confusion. This article is meant to help you understand what’s goingon in the world of HD camcorders so that you can make sense of it all and make an informeddecision on your next purchase. Technically speaking, high definition (HD) is any video with amuch higher resolution than the previous format, standard definition (SD). Digitalcamcorders that record SD video have been around for quite some time now, with most ofthem producing video at a resolution of 720 x 480. This means 720 lines of horizontalresolution and 480 lines of vertical resolution. Many SD camcorders allow video to berecorded in either widescreen (a 16:9 aspect ratio) or traditional (4:3 aspect ratio), but theactual resolution of the recorded image usually remains at 720 x 480.With the increasing popularity of HDTVs, camcorders that record only standard definitionvideo are becoming less and less popular each year. In their place are HD camcorders,almost all of which record Full HD video at a 1920 x 1080 resolution. There are somecamcorders that record HD video at a lower resolution of 1280 x 720, but this resolution isusually reserved for cheap, ultra compact camcorders.For the sake of brevity, these two HD resolutions are often referred to by just their verticalresolutions, for example: 720p, 1080i, or 1080p. The chart below attempts to illustrate therelative size of the different video resolutions.Thats easy to understand, right? Full HD 1920 x 1080 video is the highest recordingresolution available on consumer camcorders today. 1280 x 720 video is still HD, but itdoesnt record with nearly as many pixels. Standard definition video is even smaller, with itstotal resolution being six times smaller than that of 1920 x 1080 video.But whats the deal with those little letters we put after righting the abbreviated resolutionsof 1080i and 1080p? Since video incorporates motion, there is an extra element when youtalk about video resolution. The "i" stands for interlaced and the "p" stands for progressive,both of which are different methods for recording video.With interlaced video, camcorders split up horizontal rows of resolution into odds andevens. First one set is refreshed, and then the other set. Each of these "fields" is refreshed,back and forth, each at 30 times per second. It happens fast enough that the human eyeusually cant see the slight lag time. However, when you pause a interlaced video clip, youllsee a distinct jugginses.With progressive video, the entire image is refreshed at the same time, 30 times per second.Qualitatively, this tends to produce smoother motion, and is often preferred for sportsshooting, because freeze frames will not have the same jugginses that 1080i produces.Most high-end HDTVs support 1080p resolution, although there are some that only supporta maximum of 720p. Consumer camcorders, however, is just beginning to offer 1080precording, with nearly all of them offering 1080i recording only. It is common to find lower-quality 720p recording options on HD camcorders as well.
  2. 2. There are a few consumer camcorders that allow you to record either HD or SD video, butthese models are far less common than youd expect. Most Sony HD camcorders offer SDmodes, but you are likely to not find SD options on camcorders from Canon, JVC, orPanasonic. If SD recording is a feature you require, make sure you consult the full camcorderspecs to make sure the camcorder youre checking out has it as an option.Is now the time to buy an HD camcorder?The short answer is yes. If youre in the market for a new camcorder, chances are youalready own an HDTV or have regular access to one. HD is so much in demand right now thatmost manufacturers dont even focus on new SD camcorders anymore. Shooting HD meansyoure recording in the highest-quality available in the consumer market, so you are future-proofing your memories for as long as HD exists. The only reason not to go with HD wouldbe if you dont own or dont plan on owning an HDTV in the near future, or if youre ultimategoal is to create and edit low-quality videos. SD video is easier to edit and upload to theinternet than HD, but even those caveats are falling by the wayside now that sites likeYouTube support Full HD content.Compression Types: Consumer HD camcorders record video digitally, so they use videocompression systems to keep file sizes from being outrageously large (theyre still very big,though). Here are some of the most common compression types youll find on todays HDcamcorders:AVCHD - Introduced in 2006, AVCHD has exploded in popularity and is now the mostcommon compression system for consumer camcorders. It is used on HD camcorders fromSony, Panasonic, JVC, and Canon, as well as on numerous DSLR cameras that record video.AVCHD once suffered from compatibility issues, but things have gotten better each year.Still, playing AVCHD clips on a computer can be a bit of a hassle as certain operating systemsdo not support the files. If this is the case, you must import the AVCHD clips using editingsoftware (like the software that comes with your camcorder) before you can playback yourclips. The clips do playback fine on your camcorder, however, and they look great whenviewed on an HDTV. Another setback of AVCHD is that it does not allow for 1080p recording,which is why most consumer camcorders only record 1080i or 720p.MPEG-4 - This format is used by some Samsung and Sanyo camcorders, as well as many ultracompact budget camcorders (like the Flip). What makes things confusing is that MPEG-4 isthe same codec used in AVCHD compression, so the two are very similar. The difference isAVCHD compression includes a variety of extra information for media presentation, which iswhy the clips are larger and full of more information. MPEG-4 clips can usually be draggedright from the camcorder onto your computer for playback—no importing process or specialmedia players are required.HDV - This is the oldest consumer high definition format and it is quickly fading intoobscurity. Todays consumer HDV camcorders only record in 1440 x 1080 resolution, thenstretch the footage to 1920 x 1080 for playback. Camcorders using HDV compression alsoonly record to MiniDV tape, as the format is not compatible with non-linear media.
  3. 3. MPEG-2 - Usually reserved for camcorders that record standard definition only, MPEG-2variants are also employed on certain professional HD camcorders. When used forcompression with SD camcorders, the MPEG-2 clips are usually saved with an MOD fileextension. Just like AVCHD clips, these files may have to be imported using editing softwarebefore they can be played back on your computer.A night vision camcorder is becoming more and more popular for those people who arelooking to invest in a camera to record themselves and family. Not only are these popularwith people looking to save those special moments like birthdays, family get together andgraduations more and more people are using these when hunting or searching for aparticular item at night. They are fantastic to take on camping trips especially if you plan todo a bit of late night fishing, being able to see what you are doing on the camcorder makes ita lot easier when attaching those lures to your line.You should be able to purchase a night vision camcorder from your local electronic store butyou should first determine what your camcorder is going to be used for. Is it going to beused around the home with family or do you plan on using it in a semi professionalproduction? Generally the more features your camcorder has, the more it will cost. Somecamcorders used in professional products can easily sell for close to $10 000.However if you are just looking for a night vision camcorder for general use then there are alot of options that you can look at. While I can’t give you specific models due to the fact theyevolve so quickly now that this information will become redundant I can give you some tipson what to look for.Battery life is a big plus; you don’t want your batteries draining fast so make sure that yourcamcorder has a long battery life. With regards to the night vision, the night vision image willprobably be your biggest factor and the only way to see what it is like is to give it a little test.Ask the salesman for a dark spot in the shop and turn on the night vision function. The imageshould not be too grainy and it should be clear.Another option instead of buying a night vision camcorder is to purchase a night vision add-on. This simply attaches to your camcorder and provides a light that is invisible to human butthe camcorder can actually pick up the infrared light which gives the camcorder the ability to“see” in the dark. One drawback of these however is that they are usually powered by thecamcorders battery and can quickly wear it down. On the plus side however is that they arevery cheap and can be purchased online for less than $40. One of these may be an option ifyou don’t want to buy a whole night vision camcorder.