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Tuesday, November 2, 2010

Camera Tech You Need To Know About

These days, a lot of innovation in photography is starting out in lower-end cameras. Some of these features are going to change the way you work as a pro.

This Article Features Photo Zoom

Built-in features like auto HDR (a mode in the Pentax K-5) will become increasingly useful to pros.

Will pellicle mirrors find their way into pro cameras? Could well be. Current technology can provide speed with a moving mirror: Canon’s EOS-1D Mark IV can shoot 16.1-megapixel images at 10 per second, and Nikon’s D3S can do full-frame, 12.1-megapixel images at 9 fps and 5.1-megapixel, DX (APS-C)-format images at 11 fps—with a conventional moving SLR mirror and with continuous auto focusing for each shot. But these are $5,000 cameras, and neither could be considered compact. The Sony SLT models could herald a new sort of quick, compact pro DSLR sometime in the future.

HD Video
Low-resolution video had been available in compact digital still cameras for years. The technology finally came to the DSLR, in high definition, with the Nikon D90, and soon thereafter, the Canon EOS 5D Mark II late in 2008. Video in DSLRs has caught on so well that almost all new DSLR models offer it.

HD video can be 1920 pixels wide by 1080 lines deep, or 1280 pixels wide by 720 lines deep. (By comparison, standard-definition digital video is 640 pixels wide by 480 lines deep.) Canon’s HD DSLRs, Nikon’s D7000 and D3100, Pentax’s K-5 and Sony’s SLT-A55 and SLT-A33 record 1080p video. Other HD DSLRs record 720p (Nikon’s D3S, D300S, D90 and D5000; Olympus’ E-5 and Pentax’s K-7, K-r and K-x). HD DSLRs also offer different video frame rates. Some feel that 24 fps, which is the same rate as feature films, produces a more cinematic look, others feel that 30 fps, which is the video standard, produces a smoother look. Some cameras will shoot at 60 fps, which provides an even smoother look with action subjects. The Pentax K-5 and K-r do 25 fps, a standard rate for European PAL video, but unusual for the U.S.’s NTSC video.

The Sony NEX-VG10 is a true hybrid that uses an APS-sized sensor and shoots full HD video and full-resolution stills.

Video in DSLRs allows you to record motion and sound, as well as pro-quality still images. The image sensors in DSLRs are much larger than those in most HD camcorders, providing better low-light and high-ISO images and a cinematic reduced depth of field that allows the user to create effective selective-focus shots. Based on prices of new models with video compared to their video-less predecessors, the HD feature is almost free, so that makes it a great deal.

That said, there’s a difference between HD video from a DSLR and HD video from a pro HD camcorder. The camcorder generally has a sensor (or sensors, in tricolor cameras) with the resolution of the video: 1920x1080 for full HD camcorders, 1280x720 for HD camcorders. HD DSLRs all have sensors with far higher pixel counts than that, so the images have to be downsampled to 1920x1080 or 1280x720 pixels for video. Image quality suffers in the process, due to the artifacts of downsampling. The CMOS still-camera image sensors also seem vulnerable to the “jello” effect in panned shots—because the images are scanned from top to bottom, a panned subject will waver in the resulting images. Newer DSLRs handle this better than early video DSLRs, but it still can occur and needs to be worked around.

Another consideration is that DSLRs were designed to still photography and aren’t as ergonomically suited for video work, nor do they generally have such camcorder features as eye-level viewfinders (the DSLR finder blacks out during live-view/video shooting, so you have to use the LCD monitor on the back of the camera to compose).