Sony Cyber-shot DSC-F707Wow! 5 megapixels, a super-sharp lens, Hologram AF, NightShot, NightFraming and more! Killer technology, great photos from Sony!<<Viewfinder :(Previous) | (Next): Exposure & Flash>> Page 5:OpticsReview First Posted: 08/20/2001 (Full production model update 11/20/2001) |
OpticsThe F707 is equipped with a super-sharp 9.7-48.5mm Carl Zeiss lens (equivalent to a 38-190mm lens), and an impressive 5x optical zoom. The aperture can be adjusted automatically or manually, and ranges from f/2-2.4 to f/8 depending on the zoom setting. (This is a significant increase in maximum aperture from the lens on the earlier F505V, which had a maximum aperture that ranged from f/2.8-3.5.) An additional 2x digital zoom function (10x total zoom) can be turned on and off via the Record menu, but remember that quality is always an issue with digital enlargement. That said, the F707 employs Sony's Precision Digital Zoom, which we have found to produce less quality degradation than the normal digital zoom used by other digicams. (One difference seems to be that the required interpolation is done with raw CCD data, before the JPEG compression is applied.) The F707's zoom control is nice and smooth, with a two-step rocker switch that lets you zoom slowly or quickly. This made it easy to make small adjustments to the zoom without going too far in either direction, a very nice feature for critical framing. A zoom bar appears on the LCD screen, reporting the zoom position, along with an indicator to show when the digital zoom kicks in (if Digital Zoom is activated through the Setup menu).
The rotating lens barrel continues to be one of our favorite designs, although the bulky lens takes some getting used to. (Actually, we're a little conflicted over the design: We love the flexibility it gives, but find it a little awkward to hold in most situations.) The lens pivots up and down approximately 135 degrees, greatly multiplying your shooting options. It's especially handy for grabbing ground-level macro shots or when holding the camera above your head to shoot over a crowd. The tripod mount on the bottom of the lens barrel provides even greater flexibility when working with a tripod or monopod, allowing you to tilt the camera's back panel for easier viewing. Sony offers both wide-angle and telephoto converters as accessories for the F707, which are mounted over the lens via the 58mm filter threads that line the inside lip of the lens barrel. Having the tripod mount on the lens centerline also makes it easier to align multiple shots to be used later to assemble a panorama.
Focus on the F707 ranges from 19.7 inches (50cm) to infinity in normal mode, and from 0.8 to 19.7 inches (2 to 50cm) in Macro mode. The Macro function is controlled via the Right arrow button on the Four Way Arrow pad, and is only available when the focus is in Auto mode (Manual focus mode includes the macro range). A Focus switch on the side of the lens selects either Auto or Manual Focus control. The F707's Autofocus mode employs a contrast-detection system to automatically determine focus. Manual focus is set by turning a focus ring at the end of the lens barrel, just as you would a standard 35mm camera lens. When using the Manual focus, a small indicator appears on the LCD screen that shows the focal distance in meters as you turn the ring. Also, an Expanded Focus option (activated in the Setup menu) automatically magnifies the image by 2x when you turn the focus ring, allowing for more fine-tuned focus adjustments. We really liked the feel of a digicam with a manual focus that works similar to that on a standard 35mm camera lens. If you're making the transition from a film camera though, the F707's focus ring may take a little getting used to. It isn't directly coupled to the lens elements, but rather just instructs the camera's CPU which way to move the focusing elements. This leads to a sense of disconnection between movements of the focus ring and corresponding focus changes that takes some getting used to. Also, the proportionality between focus-ring movement and focus adjustment seems to be a pretty strong function of the speed with which the ring is turned. If you move the ring slowly, it can take many turns of it to traverse the full focal range, while a quick twist will switch you from infinity focus to a couple of meters with only a partial rotation. This variable proportionality is doubtless an attempt to deal with the slow slew rate of most "fly by wire" digicam focusing systems. It definitely improves the focus response relative to other cameras we've worked with, but we still find manual focusing on the 707 to be a somewhat disconcerting experience.
We were also impressed by Sony's Hologram AF system for low-light focusing, which uses a laser diode and tiny holographic diffraction grating to project a crosshatched pattern of bright red lines on the subject. The nifty thing about the hologram is that the projected pattern stays more or less "in focus" almost irrespective of subject distance, so there's always a sharp pattern for the camera to focus on. Hologram AF isn't only for low light, you'll see the camera use it in fairly normal lighting as well, if there's not enough contrast in the subject to use the normal contrast-detect AF system. Try pointing the camera at a blank wall in normal home / office lighting, and you'll see the pattern. The screen shot at right shows a camera's eye view of the Hologram AF pattern, as the lens zooms from wide to telephoto.In actual use, we found the Hologram AF system made low-light and low-contrast focusing practically foolproof. In fact, it was hard to get an out-of-focus photo with the F707, in almost any situation.
Reader Comments! --> Visit our discussion forum for the Sony Cyber-shot DSC-F707!
Follow Imaging Resource: