Olympus D-490 ZoomOlympus updates a popular 1.3 megapixel model to 2 megapixels, with improved features.<<Viewfinder :(Previous) | (Next): Exposure & Flash>> Page 5:OpticsReview First Posted: 10/28/2000 |
Optics
The
D-490 comes equipped with a 3X, 5.4-16.2mm zoom lens (equivalent to a 35-105mm
lens on a 35mm camera) with a maximum aperture of f/2.8-f/4.4, depending on the
zoom setting. In normal mode, the lens can focus from 31 inches (80cm) to
infinity and in macro mode, from 8 to 31 inches (20 to 80cm). The TTL (through
the lens) autofocus function uses a contrast detection system which produces
sharp, reliable focus in well-lit conditions, but may have problems in low-light
situations. Low-light shooting is provided for with two preset "Quick Focus"
settings of 8 feet (2.5m) and infinity, selectable by pressing the up and down
arrow buttons on the Arrow Pad during exposure. (These seem to work well enough,
but we'd like to see more Quick Focus steps, or an autofocus-assist light for
better low-light operation, particularly since the camera does so well in dim
light with its variable-ISO capability.) The camera controls the aperture
automatically with settings of f/2.8 and f/8 in wide angle and f/4.4 and f/12.6
in telephoto mode.> The D-490's 3X optical zoom is controlled by a rocker toggle on top of the camera and pretty much lets you zoom in any increment. (The zoom lenses on some cameras have certain "preferred" positions, a limitation we didn't observe with the D-490.) An additional 2.5X digital telephoto increases the camera's total zoom to 7.5X, but image quality will deteriorate in direct proportion to the amount of digital enlargement. There was moderate optical distortion on the D-490, with the camera showing a 0.8 percent barrel distortion at the wide angle end, and about a 0.3 percent pincushion distortion at full telephoto. While it's more than we like to see, 0.8 percent barrel distortion is fairly typical at wide angle, and 0.3 percent pincushion is a bit better than average at telephoto. Digital telephoto and Macro modes are controlled by the same button on the back panel of the camera, meaning that you can't use the two together. However, the digital telephoto can be enabled at any zoom setting, not just at maximum optical zoom. This is an uncommon feature on digital cameras we've reviewed, but one that greatly increases the D-490's flexibility. Macro performance is quite good, as the camera captures a minimum area of 3 x 2 inches at the furthest telephoto setting.
Focus
> Camera focus is very straightforward, just point the camera at the subject, depress the shutter button halfway to initiate the autofocus and metering, then press all the way to shoot. The orange and green LEDs next to the viewfinder let you know when the camera is ready. If the orange LED blinks after metering, it means that the camera recommends using the flash due to slow shutter speed. As with most other digicams, the D-490 sets exposure and focus based on what's roughly centered in the frame, but this can be changed very easily. Simply center the subject you want to base your exposure and focus on in the viewfinder, depress the shutter button halfway, and continue to hold the shutter button halfway until you have repositioned the subject in the viewfinder to your original composition. When you fully depress the shutter button, the focus and exposure will remain locked on the area you have chosen.
Quick Focus
The D-490 also features a Quick Focus option, which is helpful in low-light situations, where the camera's autofocus sometimes has trouble. Quick Focus allows you to choose close focusing (2.5m/8ft), which gives you a depth of field of approximately 2.8 feet to infinity at wide angle and 5.9-13 feet at telephoto, or far away focusing (Infinity), which gives you a depth of field of approximately 4.3 feet to infinity at wide angle and 22 feet to infinity at telephoto. You choose one of these two options by pressing the up and down arrow buttons on the Arrow Pad on the back of the camera before depressing the shutter button halfway, and you must continue to hold down the arrow button while you take the exposure. The buttons are clearly marked on the camera - the 2.5m/8ft setting is the "down" arrow button and the Infinity setting is the "up" arrow button. Olympus touts this as a good feature when quick shooting is required, but you must think in advance of the exposure to locate the appropriate button before you frame your shot. We found it helpful to use the LCD monitor to frame the image, because you are already concentrating your attention on the back of the camera. Make sure that the appropriate icon shows up on the monitor before depressing the shutter release.
Macro Mode
Macro mode is accessible through the Macro/Digital telephoto button on the back panel (indicated with the standard flower macro symbol). The D490 does a very good job in the macro category, capturing a minimum area of just 2.86 x 2.14 inches (72.57 x 54.43mm). The LCD monitor is automatically activated when you enter the Macro mode and the macro flower icon appears on the display. The mode is just as quickly canceled by pressing the Macro button again twice.
Digital Telephoto
Controlled by the same button as the Macro mode, the D-490's digital telephoto offers up to an additional 2.5X zoom (depressing the Macro/Digital telephoto button twice enters the mode, and a third press cancels it). Digital telephoto settings of 1.6x, 2.0x, or 2.5x can be selected by using the up/down arrow keys on the Arrow Pad. The digital telephoto can be enabled at any zoom setting, but remember that digital enlargement somewhat compromises image quality. It simply crops out the central portion of the camera's sensor array, producing a smaller image. (The D-490 Zoom cannot be used in SHQ-TIFF mode when you engage the digital telephoto function.)
Reader Comments! --> Visit our discussion forum for the Olympus D-490 Zoom!
Follow Imaging Resource: