Digital Camera Home > Digital Camera Reviews > Olympus Digital Cameras > Olympus C-730 Ultra Zoom

Olympus C-730 Ultra Zoom 3.2 megapixels, a sharp 10x zoom lens, tons of features, and an affordable price! Select a topic Reference: Datasheet C-730 Photo Gallery! C-730 Sample Images --------------------------------- 1. Intro and Highlights 2. Executive Overview 3. Design 4. Viewfinder 5. Optics 6. Exposure & Flash 7. Shutter Lag & Cycle Time Tests 8. Operation & User Interface 9. Camera Modes & Menus 10. Image Storage & Interface 11. Video, Power, Software 12. Test Results & Conclusion --------------------------------- Print-Friendly Review Version Additional Resources and Other Links Reader Comments on C-730 Review --------------------------------- Digital Camera Comparometer (TM) --------------------------------- <-- Digital Cameras (Home) <-- Digital Camera Reviews Index <<Viewfinder :(Previous) | (Next): Exposure & Flash>> Page 5:Optics Review First Posted: 11/25/2002

Optics
The Olympus C-730 is equipped with an all-glass lens, with 10 elements in seven groups. The 10x, 5.9-59mm lens provides a focal length range equivalent to a 38-380mm zoom on a 35mm film SLR. (That's a moderate wide angle to quite a long telephoto.) Apertures range from f/2.8 to f/8, with the maximum aperture setting dependent on the lens zoom position, ranging up to f/3.5 at the maximum telephoto position. Normal focusing distance extends from 4 inches (10 centimeters) to infinity, although the near limit is a pretty strong function of zoom setting, ranging from 4 inches at full wide angle to 3.3 feet (1 meter) at full telephoto. The C-730 offers two Macro settings, the normal ranges from about 3 inched\s to 2.0 feet (10 to 60 centimeters). (I'm frankly a little confused by the Macro mode, as the camera seemed to focus into the macro range without the macro option being set.) Through the Record menu, a Super Macro option lets the camera focus as close as 1.6 inches (four centimeters). The Macro / Spot button on the back panel adjusts the focus range for closeup subjects, and includes an option for spot metering in Macro mode.

Autofocus is determined through the lens, using a contrast detection method. This means that the autofocus will work properly with auxiliary lenses, although it should be noted that add-on lenses will usually affect a camera's focusing limits. -Don't expect the C-730 to focus as close as it usually does when it has a telephoto adapter attached. A green circle lights solid in the viewfinder display whenever focus is set, and flashes if the camera is having trouble adjusting focus. A Full time AF mode adjusts focus continuously, rather than only when the Shutter button is half-pressed. Two AF area modes are available as well, iESP and Spot. In iESP mode, the camera bases focus on the entire frame, automatically determining the primary subject, based on the proximity of the subject to the camera. Spot mode looks at only the very center of the frame, the area within the black AF target marks on the viewfinder display. The C-730 also lets you adjust the AF area, through an option in the Record menu. Once enabled, you use the arrow keys to move the AF target marks anywhere in the frame (though only while in Spot AF mode). Finally, the C-730 features a manual focus option. Pressing and holding the "OK" button displays the AF/MF focus menu, as well as a distance scale that you can set to meters or feet. You then adjust focus with the up and down arrow keys. As an aid to accurate focusing, the center portion of the view enlarges whenever you're actively adjusting the focus setting..

The C-730's lens barrel incorporates body-mounted filter accessory threads that couple to Olympus' range of accessory lens kits, which extend the camera's telephoto, wide-angle, and macro shooting capabilities. (An adapter barrel is required though, to permit mounting the auxiliary lenses beyond the furthest extension of the 730's telescoping lens assembly.)

While the C-730's lens provides up to 10x optical zoom, the camera's 3x Digital Zoom increases that magnification to a maximum of 30x, although the digital zoom brings with it the usual reduction in resolution. Digital zoom is enabled through the Record menu and controlled by the Zoom Lever on top of the camera. Since so-called "digital zoom" just crops out and enlarges the central pixels from the CCD's image, it directly trades resolution for magnification. This will result in very soft images if you're working at the camera's maximum three-megapixel file size, but can be useful if you're only shooting at 640 x 480 for web or email use.

Geometric distortion on the C-730 was slightly higher than average at the wide-angle end, where I measured a barrel distortion of 0.9 percent. The telephoto end fared much better, however, as I measured only about 0.3 percent of barrel distortion. These are pretty good geometric distortion figures for such a long lens. Chromatic aberration was better than I expected for such a long-ratio zoom, although it was still fairly evident at the maximum telephoto setting, resulting in 4-5 pixels of color around the resolution target lines in the corners of the frame. (Chromatic aberration is visible as a slight colored fringe around the objects at the edges of the field of view on the resolution target shots.)