Sony T30 Optics
Like other members of the T-series, the Sony T30 uses "folded optics" to tuck a zoom lens entirely inside the camera body. This means there's no fragile telescoping lens mechanism extending beyond the front of the camera to get knocked or bumped, and also means that the camera starts up faster than average, because it doesn't have to wait for its lens to deploy. The downside of folded lenses is that we've generally found them to be more prone to producing softness in the corners of the frame than conventional designs. In the case of the Sony T30 though the folded lens design seems to deliver sharper than average results: There's some softness in the extreme corners, but it disappears pretty quickly as you move towards the center of the frame.
Numerically, the Sony T30's lens is a 3x zoom lens, equivalent to 38-114mm on a 35mm camera. That's a range from a modest wide angle to a moderate telephoto, slightly biased toward the telephoto end relative to the 35-105mm equivalent lenses that seem to be the standard for most digital cameras. The T30's lens has a maximum aperture that ranges from f/3.5 to f/4.3 depending on the zoom position. This is about average, slightly better than average at the telephoto end, where many cameras drop to f/5.6 or higher. (Smaller f-numbers mean larger apertures on the lenses, and better light-gathering ability.)
Arguably the biggest news with the Sony T30's optics though, is the incorporation of Sony's Super SteadyShot optical image stabilization technology. This counteracts camera shake at slow shutter speeds, greatly improving your ability to get crisp photos under dim lighting. Image stabilization is a technology that consumers have been a little slow to appreciate, as it does add to the price of a camera. Once you've experienced it though, you'll never want to own a camera without it. The difference when shooting under typical indoor and after-dark conditions is really dramatic. It's hard for us to objectively measure the effectiveness of different optical image stabilization approaches, but for what it's worth, Sony's Super SteadyShot system seemed to work very well indeed in our shooting with the T30. (See the photo of the cat in the User's Report (first page of this review) for a pretty dramatic example - A usable hand-held shot at 0.8 seconds!)
A typical 3x optical zoom range, with good performance.
2x Digital Zoom
The Sony DSC-T30 zooms over the equivalent of a 38-114mm range, typical among its class. Details are fairly sharp at wide angle, though with some noticeable blurring in the trees, as well as slight blurring in the corners of the frame. The 2x digital zoom takes it out to 6x total, though Sony's Precision Digital Zoom technology does a slightly better than average job of holding onto fine detail. (Sony's "Smart" digital zoom limits digital zoom magnification to just that which can be achieved by simply cropping the central image pixels from the sensor, to display at the currently chosen image size. It thus varies from zero digital zoom at the maximum 7 megapixel resolution, to a total (optical plus digital) of 14x at VGA resolution.)
A small macro area with very good detail and resolution. Flash exposes fairly well, but flash illumination is uneven up close.
|Standard Macro||Macro with Flash|
The Sony DSC-T30's macro setting performs pretty well, capturing a minimum area of 3.02 x 2.27 inches (77 x 58 millimeters). Detail and resolution are both very good, and there's very little softening in the corners from the lens. (Most cameras have some softening in the corners in macro mode, the Sony T30 has less than most.) The flash throttles down pretty well, but its light doesn't reach the left corners of the frame, and coverage is very uneven. (Plan on using external lighting for your closest macro shots with the DSC-T30.)
Moderate barrel distortion, though very high pincushion.
This is the tendency for the lens to bend straight lines outward (like a barrel--usually at wide angle) or inward (like a pincushion--usually at telephoto). The Sony Cyber-shot DSC-T30's 0.8% barrel distortion at wide angle is average among the cameras I've tested, although I personally feel that this level is too high. At the telephoto end, the T30's 0.5% pincushion is much higher than average.
|Barrel distortion at 38mm is 0.8%|
|Pincushion at 114mm is 0.5%|
Low to moderate, small effect on images at edges.
Top Left @ 200%
|Tele: very low
Lower Left @ 200%
Chromatic aberration was low to moderate at wide angle, with the strongest effect in the upper left-hand corner of the image. At telephoto focal lengths, it was almost non-existent, with only a trace amount in the lower left-hand corner. In both cases, the distortion decreases very rapidly as you move away from the extreme corners towards the center of the image, and so affects only a small portion of the total image area. (This distortion is visible as a very slight colored fringe around the objects at the edges of the field of view on the resolution target.)
Some softening in the left and right corners of the frame, strongest effect in the upper right corner at wide angle.
|Wide: slightly soft in the upper right corner.||Wide: sharp at center.|
|Tele: slightly soft in the lower left corner.||Tele: sharper at center.|
The Sony DSC-T30 produced slightly soft corners in a few shots, though overall results were quite good, the softness being confined to the extreme corners, and extending only a short distance into the frame. The most visible effect was in the upper right corner at wide angle, and in the lower left corner at telephoto.