Color (9.15)
So that consumers can compare cameras directly, we use standardized tests to measure the color performance. We photograph a GretagMacbeth color chart under tungsten light, adjusting each camera to get the best performance possible. Then, we analyze each image with Imatest software, the industry standard software for evaluating camera performance and image quality. As part of the results it creates, Imatest takes the camera's image of the GretagMacbeth chart, and in each square, superimposes a swatch of the ideal reproduction of the color, and a luminance-corrected version of the camera's color. In the image below, the outer squares are the Panasonic LZ5's rendition of each color. The vertical rectangles are the colors as they should be reproduced, and the inner squares show the ideal colors corrected for luminance.
Panasonic LZ5 - Standard
Panasonic LZ5 - Natural
Panasonic LZ5 - Vivid
Our second Imatest chart shows essentially the same test information. The small squares show the ideal rendering of the color chart's colors, while the circles show the color that the LZ5 produced. The longer the line between the two, the less accurate the color. The LZ5 over-saturated colors by 6.1 percent. Though we're always impressed to see a point-and-shoot camera score close to a perfectly accurate 100 percent saturation, the LZ5's 106.1 percent score is very respectable among compact cameras. It over-saturates reds and oranges more than other colors, which ought to yield rosy complexions and bright flowers. Though our standard is precisely accurate color, we assume that the LZ5's inaccuracy is intentional – many users will like the healthier-than-real skin tones the camera produces.
Panasonic LZ5 - Standard
Panasonic LZ5 - Natural
Panasonic LZ5 - Vivid
In Natural mode, the LZ5 scored an excellent 5.09 mean color error, indicating that, even though the reds and oranges are a little too bright, they are very close to the correct tint. The only colors that were significantly shifted were blue-green tones. Again, this is a user-friendly error – we don't think that most LZ5 owners will object to the error in these colors.
The LZ5 delivered this impressive performance in Natural color mode, not the Standard mode, which is the camera's default setting. Fortunately, Panasonic included multiple modes for users to select from – Natural, which produces accurate colors, Vivid, which yields heavily saturated colors, and Standard mode, which offers a mix of the two.
Still Life Scene
The Panasonic LZ5's view of our not-at-all lifelike “still life” scene is reproduced below.
Panasonic LZ5- Standard Color Mode
Panasonic LZ5- Natural Color Mode
Panasonic LZ5- Vivid Color Mode
Click on the images above to view the full resolution versions.
Resolution (3.64)
Digital cameras are often marketed and priced by the number of megapixels they deliver. The number of megapixels on the chip is a rough guide to the amount of detail a camera can deliver, but to really tell a camera's resolution, we test it. We photograph a standard resolution test chart, and use Imatest software to analyze the resulting images. Imatest reports resolution in line widths per picture height (lw/ph), which tells theoretically how many parallel lines the camera could resolve in a single image. For many reasons, the result is always smaller than the result that an absolutely perfect lens, sensor and image processor would deliver.
In the case of the LZ5, we tested the camera's three aspect ratios. The LZ5 was about average among compact cameras in the 6-megapixel range, delivering 1653 lw/ph horizontally and 1504 lw/ph vertically in 4:3 mode. We'd expect it to produce sharp 5x7-inch prints, and 8x10's that most users will enjoy. We got our best results with the zoom set at 16.1mm (equivalent to 98mm in 35mm format) at f/2.8. The results deteriorated a bit in other image formats. At 3:2, the LZ5 delivered 1423 lw/ph horizontally and 1430 lw/ph vertically. At 16:9, we detected 1353 lw/ph horizontally and 1269 lw/ph vertically.
Click on the image above to view the full res. file
The link above leads to a full-resolution test chart. It's worth noting that the edges and corners of the image are darker than the middle. We also see color fringing in the image – flaws in the lens design add red and blue halos to the edges of objects. It's easiest to see on high-contrast subjects like the test chart.
All digital cameras sharpen images as they record them, and Imatest detects this as well. Compact cameras tend to over-sharpen, and the LZ5 follows the trend. Interestingly, its over-sharpening is minor in the standard 4:3 format and 3:2, but jumps to an excessive level for 16:9 shots. At 4:3, it over-sharpens 5.86 percent horizontally and only 1.78 percent vertically. At 3:2, the numbers are 5.53 percent horizontal and 3.11 vertical, but at 16:9, it oversharpens 14.1 percent horizontally and 12.8 percent vertically.
Noise – Manual (4.42)
Noise in photos is the random variations in brightness and color from pixel to pixel that isn't present in the subject matter. It can look like the grain in a photo taken with film, or like the distracting texture in the image from a poor television signal.
Noise results can vary, depending on a camera's parameter settings, so we tested the LZ5 in both Standard and Natural mode. Again, we use Imatest software and the GretagMacbeth test chart to produce standardized results. In Natural mode, the camera performed better than any other Panasonic Lumix camera we’ve tested. Noise levels were a bit higher than desirable at low ISOs, but ISO 200 and 400 handled noise reasonably well. Standard mode was not as good, but still slightly better than other Panasonics. We also tried the Vivid setting, which significantly boosted just about every problem we could identify in image rendering.
The chart below displays the LZ5's noise performance at its various sensitivity settings; the horizontal axis shows the ISO setting used, while the vertical axis displays the corresponding noise.
Oddly, the LX5 performed better at ISO 100 than 80 in the noise tests. This result was constant across modes.
Noise – Auto (1.67)
With the ISO set to automatic, the LZ5 produced images that would roughly equate to ISO 180 on the manual side. This is not bad as far as metering performance goes, but the camera also produced a good deal of lower sensitivities. In general, images shot with the LZ5 in our well-lit studio setup contained more noise than we would expect in those conditions.
Low Light Performance (5.25)
We tested the Panasonic LZ5’s low light performance by taking series of exposures at various light levels. We test at 60, 30, 15, and 5 lux, to approximate typical low light conditions. 60 lux is looks like a moderately lit bedroom, while 30 lux is about the same amount of illumination as a 40 watt lightbulb. 15 and 5 lux are near darkness and force the camera to prolong exposures to achieve proper tonal levels. We shut off the camera's flash for this test, and set the camera to its highest ISO. The LZ5's manual controls wouldn't allow us to set long enough exposure times for the tests, so we had to use the Night Scene mode, which sets the ISO to 80.
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Because of the low ISO setting, the LZ5's images showed less noise than competing cameras. Unfortunately, the shots also show remarkably bad color performance – at 60 lux, saturation jumped to 140.7 percent with a mean color error of 14.6, with an exposure time of only 0.625 seconds. At 5 lux and a 4-second exposure, over-saturation was still unacceptably high at 134.4 percent, and mean color error had jumped to 20.3.
Dynamic Range (5.5)
Dynamic range is the difference between light and dark. On a photo print, that's the difference between the pure white of the paper, and the darkest black the ink or pigment can produce. In the real world, the dynamic range is much wider – there might be both sunlit snow and a black object in shadow, both in a single scene. One of the challenges cameras face is translating such brightness differences from the real world to a convincing photo. We test dynamic range by photographing a target that shows a row of progressively darker rectangles. The target shows more than 13 stops of brightness, which exceeds the range of the cameras we have tested. We analyze the images with Imatest software, which shows how many stops the camera renders with High Quality and with Low Quality. These results show the maximum dynamic range that each camera can capture. It is unlikely that any camera would match its results on this test in real-world shooting, but the tests provide a standardized means of comparing cameras.
The Panasonic LZ5 gave us unexpected results in the Dynamic Range test, and we really can't quite explain what we see. In general, the test shows the LZ5 to be typical of compact cameras – it performs best at low ISO, and, generally, higher settings look worse. However, oddly the LZ5 showed more dynamic range at ISO 200 and looked better than 100. Part of the issue may be that the LZ5's performance at ISO 80 and 100 is poor, while it reaches more average performance at 200.
Panasonic LZ5 - Dynamic Range, ISO 80
Panasonic LZ5 - Dynamic Range, ISO 400
Speed / Timing
Start-up to First Shot (7.46)
The Lumix LZ5 takes 2.54 seconds to start up, from sliding the power switch to capturing an image, so users ought to turn it on before they get into a situation where sudden photo opportunities pop up.
Shot to Shot Time (9.67)
The Lumix LZ5 has three burst modes: H, L and Infinite. In our testing, H, or High, mode recorded 3.4 frames per second for 6 frames; L, or Low, mode captured 2.5 frames per second for 6 frames, and infinite shot at 1.2 frames per second until the SD memory card was full. All the tests were done with a standard 128MB SanDisk SD card and fresh NiMH batteries.
Shutter to Shot Time (8.24)
The Lumix LZ5 is a bit slow to take a shot when the user doesn't pre-focus. From pressing the shutter to grabbing the shot, the clock ticked 0.4 seconds when the Lumix LZ5 wasn't prefocused. With focus already set, the LZ5 got off the shot much faster – in 0.04 seconds.
