Color (6.34)
Just like different films produce different tones of colors, digital cameras’ imaging processors reproduce colors in different ways. To test the accuracy of the Konica Minolta Z5, we took several pictures of the GretagMacbeth color chart and analyzed the results in Imatest Imaging Software. The chart below shows a comparison between the camera’s color reproduction and ideal colors. The outer squares in the modified chart are the actual colors produced by the Z5. The inner square depicts the color corrected version that users would see when they uploaded their pictures into a computer application. The inner vertical rectangle is the ideal color extracted from the GretagMacbeth chart.
More quantitative data is expressed below; the circles represent the produced color of the Z5; the squares represent the ideal colors on the GretagMacbeth chart. In a perfect world and on a perfect digital camera, the squares and circles should be right on top of each other. Unfortunately, the Konica Minolta Z5 is not all that perfect camera.
The Z5 received an overall color score of 6.34 with a mean color error of 9.28. Yikes! Colors across the chart are inaccurate: reds, greens, dark blues, and yellows. Just as disappointing was the 93.91 percent mean saturation score. Most digital cameras slightly over-saturate colors to enhance skin tones and give texture to flat surfaces; their scores usually hover around the 100-110 percent range. This DiMAGE is well below that mark, producing muted and often muddy tones.
Still Life Scene
Below is an image of our still life scene recorded with the Konica Minolta DiMAGE Z5.
Click on the above image to view a full resolution version (CAUTION: The linked image is very large!)
Resolution / Sharpness (3.98)
Konica Minolta released the Z5 with an advertised 5.2 total and 5 effective megapixels on its 1/2.5-inch CCD. To test the camera’s resolution, we take several exposures of the industry standard ISO 12233 resolution test chart. We analyze those images in Imatest Imaging Software and determine how many pixels were used. We compare the results to the advertised megapixel count and attach a score of “good” if it’s within 70 percent, “very good” if within 80 percent, and “excellent” if a camera is within 90 percent of the advertised megapixels. The Konica Minolta Z5 used 3.98 megapixels in our images, receiving a “very good” score by using 81 percent of the advertised 5 effective megapixels and producing crisp images with sharp definition.
Click on the chart to view full Res Image
Noise Auto ISO (1.83)
This is not the camera for night shots or beautifully clear landscapes. When we tested the Konica Minolta Z5, it scored a 1.83 overall noise score. This could be one of the worst scores we’ve seen in awhile, which is particularly unfortunate on an intermediate level digital camera. The excessive amounts of noise can be seen as discolored pixels when you click on the still life scene link and view the enlarged image (above).
Noise Manual ISO (3.95)
To determine how well the camera handles noise, we test levels at each ISO rating manually available. On the Z5, this includes the following ISO ratings: 50, 100, 200, and 320. We compiled the results from each test into a regression analysis and determined the overall noise score to be 3.95. This is better than the automatic ISO setting, but is nothing to brag about, facing difficulty at all sensitivity ratings beyond ISO 50. The Z5’s noise production can be perceived on the chart below: the horizontal axis shows the camera’s ISO ratings and the vertical axis represents the noise produced by the Konica Minolta Z5.
Low Light (6.0)
We test each camera’s performance in low light to determine exactly how far the camera can be pushed without the assistance of a flash or accessory light source. The test is designed to illustrate the camera’s responsiveness to light and the degradation of color that results as light levels fall. Depending on image quality and preference, many users will opt to use the flash rather then bring along a tripod and try to capture the scene atmospherically. Others may loath the typical direct, fixed flash aesthetic that has become all too familiar to digital photographers and value a camera’s nighttime capture potential in its pure rendition of the scene.
Below is a sequence of 4 exposures recorded in diminishing light. The images are captured in a controlled environment with careful attention paid to light levels and color balance. The progression illustrates how the camera responds to decreasing light levels in terms of color reproduction and noise. All exposures were recorded using the Z5’s Programmed Auto mode, an ISO 320 rating and customized white balance (oriented for each shot).
We recorded four images of our GretagMacbeth color chart, captured under light levels of 60, 30, 15, and 5 Lux. These levels aim to replicate typical low light conditions; 60 Lux approximates a moderately lit bedroom, while 30 Lux equates to a single 40 watt bulb, and 15 Lux and 5 Lux illustrate how the camera fairs in actual darkness (minimal illumination).
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Low Light Tests
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60 Lux
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30 Lux
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15 Lux
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5 Lux
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Above are four GretagMacbeth color charts that have been run through Imatest Imaging Software. Each chart expresses the camera’s performance at a specified light level. The chart is read in the same manor as in the above Manual and Automatic Noise sections of the review: the outer square is the camera’s produced color, while the vertical rectangle is the ideal and the middle square is the camera’s tone, corrected by the software.
The Konica Minolta Z5 performed admirably in low light in terms of color rendering and even noise. While the camera has some general color reproduction deficiencies, the decreased illumination did not impact the results. Noise levels were excessive, but usable even at 15 Lux. The camera did not completely break down until it reached 5 Lux. In 5 Lux, the auto focus method was rendered completely useless and could not generate a focused image. Although 5 Lux may seem too dim for any camera, it is not. Many imagers can adapt to 5 Lux (common for a bedroom lit by a single bulb — distanced from the source). All-around, I was impressed with the Z5’s low light performance and would consider using the camera for a night shoot, though the lack of a bulb exposure setting certainly comes into play. The shutter limitation of the camera restricts the exposure to 4 seconds, though it appears given a tripod, images can be captured at night that approach the imager’s potential in any situation when the ISO 320 setting is used.
Speed / Timing
Start-up to First Shot (6.66)
The Konica Minolta Z5 takes a leisurely 3.34 seconds to start up and take its first shot. This is quite a bit more time than most digital cameras in this category and is sure to hinder the highly performance-driven user.
Shot to Shot (8.88)
I did this test several times. The first time, the camera’s batteries were low on juice, so the Z5 took pictures about every four seconds. However, once I put in a set of fresh batteries, the camera performed considerably better. The Konica Minolta Z5 takes a picture about every 0.84 seconds in its Continuous shooting mode. The camera takes a few seconds rest every third picture and gets slower and slower the more you shoot. This burst mode is quite disappointing, considering other cameras within this category and price range offer 2 or 3 frames per second. This DiMAGE does have a Progressive mode, which shoots 10 frames per second at 1024 x 768-pixel resolution. This mode shoots as long as the user’s finger is depressing the shutter release button; however, the camera only saves the last 20 images. After testing this mode, it worked exactly how Konica Minolta said it would: ten frames per second.
Shutter to Shot (8.08)
When the DiMAGE Z5 is not already delicately focused, it takes .46 seconds to take a photograph. When it is focused, it takes the camera about a tenth of a second to capture the shot. This could be a problem with candid shots that won’t last longer than half a second.
