Color (6.01)
The Kodak EasyShare P850 carries a Kodak Color Science Chip that the company claims produces extremely accurate colors. We tested this statement by heading into the testing studio and taking well lit shots of an industry standard color chart manufactured by GretagMacbeth. We loaded the images into Imatest imaging software, which compared the P850’s colors to the original colors of the chart. The program modified the chart to show the differences between the colors; it is shown below. The outer square of each tile shows the Kodak P850’s color; compare this with the original color shown in the inner vertical rectangle within each tile. The inner square in the tile shows the camera’s color corrected for luminance.
In case the naked eye cannot decipher the differences in the color, there is a chart below showing the degree of error more plainly. The squares on the graph below show the original colors of the GretagMacbeth chart, while the circles represent the colors produced by the Kodak EasyShare P850.
The line connecting the two shapes shows the degree of error, and most colors remain leashed with the exception of the blue end of the spectrum. These results aren’t as good as the flagship P880’s, which received an overall score of 8.24 and a mean color error of 7.28. In contrast, the Kodak P850 had an overall 6.01 score and an 8.57 mean color error. The P850 kept its saturation under control; it over-saturated by only 3.3 percent.
In all, the Kodak EasyShare P850’s colors were pleasantly saturated, but quite inaccurate – a disappointment in comparison to the flagship of the series.
Still Life Scene
Below is a shot of our still life array captured with the Kodak EasyShare P850.
Click on the image above to view the full resolution image (CAUTION: Linked file is very large!)
Resolution (2.63)
The Kodak EasyShare P850 advertises 5.1 effective megapixels on its 1/2.5-inch CCD. We tested the camera to see just how effective its resolution is in creating sharp images by taking a series of exposures of an industry standard resolution chart at various focal lengths and apertures. We uploaded the images to Imatest, which determined that the picture below is the sharpest the Kodak EasyShare P850 produced. It was taken using an 18.3 mm focal length and an f/4.5 aperture.
Click on the chart above to view the full res shot
Imatest output the resolution results as units of lw/ph (line widths per picture height). This unit describes how many vertical or horizontal black and white lines could fit across the P850’s frame without blurring them together. The Kodak EasyShare P850 resolved 1351 lw/ph horizontally while under-sharpening 5.51 percent. It read 1069 lw/ph vertically with 11.9 percent under-sharpening. The lack of in-camera sharpening is a familiar tale; the Kodak EasyShare P880 had hardly any sharpening with just four-tenths of a percent. This is one instance where the camera does appear intended for a more ‘enthusiast” type audience, reserving sharpening for post-processing and enabling users to determine how much sharpening the final JPEG or TIFFs receive.
While the overall resolution score of 2.63 is quite disappointing for this model, the image above should be seen as a starting point more than a representation of the camera’s potential. The shot above portrays the out of camera JPEG that many users would use as a base or background image for editing.
Noise – Auto ISO (3.42)
When we tested the noise levels in well lit images taken using the automatic ISO setting, the Kodak P850 performed averagely. It did meter the scene well and choose a reasonably low sensitivity setting of ISO 80, but there is still a decent amount of noise at the low end of the ISO range. Still, the Kodak EasyShare P850 pulled out a 3.42 overall automatic ISO noise score – better than the P880’s 2.79 score.
Noise – Manual ISO (3.51)
The Kodak EasyShare P850 has a vast number of manual ISO options, moving in 1/3-stop increments, but they are all crammed within a relatively short range of 50-400. Below is a chart showing how each of the ten settings handles noise. The ISO settings show up as dots on the horizontal axis and the accompanying noise levels show on the vertical axis.
The chart shows a steady rise in noise all the way to 400. The problem is that there is already a substantial amount of noise on the lower end of the ISO range. Just to show some comparison, the Fujifilm FinePix F30’s ISO 3200 setting produces less noise than the Kodak EasyShare P850’s ISO 400 setting. The P850 earned an overall manual ISO noise score of 3.51, which isn’t as good as the P880’s lackluster 4.36 score.
Low Light Performance (5.75)
To see if this “Performance Series” camera can actually perform in low light, we tested it in ever dimming illumination of 60, 30, 15, and 5 lux. We used the GretagMacbeth color chart as the test target so consumers can compare the camera’s low light shots with its optimally lit shot in the color section above. The first two light tests are fairly common situations. Think dank basement lighting. The latter two tests are very dark; it’s hard to even find the shutter release button. However, these tests show any limitations on the image sensor.
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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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All of the images, even those in the more common lighting levels, are under-exposed. They just become more so as the light wanes. Sure, there are versatile controls and decent shutter speed selections, but the maximum ISO sensitivity of 400 doesn’t help. The noise shows up as random splotchy green and purple speckles throughout the image; pictures get noisier the longer the shutter remains open. To see just how much noise is produced, check out the chart below. The exposure time is displayed on the horizontal axis and the noise level on the vertical axis.
Noise levels are high, but there isn’t a huge jump from one second to the next. This chart is definitely different looking than the P880’s, which showed a steep slope of noise but that camera used shutter speeds only to seven seconds. Overall, the Kodak EasyShare P850 isn’t the best camera to use in low light but will suffice in a bind.
Dynamic Range (5.5)
Lots of common photographic subjects have very wide dynamic range – a big contrast between the brightest and darkest parts of the scene. Take, for example, an indoor shot with a window in the background. On a sunny day, the scene outside the window will often be much brighter than the room. Our dynamic range test indicates how well cameras will handle challenges like that.
We use a standardized test for dynamic range, photographing an Stouffer step wedge, a target used in the graphic arts industry. Imatest software, which we use for much of our testing, analyzes images of the Stouffer target, and gives dynamic range figures for various quality levels. Dynamic range is measured in EV, or stops of exposure. A dynamic range of 7 EV means that the lightest object that shows detail in the image is 7 stops brighter than the darkest area with detail. We look at High Quality, which measures the dynamic range the camera achieves with 1/10EV of noise or less, and Low Quality, which measures the range with up to 1 EV of noise. Even though it seems that Low Quality wouldn't be of much use, with so much noise, it's an indicator of whether the shadows and highlights will have a hint of texture.
The Kodak 850 delivers fair performance at low ISOs. Up to ISO 100, its performance should be good enough for most situations, including outdoor scenes in bright sunlight. At ISO 200 to 400, however, its range is limited, and users should avoid contrasty lighting. Interestingly, the 850's High Quality performance is much worse than its Low Quality results – there is more of a difference between the two than we typically see. That's too bad, because it indicates how limited the High Quality range is.
Kodak P850 - Dynamic Range - ISO 50
Kodak P850 - Dynamic Range - ISO 400
Speed / Timing
Startup to First Shot (4.87)
Nothing is more frustrating than coming on a photo opportunity, and having to wait for the camera to start up. The 850 is particularly frustrating, with a 5.1-second wait. That's long enough to fish some cameras out of camera bag AND switch them on.
Shot to Shot (9.58)
The 850 shot 5 frames in 2.07 seconds, for a respectable 2.4 frames per second. The speed is useful for action sequences, and getting 5 frames in a burst is an advantage over many competing cameras.
Shutter to Shot (7.92)
With professional digital cameras, and most film cameras, getting an action shot is mainly a matter of reflexes – if the photographer presses the shutter fast enough, s/he gets the shot. Consumer-level digital cameras are a different story – they add a long delay between the moment the shutter is pressed, and the moment they get around to actually taking a picture. We timed the 850, and it's slow. Over the course of more than a dozen trials, our most common result was 0.54 seconds. Half a second doesn't seem long, but it is when compared to many events people like to photograph – a jump shot, a kiss, birthday candles being blown out, a dog catching a Frisbee. And half a second is a long time to wait to have your picture taken: for posed pictures, it's long enough that may people assume the picture has already been taken, and turn away from the camera.
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