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Photographic tests

White balance

In common with most Kodak cameras the C875 has just four white balance presets in addition to the auto default; daylight, tungsten, fluorescent and open shade. There is no manual (measured or custom) white balance function, which is frankly inexplicable given it is an option on virtually every other camera these days. Fortunately the C875's auto white balance does an excellent job in most natural light situations (and not a bad job with mixed lighting either). Under tungsten (incandescent) light the results have only the slightest warm tone, but fluorescents can cause a serious color cast (no single 'Fluorescent' preset can deal with all the different tube types out there).

Auto White Balance Fluo Preset Auto White Balance Incandescent preset
Fluorescent light - Auto white balance poor, preset white balance average Incandescent light - Auto white balance good,
Preset white balance good

Flash

The flash is a little underpowered, but no more so than most of the C875's competitors. The quoted range is 13.5ft at the wide end and 8.5ft at the long end of the zoom (using auto ISO, which tops out at ISO 200) - fine for normal social snaps but not much more. Obviously you can increase the range by setting the ISO manually. Color is excellent but we found the C875 to underexpose slightly - something easily fixed in post-processing (or using the in-camera image enhancement option). If you get too close the flash also sometimes burns out highlight, but this was fairly rare.

Click here for flash test chart

Skin tone -
Excellent color, slight underexposure.

Macro

The C875's macro function gets you down to about 10cm (4 inches) at the wide end of the zoom, capturing an area just under 10cm across (73 to be exact), with distortion and corner softness well controlled. It's not the most impressive macro performance on the block, and we found shooting macro also caused a lot of focus errors, so if you like to get really close, this ain't the camera for you. At the telephoto (10x) end of the zoom the closest focus is 70cm (2.3 feet), and the area captured is just under 13cm across - not bad, but nothing to write home about.

Movie mode

As is now the norm on cameras of this type the C875 offers a maximum movie size of 640 x 480 pixels at 30 frames per second.

The movies are recorded using MPEG-4 compression (saved as QuickTime .MOV files), which makes them very small indeed - you can fit over half an hour of VGA (640 x 480 pixel) footage on a 1.0 GB card.

Overall quality is pretty good, especially given the very small file sizes. There is also a lot of hunting at the long end of the zoom if you use continuous AF.

There are some basic in-camera video clip editing facilities on offer (trimming).

Sample movie: 640 x 480 pixels @ 30 fps
File size: 3.56 MB, 7.17 secs, at full telephoto

Click on the thumbnail to view the movie
(caution: large file!)

Resolution

Resolution isn't as good as the best 8MP cameras, but it's not far short. The charts are slightly soft and show evidence of excessive in-camera sharpening (something you can at least turn down), there is a visible drop-off towards the edges and corners of the frame, and they're not that clean, but for a budget camera they ain't bad at all.

WIDE LENS Crops

Click here for the full resolution test chart

Horizontal LPH

Absolute resolution 1500 LPH
Extinction resolution 1900 LPH *

*moiré visible

Vertical LPH

Absolute resolution 1550 LPH
Extinction resolution 1950 LPH *

*moiré visible

Distortion and other image quality issues

The C875 exhibits moderately high distortion at the wide end of the zoom - 1.3% barrel distortion (click here for test chart) and there is some pincushion distortion (0.4%) at the telephoto end (click here for test chart). Note that the distortion isn't restricted to the extremes of the zoom range, but is visible in test conditions pretty much throughout the range to some degree. Not that any of this is going to be a major problem for everyday photography, but it's worth knowing if, for example, you want to use this camera to copy artwork; don't.

Overall image quality is actually pretty pleasing as long as you don't get too critical at a pixel level (and who buys a camera like this to look at the images at 100% on screen?). Exposure and focus are very accurate and color is, well colorful. This is one area where Kodak produces fairly mixed reactions; many love the slightly over-the-top Disney-esque saturation, though photographic purists tend to find it 'unnatural'.

Living in the UK where three quarters of the year is spent in a Dickens-style gloom I came to appreciate the C875's ability to pull some color out of the dismal winter light, and you can tone things down a little with the in-camera image controls, but be warned that the color - along with the fairly strong default sharpening - means that the images are not best suited to extensive post-processing.

Of course there are a few negative points to consider; at ISO 200 and above the noise reduction turns all fine texture into a watercolor-like smear (more on that below), if you look too closely there is evidence of noise reduction even at ISO 64. Then there is the usual highlight-clipping when shooting bright contrasty scenes (you really need to use some negative AE compensation), some corner softness at the long end of the zoom/widest aperture and a lack of biting sharpness combined with over-sharpening, but overall - given the pricing and feature set - it seems churlish to complain too loudly.

Noise

With tiny, high pixel count chips noise is always going to be an issue, and to a large degree this is more a test of the effectiveness (both measurable and visible) of a camera's noise reduction system. Designers have to balance the desire to produce smooth, clean results with the need to retain as much detail as possible (if you blur away the noise, you blur away image detail too)

The C875 - as the crops below show - has very little noise at all at ISO 64-400, and only a small amount at ISO 800. Does this mean Kodak has discovered the holy grail of digital photography, the noise-free 1/1.8" sensor? Erm, no. It means that the noise reduction is heavy. Very heavy indeed over ISO 200.

  ISO 64 ISO 100 ISO 200 ISO 400 ISO 800
Crops

Noise graph

Indicated ISO sensitivity is on the horizontal axis of this graph, standard deviation of luminosity is on the vertical axis.

As the graph shows, noise is very low indeed for a camera in this class, particularly at anything over ISO 100 (where the noise reduction really kicks in; noise at ISO 200 and 400 is actually lower than it is at ISO 100).

Low contrast detail

What the crops and graph don't show is the effect of noise reduction on low contrast fine detail such as hair, fur or foliage. An inevitable side effect of noise removal is that this kind of detail is also blurred or smeared, resulting in a loss of 'texture'. In this test the crops below show the effect of the noise reduction on such texture (hair) as you move up the ISO range.

100% Crops
ISO 64 ISO 100 ISO 200
 
ISO 400 ISO 800  

As the crops show, low contrast detail is perfectly good at ISO 64 and 100 (there is a little smearing of the most subtle detail, but nothing you'd worry about in a standard print). Once you get to ISO 200 and up the noise reduction has a strong, visible smearing effect on all the low contrast detail, giving an increasingly 'painted' effect to the images. This limits the usability of higher ISO settings for anything with fine texture unless you're only looking to produce very small prints.

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