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White Balance

Overall the results look pretty good, all of our color charts appear to have fairly good balance. A closer look at the actual measurements shows that the outdoor automatic white balance chart has a slight blue cast (although it's still good), fluorescent is virtually perfect and the incandescent shot has a subtle pink cast (although compared to the competition we'd consider it quite good).

Outdoor - Auto WB
Red -1.0%, Blue -1.3%
Good
Fluorescent - Auto WB
Red 0.1%, Blue -0.3%
Excellent
Incandescent - Auto WB
Red 2.2%, Blue -3.1%
Good

Flash Performance

The P700's built-in flash unit has a specified range of 3.6 m at wide angle and 2.5 m at telephoto (both at Auto ISO), that's about average for this kind of camera. The results from our flash test proved good, the color chart came out with good balance and no color cast, the skin tone test looking natural and again had no color cast.

Color chart - good exposure, no color cast Skin tone - good exposure, no color cast

Night exposures

The P700 has automatic noise reduction which kicks in for exposures of 1/8 sec or slower. It uses a 'dark frame subtraction' method which takes a second equally long exposure after the main shot (thus an 8 second exposure will take 16 seconds). This dark frame contains a similar noise pattern to the original shot and can be used to 'subtract' hot pixels from the final image. The results from the P700 were quite good especially in manual mode and locked to ISO 80.

ISO 80, 8 sec, F4.5 (manual exposure)

Macro Focus

The P700 has a very useful feature, in macro mode it will display the minimum focus range just above the zoom display as you zoom the camera. This goes up in steps (10 - 50 cm, 20 - 50 cm, 30 - 50cm , 40 - 50 cm), we obtained the best result (best frame coverage) at a mid-zoom position but still in the 10 - 50 cm range (although at this magnification there is some unavoidable chromatic aberration).

Wide macro - 117 x 87 mm coverage
26 px/mm (667 px/in)
Distortion: High
Corner softness: Low (with some CA)
Equiv. focal length: 33 mm
Mid-zoom macro - 71 x 53 mm coverage
43 px/mm (1086 px/in)
Distortion: Low
Corner softness: Low (with some CA)
Equiv. focal length: 53 mm

Barrel and Pincushion Distortion

The P700's wide angle of 33 mm equiv. could be considered slightly wide angle (certainly compared to some cameras which start at 38 mm). Taking that into account 0.9% barrel distortion is better than we would expect. At the telephoto end of zoom there is some pincushion distortion but it's unlikely that 0.6% will be visible in most shots.

Wide angle - 0.9% Barrel distortion
Equiv. focal length: 33 mm
Telephoto - 0.6% Pincushion Distortion
Equiv. focal length: 132 mm

Vignetting / Lens Shading

Our vignetting measurement is made by taking the average luminance value of the darkest corner of the image and comparing it to the average luminance at the center of the image, any difference greater than 15% may be visible in everyday shots. The P700 did appear to have an odd vignetting / lens shading problem, at wide angle the top left corner of the frame appears shaded, at telephoto this affects the top right corner more. It is possible that the level of lens shading at wide angle (especially larger apertures) may be visible in some shots.

Wide angle, maximum aperture (F2.8)
18.5% maximum fall off, top left corner
Telephoto, maximum aperture (F4.0)
10.3% maximum fall off, top right corner
Wide angle, stopped down (F5.0)
11.2% maximum fall off, top left corner
Telephoto, stopped down (F6.2)
7.6% maximum fall off, top right corner

Purple Fringing (Chromatic Aberrations)

On our standard test shot the P700 did exhibit some slight purple fringing in the corners at wide angle and maximum aperture. Scanning through our everyday gallery shots we only managed to find two or three examples which had any noticeable fringing and the one shown below was about the worse (and that's really not bad at all).

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33 mm equiv, F2.8 (max aperture)
36 mm equiv., F2.9 (max aperture)

Overall Image Quality / Specific Issues

Overall the P700 works well, as we have mentioned in other reviews the seven megapixel 1/1.8" CCD appears to be surprisingly good and can deliver some very nice images with relatively low noise (at lower sensitivities). Perhaps the P700's only image quality related weakness could be over-processing of images (see below).

Intrusive noise reduction

We mentioned this earlier in the review, the P700 appears to have an automatic noise reduction system which doesn't simply kick in for higher sensitivities but is in fact always active. This means that it attempts to clean noise from images which don't have any (or at least not enough to be objectionable), the outcome is that all too familiar watercolor look which can leave images looking slightly artificial and ultimately limits the camera's capability to resolve fine detail. Casio should either tune the NR system to only take effect on images taken at ISO 200 or above or provide the photographer the option to disable it.

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