Compared to Nikon Coolpix 990 and Sony DSC-S70

Colour Chart Comparison

Shot in daylight, Auto White Balance, EV compensation +0.3 (all cameras), measured light ~10 EV.

Sony DSC-F505V Nikon Coolpix 990
Sony DSC-S70  

All camera show good white balance in daylight, good metering and colour accuracy. Obviously the S70 & F505V show stronger (more saturated) colours which are (to the naked eye) closer to the original test chart.

We're only measuring colour below. RGB values below were taken from a VGA reduced image (to average colours and eliminate JPEG artifacts) using the Eyedropper tool in Photoshop with a 5 by 5 Average Sample Size.

  Sony DSC-F505V
Coolpix 990 Sony DSC-S70
Patch White 178,182,182 201,201,201 182,182,182
Middle Gray 79,81,87 104,104,104 85,85,87
Patch Red 187,15,32 223,52,58 189,17,27
Patch Green 3,135,41 5,149,63 1,132,35
Patch Blue 40,25,123 60,50,112 33,26,123

Resolution Comparison

Shots here are of the PIMA/ISO 12233 standard resolution test chart (more available for comparison in our comparison database). Studio light, cameras set to auto, Exposure compensation +0.7 EV for all cameras. How to read the charts: All values are 1/100 th lines/picture height/width. So the "10" value equates to 1000.

Sony DSC-F505V
Nikon Coolpix 990
Sony DSC-S70

Measurable findings (three measurements taken for each camera):

Camera Measurement Absolute Res. Extinction Res.
Sony DSC-F505V Horiz LPH 950 1300
Vert LPH 950 1250
5o Diagonal 900 n/a
Coolpix 990
Horiz LPH 900 1300
Vert LPH 900 1400
5o Diagonal LPH 900 n/a
Sony DSC-S70 Horiz LPH 1050 1400
Vert LPH 1050 1500
5o Diagonal LPH 1000 n/a

Definition of terms:

LPH Lines per Picture Height (to allow for different aspect ratios the measurement is the same for horizontal and vertical)
5o Diagonal Lines set at 5o diagonal
Absolute Resolution Still defined detail (below Nyquist frequency*)
Extinction Resolution Detail beyond camera's definition (becomes a solid gray alias)
n/a Not Available (above the capability of the test chart)
n/v Not Visible (not visible on test results)

* Nyquist frequency defined as the highest spatial frequency where the CCD can still faithfully record
image detail. Beyond the Nyquist frequency aliasing occurs.

Impressive results, despite its lower resolution the F505V put in an excellent performance, matching the Coolpix 990 but not quite outdoing its Carl Zeiss clad family member the S70.

Red Channel Noise

When we first started reviewing the new batch of 3 megapixel digital cameras we noticed visible noise on flat blue areas, this turned out to be in the red channel and was thus dubbed "Red Channel Noise", we can see this as information in the red channel where there shouldn't be any. The samples below are of 50 x 50 blocks cropped from the colour comparison charts above of the Blue and Cyan patches, each block is then broken down into it's red green and blue channels and reflected as such directly beneath.

Well, no shocks here, the F505V producing almost identical results to the S70, we know that all three cameras share the same imager and the S70 & F505V probably share the same internal DSP and algorithms. At least Sony have got the red channel noise problem under control, this really lets the 990 down at times.