Overall Image Quality

As with the S70 the S75 has impecable colour reproduction, indeed, if anything colours are even stronger with the S75, a slim complaint with the S70 was the occasional undersaturation of what were accurate colours, this does appear to have been addressed. The only problem here is white balance handling which can at times be frustrating, under normal daylight automatic white balance is on the whole good, under incandescent or other types of artificial lighting it's not so good, luckily Sony have provided a "one-push" manual white balance mode which appears to work fairly well (but please, next time, more white balance options please).

As we'd expect the S75 is just as sharp and it's older brother the S70, with the same "Carl Zeiss" (I'll say it for sake of argument) lens and a similar (if not exactly the same) engine inside resolution, overall sharpness and image balance are all very good. If anything the S75 tends to produce a "flatter" image, performing less post-processing and preserving shadow detail a little more, this obviously means that you may need to tweak the images to give them "zing" on a monitor but it's far more preferable than having any of that detail destroyed by an over agressive in-camera contrast curve.

All in all the S75 strikes me as a camera for the photographer much more than the S70, lots of styling and ergonimic changes indicate this and so do some of the things Sony have "tweaked" at the image level.

Purple Fringing (Chromatic Aberrations)

The S75 does suffer from Chromatic Aberrations, as do all other cameras which use this lens system (and most other consumer 3 megapixel digital cameras), indeed for some reason the S75 I had for review (late pre-production) did seem to exhibit more "blooming" than I'd expect (the bright white halo which can run into dark areas of an image due to the overflow of charge from one photosite to the next) which tends to amplify the visual effects of chromatic aberrations).

Visible chromatic aberrations in an "every day shot"
Our now standard chromatic aberration test shot

Barrel and Pincushion Distortion

The S75 did quite well in our lens distortion tests, exhibiting the expected ~1% barrel distortion at full wide angle and about 0.2% pincushion distortion at full tele.

Barrel Distortion, 0.9% @ Wide Angle Pincushion Distortion, 0.2% @ Full Tele

White Balance

While things are better here with the addition of the one-push manual mode I'd still like to have seen more white balance options, the Indoor option doesn't work under any of our test artificial lighting, nor does the Outdoor option work on a cloudy day (you get a blue cast as seen below).

Outdoors, Auto Outdoors, Outdoor Outdoors, Manual
Incandescent, Auto Incandescent, Indoor Incandescent, Manual

All that said, Kudos at least for the one-touch manual preset option which does indeed seem to work quite well in various lighting situations. *U

Dynamic Range

Dynamic range simply defines the range of light the camera is able to capture before it either loses detail in darkness (shadows for example) or blows out a highlight (edges of chromed metals are good examples of this). Most consumer digital cameras only have a 8-bit analog to digital converters, plus their CCD's are not built to have a particularly large dynamic range, Sony report the S75 as having a 14-bit ADC.

Using our new dynamic range measurement method we measured the S75's dynamic range as (higher numbers are better except for noise):

Camera ISO Noise Range Bits Density dB

Sony DSC-S75
Native JPEG

100* 0.22 409:1 8.7 2.6D 52
100 0.22 409:1 8.7 2.6D 52
200 0.35 253:1 8.0 2.4D 48
400 0.73 164:1 7.4 2.2D 44
* In-camera sharpening set to "-2"

These results are impressive, easily as good as the best 3 megapixel consumer digital cameras and even significantly better at higher sensitivities (ISO) as we'd seen in the image quality comparison we'd carried out earlier. Defintely noise levels are down, interestingly results weren't any better with the in-camera sharpening disabled. *U