Here you can see a generated GretagMacbeth ColorChecker chart, place your mouse over any of the labels below it to see the color reproduction in that mode. Select a camera/setting combination from the 'Compared to' drop-down to comparative boxes inside each patch.
The A900's default setting delivers results that are noticeably 'punchier' than you'd get from, for example, the Nikon D700, though the difference isn't really in color response (hue) - it's just a matter of Sony choosing to go for a more saturated look. That said, the A900's huge number of preset image 'Creative Styles' provide a wide range of canned color and tone responses and the 'Neutral' preset is probably the closest it gets to what we'd normally expect to see from a camera at this level.
Artificial light White Balance
Another digital SLR, another disappointing result from the auto white balance in artificial light. If you want neutral colors you'll need to get out a grey card and use custom WB. Even the preset WB options on the A900 don't do a particularly good job at hitting the right color temperature.
Incandescent - Auto WB
Red: 16.2%, Blue: -24.9%, Very Poor
Incandescent - Incandescent preset WB
Red: 4.3%, Blue: -8.6%, Average
Fluorescent - Auto WB
Red: 13.4%, Blue: -23.2%, Poor
Fluorescent - Fluorescent preset WB
Red: 5.8%, Blue: -9.6%, Average
The Alpha 900 has no built-in flash but is compatible with all Minolta and Sony dedicated flash units. In our tests using the new HVL-F58 unit we found exposure to be very accurate indeed and the color to have a very slight warm tone by default (this is usually a good thing when using flash for portraits).
Sony HVL-F58 Direct Flash
Sony HVL-F58 Bounce Flash
Sony HVL-F58 Direct Flash
Overall Image Quality / Specifics
I have to say that up to ISO 800 the Alpha 900 produces very pleasing results indeed; metering/exposure is simply superb, highlight clipping incredibly well controlled and although using the default settings the color is perhaps a little over-vivid (we found some red clipping on bright days) it is very 'consumer friendly' and can of course be customized using the Creative Styles.
If you look too closely at the files you'll see that the JPEG engine produces a slight smearing of very fine low contrast detail (losing individual blades of grass in a wideangle lawn shot, for example), but we really are at an almost ridiculous level of pixel peeping here; besides which you can eke a little more detail from the sensor by shooting raw and developing using Adobe Camera Raw. Unless you're only looking for modest enlargements I'd also recommend shooting in raw mode when using the higher ISO settings as the in-camera noise reduction has a strongly detrimental effect on fine detail (noise unarguably being this camera's achilles' heel).
Of course a 24MP full frame sensor is going to need some very high quality glass in front of it to really shine, and you'll need to budget for some pretty serious lenses if you want to get the most from the Alpha 900. A sensor this large and with such high resolution is going to be unforgiving of older or cheaper lenses and will, if you look too closely, reveal all their imperfections (soft edges, chromatic aberration, lack of resolution) for all to see. That said, once again you need to be going for some serious enlargements before this becomes an issue (and this is far from being a problem for this camera alone).
Overall there's really little to complain about here - and much to like - and I'd only caution concern if you regularly intend to shoot at ISO 1600 or higher. 100% comparisons are a valid and useful way to check out the absolute limits of a camera's resolving power, but in my book the superb tonality, appealing color and surprisingly reliable metering / focus systems count for a lot and mean the Alpha 900's output at lower ISO settings is amongst the best we've seen.