The HX100V sports a surprisingly powerful built-in flash, with a guide rating of 12.7m at ISO 100; nearly twice the range of many cameras in this class. We've found that at close range, the flash has a habit of 'overcooking' exposures, but flash exposure compensation is available.

Hand-held Twilight mode

In low light, where using a tripod isn't possible and using a noisy high ISO setting might not be desirable, the HX100V's Hand-held Twilight mode could come in handy. Another mode that takes advantage of the HX100V's fast continuous shooting capabilities, hand-held twilight functions by taking a series of images in rapid succession, then blending them into a single image.

The reason for doing this is that high ISO noise is a random phenomenon and as such, is found in a different pattern in each frame. By combining these frames it is possible to 'average' the noise, while preserving the definition of the fixed scene elements.

As you can see in the examples below, hand-held twilight mode significantly reduces the appearance of image noise, without sacrificing sharpness (assuming your subject doesn't move). It is an automated mode though, and as such you do not have control over exposure parameters. In this scene, shot under artificial light, the image shot with hand-held twilight mode is significantly 'warmer' than the conventional capture. We have not seen the same effect replicated in other shooting conditions.

P mode, Auto WB, ISO 2000, 1/40 @ f2.8 Twilight mode, ISO 800*, 1/15 @ f2.8
Program mode 100% Crop Twilight mode 100% Crop
Program mode 100% Crop Twilight mode 100% crop

It's obvious just how much more detail becomes visible with the smoothing of image noise and reduction in artifacts. The newspaper text is clearly more legible in hand-held twilight mode, which was captured at a nominally slower shutter speed.

* While it's reasonable to assume that twilight mode uses a lower ISO, the fact that multiple exposures are captured and blended together means that the reported ISO value is not necessarily accurate (it certainly isn't useful).

Overall Image Quality/Specifics

The overall image quality of the HX100V is quite good. Colors are reproduced in a reasonably accurate manner and contrast is pleasing at the camera's default settings. The HX100V's 16MP sensor holds up very well against much of its compact superzoom competition. There are, understandably, clear differences in image quality between the HX100V's base ISO of 100 and its maximum ISO of 3200. As the ISO increases, artifacts become more pronounced and at ISO 3200 color accuracy suffers, as saturation noticeably decreases. To be fair, the high ISO performance you see here is actually quite good in comparison to most 1/2.3" sensors. The HX100V's 16MP sensor manages to display a fair amount of image detail at its highest ISO setting.

This still life was shot at two different ISO settings with one stop of exposure compensation to lighten the background. The chief benefit of shooting at a lower ISO, particularly with small-sensor compact cameras is the lack of noise and artifacts.
ISO 100 (base ISO), 1/10 @ f5
ISO 800, 1/80 @ f5
ISO 3200 (max ISO), 1/320 @ f5