The X100's flash is underpowered by the standards of typical DSLRs, but to a great extent this is made up for by the camera's fast lens.

In this shot (taken at ISO 400 in aperture priority mode at f/5.6) the subject was positioned roughly 1.5m away from the camera. Color and exposure are good, and despite the proximity of the flash to the lens, there is no evidence of red-eye.

We took the above test shot at ISO 400 with automatic ISO control turned off, but it's worth knowing that if you turn on the flash when Auto ISO is enabled, the camera will meter and set its exposure (including sensitivity) based purely on the ambient lighting, and without considering the flash, until it reaches a light level so low that it has to start dropping the shutter speed below the minimum set in the Auto ISO program to achieve correct exposure. Only at this point will it use the flash as the main light source, rather than simply as fill.

Film simulation modes

The X100 provides a range of colour 'looks' that Fujifilm - playing on its rich analogue photography heritage - calls 'Film Simulation' modes. These consist of three colour modes, named after the company's professional slide films - Standard / Provia, Vivid / Velvia, and Soft / Astia - and a number of monochrome modes that aim to simulate the effects of using coloured filters with black-and-white film (yellow, red, green or no filter), plus a 'retro' Sepia-toned mode.

Standard/Provia Vivid/Velvia Soft/Astia Monochrome
Mono (Yellow Filter) Mono (Red Filter) Mono (Green Filter) Sepia

Curiously, the Standard / Provia mode is (in our opinion) the least appealing of the three colour options, mainly because if its very 'open' shadow tone curve that reduces perceived saturation and 'punch'. Vivid / Velvia certainly lives up to its name - we're not convinced that it provides exactly the same look as the iconic film it's named after, but it's certainly very vivid and saturated. Highlights tend to blow more easily, though, and we'd probably be tempted to dial the Highlight Tone down a notch. Astia, meanwhile, provides a very attractive middle-ground, with excellent rendition of skin tones in particular. Of the mono modes, we'd be most inclined to use the red filter mode for landscapes, and green filter for portraits.

The X100 offers a great deal of control over its JPEG processing; you can adjust the colour, sharpening and noise reduction, and even set the shadow and highlight tone (contrast) independently. However any changes you make to these settings are applied across all the film simulation modes, so it's not possible to tailor them each individually to you tastes. A workaround to this is to save any preferred tweaks to one of the three custom settings sets, which can then be recalled through the menus, but it's important to remember that these save ISO and DR settings too. It's also worth bearing in mind that if you shoot raw, you have free control over all these processing parameters when using the X100's in-camera raw development after shooting.

Large aperture / high shutter speed combinations in manual mode

One apparent oddity of the X100 is that, if you set the camera to aperture priority and F2 in bright sunlight, the camera will select 1/1000 sec and the image will come out overexposed. However, if you switch to manual mode and dial in a higher shutter speed, the image will often come out correctly exposed, while claiming to be shot at the selected settings in the EXIF (for example 1/4000 sec F2 ). Obviously, this makes no sense.

1/4000 sec F2 ISO 200, manual exposure 1/550 sec F2 ISO 200, with ND filter
100% crop 100% crop

If you look a little closer at the correctly-exposed image file, though, it becomes clear what's going on. The background blur is clearly less smooth than it should be, with odd triangular-shaped highlights. This is because the shutter is unable to uncover the full diameter of the aperture at this speed, but just a segment of it instead. As a result, the background blur is messy and unattractive. (It also follows that achieving a correct exposure here was essentially down to luck - the effective aperture just happened to let in the correct amount of light.)

To illustrate this more clearly, we shot an out-of-focus orange LED lamp at F2 and a range of shutter speeds; the lamp was placed in the center of the frame. This shows the shading effect of the shutter blades on the aperture opening very clearly; essentially you can see the blades pivoting outwards from the 8 o'clock position, and opening progressively further at slower shutter speeds. (Note that the crops below are taken from landscape format shots, and therefore rotated 90 degrees anticlockwise compared to the example above.)

1/4000 sec, F2 1/2000 sec, F2 1/1000 sec, F2 1/500 sec, F2

Interestingly this implies that even at 1/1000 sec (the fastest shutter speed allowed in A mode at F2) the shutter blades haven't quite cleared the aperture opening completely. Only at 1/500 sec do we see the full uninterrupted aperture opening. Overall, we're not sure it's a good idea for Fujifilm to allow these fundamentally incompatible settings to be used together in manual mode.