Manual focus and focus aids
Direct Manual Focus
The RX1 has two methods of combining Autofocus with Manual focus, with the main difference being which is seen as the primary focus method. The main one is Direct Manual Focus - a mode that fits between Autofocus and Manual focus both on the camera's control dial and in the way it operates.
DMF mode allows you to adjust focus manually after the camera has autofocused. In this mode, all the AF point selection methods except AF Tracking are available then, if the shutter button is held in the half-pressed position, turning the focus dial will allow manual focus.
There is an alternative method for accessing autofocus from manual focus mode, though. Setting either the 'C' or 'AEL' buttons to 'AF/MF Control Hold' results in the camera performing an AF-S acquisition from manual focus mode when you press the desired button.
Manual focus operation:
The physical behavior of manual focus mode is very pleasant, with a well damped focus ring giving a nice feel to proceedings. The focus behavior is speed-sensitive, so you have to be careful not to be too subtle with the ring unless you're already nearly in focus. Such programming has to strike a fine balance between giving the ability to quickly get to the right focus region and providing fine control at sensible speeds when you get there. Overall the RX1 puts a little more emphasis on the second requirement, which makes sense for a camera with such potentially shallow depth-of-field at close focusing distances.
While you manually focus, a distance scale appears at the bottom of the screen (except in movie mode), to give you an indication of how far through the focus range you are. The scale gives no indication of depth-of-field, however. Beyond this, there are two further focus aids to help with manual focus speed and accuracy: magnified live view and focus peaking.
The main manual focus aid is magnified live view (MF Assist in Sony parlance) which zooms in to give a 5.9x magnification of the center of the frame in MF mode or the selected AF point in 'DMF' mode. Pressing the center button causes the camera to zoom in to 11.7x magnification for high precision work, while the two dials can be used to move the position being magnified.
The amount of time for which the magnified view persists can be adjusted in the camera's menus. There are options for 2 seconds, 5 seconds or unlimited. The unlimited mode gives you time to position the magnified area and switch between magnification levels. It's worth being aware that, while in MF mode you can quickly half-press the shutter button to revert to an unmagnified view to check your composition, this isn't possible in DMF mode - releasing the shutter ensures another AF sequence will lose the focus you've just achieved.
|This image shows the 5.9x magnified view for accurate manual focussing.
Pressing the center button on the four-way controller zooms in again to 11.7x for really critical focus.
The other manual focus confirmation method offered by the RX1 is focus peaking - only available from within a magnified view. This highlights the highest-contrast edges in the scene - giving a clear and quick understanding of what's in focus. Focus peaking can be set to any of three colors and three intensities to ensure visibility against your subject. The only downside is that it can become indistinct in low light situations, where the camera struggles to discern contrast in the scene.
|Pressing the center button magnifies the view further (to 11.7x).
Here we've simulated the effect of focus peaking, which highlights high-contrast edges.
It's a useful tool or would be, if it could be accurately used in full-screen mode.
Sadly, the VGA screen on the RX1 doesn't allow precise enough rendering of focus peaking to ensure accurate focus with the F2 lens' shallow depth-of-field, so focus peaking is only available in magnified focus. This is rather disappointing, since one great value of focus peaking is the ability to manually focus quickly while also viewing your shot's composition. Our experiments with Focus Peaking with wide aperture lenses on the NEX system support Sony's decision to remove this feature, but it is a shame it could not be made to work accurately.