The D300S features a revised version of the implementation from the D300. The whole system is still far from seamless, whether you're in Tripod mode, with its slow, sensor-based contrast detect autofocus or Hand-held mode with the mirror flipping and screen blackouts that using the conventional DSLR phase detection AF sensor requires. That said, there aren't any cameras at this level that offer a significantly superior experience (the high watermark for live view is currently Panasonic's G series of cameras, which doesn't include anything approaching a semi-pro model), and the level of manual focus precision available will be a huge benefit to anyone shooting with a tripod.
Live view (auto focus) mode
Unlike previous Nikons, the D300S can continue to use its contrast detection autofocus when in movie mode (accessed from live view mode). It's not agonizingly slow but still not quick enough for focusing on moving subjects. The four screens available in each mode are essentially the same, but the view in Hand-held mode more closely resembles the view through the camera's viewfinder, with the limits of the focus points displayed on the screen. Move your mouse over the 'Tripod mode' tab to see how the views change in that live view mode.
|Default live view display||Live view without information|
|Live view with grid lines||Live view with level gauge|
Live view magnification
Probably the most useful application of live view on most DSLRs is the ability to zoom in on the preview to achieve and confirm perfect manual focus. Pressing the magnifying glass button zooms in, just as it would in playback mode. This is particularly good when combined with the contrast detection AF that is available in 'Tripod' live view mode - you can move your focus point around more freely than the 'Hand-held' mode that constrains you to the AF-sensor's 51 points.
Using contrast detection AF not only means that the screen doesn't black out but on the D300S also allows you to maintain the level of live view magnification, so you can watch the camera focusing exactly where you want it to. There are seven zoom steps, with the most magnified representing a 1:1 view.
Live view focus, magnify and exposure video clip
This video demonstrates contrast detection in Tripod-mode live view on the D300S using the Nikkor 16-85mm F3.5-5.6G VR. At the start of the video, the lens has been set to focus at infinity. Around one second into the video, the AF-ON button is pressed to initiate contrast-detection autofocus and the red autofocus area disappears. This is completed 3.5 seconds later when the camera shows exposure simulation again (the preview darkens slightly).