Sony's latest Single Lens Transparent ('SLT') camera - the Alpha A55 - adds GPS and a super-fast 10fps burst rate. Is the Sony A55 the dawn of a new digital camera revolution?
Sony Alpha A55 Review
Movie/Video Mode & Quality
Sony Alpha A55 review – Movie/Video Mode & Quality
Sony A55 review – Movie/Video Quality
When shooting in AVCHD final movie quality is very impressive indeed. Although clips are shot in a 1920×1080 pixel interlaced format (i.e. half the lines in one pass, the other half in the second pass), the level of detail is still very impressive and the data rate is a massive 74Mbit/sec. One small issue is when not using a formatted card it will become nigh-on impossible to extract your files from the camera (as AVCHD files have to be processed using software such as iMovie or Windows Movie Maker).
There is a secondary option to shoot in MP4, which is captured at 1440×1080 pixels and then ‘upscaled’ to fit the usual 16:9 ratio. The quality here is less impressive though, with a much lower data rate. However, the files are smaller and won’t need processing when offloading from camera.
Sony A55 review – Movie/Video Record Time
Maximum record time is up to 29mins or 2GB, though the AVCHD format is so packed full of data that you’ll only manage a few minutes before the largest file size is reached. This is the same for AVCHD 1080i, and MP4 AVC and VGA.
As a number of reports have suggested and Sony Japan itself has now confirmed, the sensor overheats when using SteadyShot while recording. This isn’t at all surprising given the amount of work the sensor is doing, and with a clip length topping out at around 7mins this is still a fairly long time to be able to shoot (how often would a longer clip length be utilised?).
Sony A55 review – Movie/Video Focusing Modes
Focusing during movie recording is where the A55 both wins and loses. On the one hand the continuous focus is outstandingly good and will effortlessly snap between one subject and the
next without misjudging focus at all.
The only qualm with this is the lack of overall user control, as there’s no capacity to lock the focus (bar clunkily flipping the lens’ AF/MF switch). Such a feature would be useful in some situations, for example when the camera is focused on
a stationary subject and another subject walks through the frame causing the camera to switch focus to the new subject. This won’t always be desired and a greater level of detail in control here would make all the difference. Many DSLRs and Micro System Cameras offer a one-touch button
to re-focus and this single-point fixed focus isn’t possible with the A55.
Sony A55 review – Movie/Video Manual Control
There’s no true fully manual control when shooting in movie mode, although the degree of control in Program mode should prove ample for most situations. During recording it’s possible to use both exposure compensation and exposure lock in real time, which can prove considerably useful. However, limitations with focus modes, aperture selection and a fixed 25fps frame rate mean there’s some room for improvement.
Sony A55 review – Movie/Video Sound
The kit lens can be rather noisy when whizzing between different focal lengths and the camera will pick up these sounds. Thankfully there’s
a 3.5mm mic jack for an external microphone
to be used should you please.
The sound quality is otherwise very good
(partly dependent on which mic you choose to
use) and rendered as AAC Stereo.