Timings & File Sizes

The EXILIM EX-Z3 is a surprisingly fast digital camera. Power on times are very quick, taking just over two seconds from the instant you press the power button. The camera's auto focus should also be praised it was very quick, especially if the subject distance was approximately similar to the last shot, in this instance AF takes around half a second. This gives the EX-Z3 a much more instant feel than most digital cameras, anyone switching from compact film to the EX-Z3 would notice no appreciable difference in shutter lag.

Timing Notes: All times calculated as an average of three operations. Unless otherwise stated all timings were made on a 2048 x 1536 Fine JPEG image (approx. 1,500 KB per image). The media used for these tests was a 128 MB SanDisk SD card.

Action	Details	Time, seconds
Power: Off to Record	Lens extension	2.1
Power: Off to Play	Image displayed	1.5
Power: Record to Off	Lens extended	1.9
Power: Play to Off	Lens already retracted	1.0
Mode: Record to Play	Image displayed	0.7
Mode: Play to Record	Lens extended	0.5
Play: Magnify	To first magnification step	2.2
Play: Thumbnail view	Nine image displayed (3x3)	0.9

Action	Details	Time, seconds
Zoom from Wide to Tele	Full zoom from 35 mm to 105 mm (3 x)	1.5
Auto Focus LAG	Wide angle	0.5 - 0.8
Auto Focus LAG	Telephoto	0.5 - 0.8
Shutter Release LAG	Using Viewfinder	<0.1
Shutter Release LAG	Using LCD Monitor	0.1
Total LAG	Wide angle	0.5
Total LAG	Telephoto	0.5
Off to Shot Taken	Wide angle	2.8
Shot to Shot *1	Wide angle, 2048 x 1536 Fine JPEG	3.2
Shot to Shot *1	Wide angle, 1600 x 1200 Normal JPEG	2.6

Auto Focus LAG is (roughly) the amount of time it takes the camera to autofocus (a half-press and hold of the shutter release button), this timing is normally the most variable as its affected by the subject matter, current focus position, still or moving subject etc. This timing is an average.

Shutter Release LAG is the amount of time it takes to take the shot from the moment you fully depress the shutter release button, measured both as a time including auto focus and a time assuming you have already pre-focused by holding a half-press of the shutter release.

File Write / Display and Sizes

Timings shown below are the time taken for the camera to process and "flush" the image out to the SD card, the timer was started as soon as the shutter release was pressed and stopped when activity indicator LED beside the viewfinder stopped blinking. This means the timings also include the cameras processing time and as such are more representative of the actual time to "complete the task". The media used for these tests was a 128 MB SanDisk SD card.

The EX-Z3's 'Fine JPEG' mode generates fairly large files considering the three megapixel resolution. These larger files cost the performance of the camera from a write speed point of view, because it doesn't provide a 'next shot' shooting buffer you have to wait approximately four seconds before you can take the next shot. Take compression up to 'Normal JPEG' and that delay is reduced to approximately three seconds, which is acceptable for an ultra-compact. Playback is instant, indeed if you hold down the left or right buttons on the 4-way controller the camera scrolls through images at about 3 frames per second.

Low Light Auto Focus

This test is designed to measure the minimum amount of light under which the camera can still focus. The focus target is our lens distortion test chart (shown here on the right), camera is positioned exactly 2 m (6.6 ft) away.

Light levels are gradually dropped until the camera can no longer focus. This is carried out at both wide angle and telephoto zoom positions (as more light reaches the focusing systems with a larger aperture).

This test target is the optimum type of subject for most "contrast detect" AF systems (as it has a vertical line at its center), you should consider the results below the best you could expect to achieve.

Light intensity (Lux) = 2.5 x 2^EV (@ ISO 100), 10.76391 Lux = 1 foot-candle (fc)

Rather surprisingly the EX-Z3 focused at both wide and telephoto focal lengths at the same light levels, despite the smaller aperture (thus less light) at telephoto. For a camera without an AF assist lamp this was a good performance, especially at the telephoto end of zoom.

Battery life

We ran the camera through our new battery life test. This test is designed to be fair and comparative to each camera and battery type:

• Take 4 shots without flash
• Wait 2 minutes (50% of the time powering the camera off)
• Take 1 shot with flash
• Wait 1 minute
• Repeat

Batteries are fully discharged and recharged before the test and all cameras were reset to their factory default settings. Here are the results:

The Casio EXILIM EX-Z3 takes the prize for the longest lasting camera on a 2.5/2.6 Wh capacity battery. The camera lasted an amazing 2 hours and 48 minutes in our battery life test notching up no less than 285 shots, this is a truly superb performance the only similarly powered camera anywhere near it is the Pentax Optio S.