Timings & File Sizes

The PowerShot S400 feels quick in use and never introduces significant delays to the user. Power On time is impressive consider the extending lens system, although there is an additional 0.7 seconds before the camera recognizes the power button press. Other operational performance such as menu navigation, FUNC menu settings changes and image magnification feel virtually instant. One nag however could be the image to image delay browsing in playback mode. The additional delay in AF Lag introduced by using AiAF should be noted, the camera does feel faster with AiAF disabled (center area AF only).

Timing Notes: All times calculated as an average of three operations. Unless otherwise stated all timings were made on a 2272 x 1704 Super-Fine JPEG image (approx. 1,600 KB per image). The media used for these tests was a 512 MB Viking CF card. Timings below with AiAF switched off (faster) unless otherwise noted.

Action Details Time, seconds
Power: Off to Record *1 Lens extension 2.1
Power: Off to Play Image displayed 2.4
Power: Record to Off Lens extended 2.3
Power: Play to Off Lens already retracted 0.8
Mode: Record to Play *2 Image displayed 2.5
Mode: Play to Record Lens extended 1.9
Play: Magnify To 10x magnification 1.0
Play: Thumbnail view   1.1

Action Details Time, seconds
Zoom from Wide to Tele Full zoom from 35 mm to 105 mm (3 x) 1.8
Auto Focus LAG Wide angle 0.7 - 1.0
Auto Focus LAG Telephoto 1.0 - 1.2
Auto Focus LAG Wide angle, AiAF On 0.9 - 1.1
Auto Focus LAG Telephoto, AiAF On 1.1 - 1.4
Shutter Release LAG Using Viewfinder <0.1
Shutter Release LAG Using LCD Monitor 0.1
Total LAG Wide angle 0.8
Total LAG Telephoto 1.5
Off to Shot Taken Wide angle 3.5
Shot to Shot Wide angle 1.5

*1 You need to hold the power button for 0.7 seconds before the camera starts to power up. This is to avoid accidental knocks of the power button. The timing shown for this measurement exclude this 0.7 seconds.
*2 The S400 appears to buffer an image once displayed in play mode. This means that if you return to play mode for a second time the display time is just half a second, compared to 2.5 seconds for the first display of a new image.

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.

Continuous modes

Just like the S45 the S400 has two different continuous drive modes. The first (Continuous) shoots at approximately 1.5 fps and displays each frame on the LCD monitor as it is taken. The second (Continuous H) shoots at approximately 2.5 fps but blanks out the LCD monitor while shooting.

The table below shows the results of our continuous shooting test, indicating the actual frame rate along with maximum number of frames and how long you would have to wait after taking the maximum number of frames before you could take another shot. The media used for these tests was a 512 MB Viking CF card.

Mode Image Type Frames per sec Max no. of frames *1

Wait before
next shot

Continuous 2272 x 1704 Super-Fine 1.43 fps 5 1.5 secs
Continuous 2272 x 1704 Fine 1.46 fps 9 1.6 secs
Continuous 1600 x 1200 Fine 1.35 fps 18 1.4 secs
Continuous 1024 x 768 Fine 1.46 fps 48 0.9 secs

*1 In a single "burst" (finger held down on shutter release)
*2 You can take a frame as soon as there is space in the cameras internal buffer (writing continues "in the background").

The S400 delivers good continuous shooting capability with an obviously fair sized buffer. Overall a very good performance for the class of camera.

File Write / Display and Sizes

Timings shown below are the time taken for the camera to process and "flush" the image out to the CF 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 512 MB Viking CF card.

Image Type Time to write

Time to display
File size *1
Images on a *2
512 MB CF
2272 x 1702 Super-Fine JPEG 2.8 1.8 1,600 KB 247
2272 x 1702 Fine JPEG 2.3 1.3 950 KB 442
1600 x 1200 Fine JPEG 1.8 0.8 480 KB 879
1024 x 768 Fine JPEG 1.4 0.6 220 KB 1522

*1 All file sizes are an average of three files. As is the case with JPEG it's difficult to predict the size of an image because it will vary a fair amount depending on the content of the image (especially the amount of detail captured). For example, take a photograph of a fairly empty wall and you'll get a small JPEG, take a photograph of a bush with a lot of detail and you'll get a larger image. File sizes here are closer to the later, the larger size of file you should expect.
*2 Camera estimation.

Fairly fast write times considering the file size and the product category. The camera also has a good buffer system which allows you to get on with taking the next shot while it continues to process / write the last shot in the background.

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.

Lens position AF Assist Aperture Lowest light focus
Wide angle (36 mm) On F2.8 1.1 EV (5.4 Lux, 0.50 foot-candle)
Telephoto (108 mm) On F4.9 2.5 EV (14.1 Lux, 1.31 foot-candle)
Wide angle (36 mm) Off F2.8 1.4 EV (6.6 Lux, 0.61 foot-candle)
Telephoto (108 mm) Off F4.9 2.5 EV (14.1 Lux, 1.31 foot-candle)

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

The S400 produce a virtually identical performance with or without its AF assist lamp, this could be due to the fact that at least on our camera the AF assist lamp did not hit the center of the target, rather it was aligned lower than the center area of the scene frame.

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:

Compact / Ultra compact
Battery Power Battery life Number of shots
Kyocera S3 BP-800S 2.1 Wh 54 mins 95
Canon PowerShot S300 NB-1L 2.5 Wh 1 hr 26 mins 155
Pentax Optio 430 D-LI2 3.3 Wh 1 hr 33 mins 160
Olympus C-40Z 2 x AA NiMH 1600 mAh (GP) 3.6 Wh 1 hr 33 mins 165
Nikon Coolpix 3100 2 x AA NiMH 1600 mAh (GP) 3.6 Wh 1 hr 42 mins 175
Minolta DiMAGE F100 2 x AA NiMH 1600 mAh (GP) 3.3 Wh 1 hr 42 mins 175
Minolta DiMAGE X NP-200 2.8 Wh 1 hr 45 mins 180
Pentax Optio 330 D-LI2 3.3 Wh 1 hr 48 mins 185
Canon PowerShot S330 NB-1LH 2.5 Wh 1 hr 48 mins 185
Sony DSC-P71 2 x AA NiMH 1600 mAh (GP) 3.6 Wh 1 hr 50 mins 185
Kodak DX4900 2 x AA NiMH 1600 mAh (GP) 3.5 Wh 1 hr 51 mins 190
Sony DSC-P5 NP-FC10 2.4 Wh 1 hr 51 mins 190
Nikon Coolpix 3500 EN-EL2 4.1 Wh 1 hr 54 mins 195
Sony DSC-P9 NP-FC10 2.4 Wh 1 hr 59 mins 200
Nikon Coolpix SQ EN-EL2 3.7 Wh 2 hr 03 mins 210
Minolta DiMAGE Xt NP-200 2.8 Wh 2 hr 12 mins 225
Canon PowerShot S400 NP-1LH 2.5 Wh 2 hr 17 mins 230
HP Photosmart 812 2 x AA NiMH 1600 mAh (GP) 3.6 Wh 2 hr 21 mins 240
Nikon Coolpix 885 EN-EL1 4.8 Wh 2 hr 21 mins 240
Nikon Coolpix 775 EN-EL1 4.8 Wh 2 hr 27 mins 250
Canon PowerShot SD100 NB-3L 2.9 Wh 2 hr 29 mins 250
Pentax Optio S D-LI8 2.6 Wh 2 hr 33 mins 260
Nikon Coolpix 2500 EN-EL2 4.1 Wh 2 hr 33 mins 260
Fujifilm FinePix F601Z NP-60 3.7 Wh 2 hr 47 mins 275
Casio EXILIM EX-Z3 NP-20 2.5 Wh 2 hr 48 mins 285
Casio EXILIM EX-S3 NP-20 2.5 Wh 2 hr 48 mins 285
Olympus C-50Z LI-10B 4.0 Wh 2 hr 54 mins 295
HP Photosmart 935 2 x AA NiMH 1600 mAh (GP) 3.6 Wh 3 hr 09 mins 320
Canon PowerShot A70 4 x AA NiMH 1600 mAh (GP) 7.7 Wh 5 hr 08 mins 515
Other test notes:
 • LCD monitor is left on during the battery test
 • The camera is powered off half of the time and left on half of the time (switch every 10 iterations)
 • There are now higher capacity AA NiMH batteries available, however in the interests of fair
    comparison we will continue to use our 1600 mAh test set

The PowerShot S400 managed to last 30 minutes longer than the S330 using the same 2.5 Wh NP-1LH battery pack. This is a good performance for such a small, relatively low capacity battery. Clearly Canon's claims about power savings with their DiGiC processor are accurate.