Timings & File Sizes

The performance of the DX4900 was pretty much a mixed bag. Power on / off timings were average for this kind of camera (extending lens). Auto focus was surprisingly fast with an average AF time of around three quarters of a second (fast by digital camera standards) and sometimes even faster at wide angle with good light. Unfortunately this good AF performance was let down by a badly lagged LCD live view display and a longer than usual shutter release lag.

Also slow was image writing. This appeared to be a combination of a slow CF interface and limited internal processing power. It took notably longer to shoot and store lower resolution images than higher (see lower down this page).

Timing Notes: All times calculated as an average of three operations. Unless otherwise stated all timings were made on a 2272 x 1712 Fine JPEG image (approx. 850 KB per image). The media used for these tests was a 256 MB Viking CF card.

Action Details Time, seconds
Power: Off to Record Lens extends 4.7

Power: Off to Play *1

Image displayed 3.0
Power: Record to Off Lens retracts 2.7
Power: Play to Off *1 Lens already retracted 0.5
Mode: Record to Play Image displayed 0.5
Mode: Play to Record   2.3
Play: Image to image 2272 x 1712 Fine <0.5

Action Details Time, seconds
Zoom from Wide to Tele Full zoom from 35 mm to 70 mm (2 x) 1.8
Auto Focus LAG Wide angle (35 mm) *1 0.5 - 0.8
Auto Focus LAG Telephoto (70s mm) *1 0.8 - 1.1
Shutter Release LAG Using viewfinder 0.2
Shutter Release LAG Using LCD monitor *2 0.4
Total LAG Using viewfinder *3 ~0.9
Total LAG Using LCD monitor *3 ~1.1
Off to Shot Taken 6.4
Shot to Shot Only for first two shots, after that >5 sec 3.8

*1 Add approximately 0.8 seconds for low light situations
*2 We were surprised by how large the LCD lag was, the timing includes any lag introduced by the LCD 'live view'.
*3 Depending on focus and light levels

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 after autofocus, this timing assumes you have already focused (half-pressed the shutter release) and now press the shutter release button all the way down to take the shot. This timing is an average.

Total LAG is the total time it takes (not just the two above added together) if you haven't pre-focused, that is no finger touching the shutter release button, press it all the way down in one movement, this new timing is how long it'd take if you were in one of those spur-of-the-moment situations. This timing is an average.

Continuous modes

The DX4900 has only one continuous shooting mode, 1224 x 816 (300 KB JPEG) @ 3.8 fps.

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

Wait before
next shot

Continuous 1224 x 816 3.8 fps 12 11.0 sec

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

File Write / Display and Sizes

Timings shown below are the time taken for the camera to process and "flush" the image out to the Compact Flash card, the timer was started as soon as the shutter release was pressed (shutter click was heard) and stopped when activity indicator on the LCD 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 256 MB Viking CF card.

Image Type Time to store
file size
Approx. no. on
16 MB CF Card
2448 x 1632 (4.0 mp) 17.1 ~850 KB 12
2448 x 1632 (4.0 mp high compr.) 16.1 ~380 KB 24
2160 x 1440 (3.1 mp) 22.5 ~730 KB 16
1800 x 1200 (2.2 mp) 19.1 ~450 KB 23
1224 x 816 (1.0 mp) 13.4 ~240 KB 46

*1 Timings taken with 'Instant Playback' disabled. With Instant Playback enabled you can add 2.5 seconds to these times.
*2 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.

The DX4900 is clearly struggling with its limited processing power. The noticeable effect of this is that (a) it takes a long time (compared to other 4 mp digital cameras) to write an image and (b) it takes LONGER for smaller images than for larger (because the processor has to 'down-sample' the image before it is saved). The DX4900's playback is virtually instant so we didn't need to time that.

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 DX4900 performed well in our battery test. Considering it only requires two AA batteries the DX4900 managed to keep going for almost two hours, putting in an almost identical performance to Sony's DSC-P71 which also takes two AA batteries.