Timings & File Sizes

There are some functions of this camera which can feel almost normal, such as power up which although slow wasn't that much different to many other extending lens cameras. Off to shot taken and shot to shot times were average to below average. Where the HP really suffers is in its image processing and SD storage communication, both of which appear to be exceedingly slow. For example magnifying an image in play mode takes over five seconds, storing a full resolution average quality image in record mode takes over twelve seconds. Performance and responsiveness (the 'feel' of the camera) are both issues HP need to address.

Timing Notes: All times calculated as an average of three operations. Unless otherwise stated all timings were made on a 2608 x 1952 JPEG image (approx. 2,300 KB per image). The media used for these tests was a 512 MB Viking SD card.

Action Details Time, seconds
Power: Off to Record Lens extension 4.5
Power: Record to Off Lens extended 3.7
Mode: Record to Play *1 Image displayed 1.2
Mode: Play to Record   0.5
Play: Magnify To 4x magnification 5.3

Action Details Time, seconds
Zoom from Wide to Tele Full zoom from 37 mm to 111 mm (3 x) 1.5
Auto Focus LAG Wide angle 0.8 - 1.2
Auto Focus LAG Telephoto 1.1 - 1.4
Shutter Release LAG Using Viewfinder 0.1
Shutter Release LAG Using LCD Monitor 0.2
Total LAG Wide angle 1.1
Total LAG Telephoto 1.1
Off to Shot Taken Wide angle 4.6
Shot to Shot Wide angle 2.3

*1 Al portion of this time (approximately 0.5 seconds) is taken up by the LCD screen 'powering up'.

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 CF card, the timer was started as soon as the shutter release was pressed and stopped when activity indicator LED above the SD compartment 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 SD card.

Image Type Time to write

Time to display
File size *1
Images on a *2
512 MB SD
2608 x 1952 JPEG 14.5 <0.5 2,300 KB 196
2608 x 1952 JPEG 12.5 <0.5 1,100 KB 392
1296 x 976 12.2 <0.5 900 KB 392
1296 x 976 11.5 <0.5 500 KB 838

*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.

Pretty appalling really, no camera should take fourteen seconds to store a 2 MB JPEG. Looking down the figures you will note that the times change very little as the image dimensions and file size drop, this hints that the bottleneck is in HP's image processor rather than the actual SD interface. We repeated the above test with various SD cards of different capacities and from different manufacturers and got the same results +/-2%. Consider that Pentax's Optio 550 (not a quick camera by anyones standards) takes just five seconds to process and store a similarly sized file (to an SD card).

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 Aperture Lowest light focus
Wide angle (37 mm equiv.) F2.6 2.8 EV (17.4 Lux, 1.62 foot-candle)
Telephoto (111 mm equiv.) F4.6 2.4 EV (13.2 Lux, 1.23 foot-candle)

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

Without an AF assist lamp the HP 935 struggled to focus without some moderate lighting, and indeed performed better zoomed in closer to the center of the AF target than at wide angle.

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

Thanks to its aggressive power saving the HP 935 lasted over three hours on just two 1600 mAh AA batteries. This is a very good performance and goes a long way to supporting the relatively short LCD on time (just 60 seconds).