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Canon PowerShot A40
"Picky Details" for the Canon PowerShot A40 digital
camera
(Timing, Power, and Storage Info)
Timing
I measure both cycle times and shutter delay times, using a proprietary Imaging
Resource test system. Here are the numbers I collected for the Canon PowerShot
A40:
|
Canon PowerShot A40 Timings
|
|
Operation
|
Time
(secs)
|
Notes
|
| Power On -> First shot |
3.13
|
About average for a camera with a zoom lens.
|
| Shutdown |
4.4
|
Average to a little slower than average.
|
| Play to Record, first shot |
2.7
|
Time until first shot is captured. About average.
|
| Record to play |
2.0
|
Time to display a large/fine file after capture. Pretty
fast.
|
| Shutter lag, full autofocus |
0.86/1.36
|
First time is for wide angle zoom setting, second
is for telephoto. Wide angle time is about average, tele time is a bit
slower than average. |
| Shutter lag, prefocus |
0.09
|
Time to capture, after half-pressing shutter button.
Very fast!
|
| Cycle Time, max/min resolution |
2.2-2.4/2.1
|
First numbers are for large/fine files, second number
is time for small/basic images. Very fast. There may be a buffer memory,
as the first three shots generally came in with cycle times around 2.2
seconds, subsequent ones averaged 2.4, but even the 2.4 is quite fast. |
| Cycle Time, continuous mode, max/min resolution |
1.24-0.83
0.91- 0.65 (1.2/1.5 fps)
|
First pair of numbers is for large/fine, second set for small/basic
files. Numbers beneath are corresponding frames per second. Quite fast.
Seven large/fine frames before pausing, 63 small/basic ones. Oddly, delay
between first two frames is longer than between subsequent ones. (1.24
vs 0.83 for large/fine, 0.91 vs 0.65 for small/basic.) |
The PowerShot A40 is average to somewhat faster than average, depending on
the parameter you're looking at. Startup and shutdown times are about average.
Shutter lag in full autofocus is average at wide angle, a bit slower than
average at telephoto. Prefocus shutter delay is blazingly fast though, at
only 90 milliseconds. Cycle times are very good, a bit over two seconds for
both large/fine and small/basic files. Continuous mode cycle times are also
quite good for a more or less entry-level camera.
Power
The PowerShot A40 uses four AA cells for its power source, and displays
good to excellent battery life. (Provided that is, that you use high-capacity
NiMH cells, coupled with a good charger. Read my NiMH
Battery Shootout page for the latest on actual battery performance, or my
review of the
Maha C204F to see why it's my favorite charger.)
As noted, the A40's battery life is very good overall, and exceptional when
you run it with the LCD screen turned off. - You could confidently leave it
on all day with the LCD turned off, and have well over half your original battery
charge left by evening. Even in its worst-case power consumption mode (capture
mode with LCD turned on), it should run for well over three hours on a set of
high-capacity NiMH batteries. The table below shows the A40's power consumption
in various modes, and approximate run times for each, based a set of NiMH batteries
with a (true, not advertised) 1600 mAh capacity:
|
Operating Mode
|
Power
(@4.3 volts on the external power terminal)
|
Est. Minutes
(4 1600 mAh NiMH cells)
|
| Capture Mode, w/LCD |
501 mA
|
214
|
| Capture Mode, no LCD |
85mA
|
(~20.9 hours)
|
| Half-pressed shutter w/LCD |
514 mA
|
209
|
| Half-pressed w/o LCD |
343 mA
|
313
|
| Memory Write (transient) |
503 mA
|
n/a
|
| Flash Recharge (transient) |
1040 mA
|
n/a
|
| Image Playback |
290 mA
|
369
|
Overall, really good battery life for a fairly compact camera.
Storage Capacity
The PowerShot A40 stores its photos on CF (CompactFlash) memory cards, and
an 8 MB card is included with the camera. (I strongly recommend buying
at least a 16MB card, preferably a 32 MB one, to give yourself extra space for
extended outings. - Heck, these days memory cards are so cheap, there's no reason
not to get a 64 MB card, which could store 65 images at maximum size and quality!)
The chart below shows how many images can be stored on the included 8 MB card
at each size/quality setting.
Image Capacity vs
Resolution/Quality
8 MB Memory Card
|
Super
Fine
|
Fine
|
Normal
|
| Full
Resolution 1600x1200 |
Images
(Avg size) |
8
973 KB |
12
623 KB |
25
313 KB |
Approx.
Compression |
6:1 |
9:1 |
18:1 |
| XGA
Resolution 1024x768 |
Images
(Avg size) |
17
462 KB
|
26
305 KB
|
48
165 KB
|
Approx.
Compression |
5:1
|
8:1
|
14:1
|
|
VGA Resolution 640x480
|
Images
(Avg size) |
36
217 KB
|
52
152 KB
|
90
88 KB
|
Approx.
Compression |
4:1
|
6:1
|
10:1
|
Download Speed
The PowerShot A40 connects to a host computer via a USB interface. Downloading
files to my 500 MHz PowerMac G4 (OS 9.1), I clocked it at 417 KBytes/second.
This is a fairly typical figure. (Cameras with slow USB interfaces run as
low as 300 KB/s, cameras with fast ones run as high as 600 KB/s.)
|