Canon PowerShot A70 Review
Top of camera controls
The top of the A70 has three control groups, firstly the on/off button, this requires a short hold before the camera will power on, power off is instant. The mode dial overhangs the rear of the camera slightly making it relatively easy to change mode, the action of the dial is just stiff enough so as not to suffer accidental change. At the front you can see the zoom lever and shutter release button.
Zoom Lever (Record mode)
Zooms the camera's lens towards the telephoto, maximum optical zoom of 105 mm (35 mm equiv.). A full zoom from wide to tele takes 2.0 seconds. There are 7 zoom steps from wide angle to telephoto. If the camera is already at maximum optical zoom and digital zoom is enabled the camera will apply increasing levels of digital zoom (indicated on the LCD monitor).
|Zoom wide angle
Zooms the camera's lens towards the wide angle of 35 mm (35 mm equiv.). A full zoom from tele to wide takes 2.0 seconds. There are 7 zoom steps from telephoto to wide angle.
Zoom Lever (Play mode)
|Image magnify (zoom
Magnifies the displayed image, a range of magnification is available from 2x up to 10x. Magnifying the displayed image is very fast.
/ (zoom out)
Switches to a 3x3 (9 image) thumbnail index, use the four direction buttons on the rear of the camera to move around the index. If the displayed image is magnified pressing the zoom lever towards wide zooms out of the magnification.
Camera has complete control over exposure, point-and-shoot operation, the majority of manual features are disabled, you can't alter white balance, exposure compensation, ISO, metering or use manual focus. You can set flash mode, drive, macro focus and image size.
Program Auto Exposure
Shutter Priority Auto Exposure
Aperture Priority Auto Exposure
Full Manual Exposure
In this mode apertures are kept as large as possible (small F number) to produce a blurred background to help define the subject in a portrait shot. Note: Macro and manual focus are available in Portrait mode.
In this mode the flash is by default disabled (although you can enable it) and focus is locked at infinity. Apertures are kept as small as possible (large F numbers) to produce the largest possible depth of field. Manual focus is available. Designed to be used for taking landscape shots.
Known on other cameras as "Slow Sync Flash". Put simply in this mode slow shutter speeds are used to capture a dimly lit background (buildings at night for example) and the flash fires briefly to illuminate a foreground subject.
Instructs the camera to uses the fastest possible shutter speed for a particular exposure, this often means the largest aperture (F2.8 at Wide, F4.9 at Tele) in combination with ISO 100. Useful for capturing sports events.
Instructs the camera to uses the slowest possible shutter speed for a particular exposure, this often means the smallest aperture F8.0. Useful for blurring moving water.
Designed to make shooting of panorama / stitch shots easier. You have a choice of five different stitch modes: left-right, right-left, down-up, up-down or 4-frames in a square. The display changes to show previously shot frames in the sequence to help alignment of each frame. Exposure and White Balance are locked to the first frame.
Record short movie clips, you can not zoom during movie recording and the exposure is locked from the moment you start recording.
640 x 480, 15 fps, up to 30 secs (inc. audio)
320 x 240, 15 fps, up to 3 mins (inc. audio)
160 x 120, 15 fps, up to 3 mins (inc. audio)
* Aperture / Shutter speed rule
Just like other PowerShot's (and many other digital cameras) the A70 is limited by the fact that it uses a single iris mechanism for both aperture and shutter. The iris opens at the beginning of the exposure to a certain size for the selected (or metered) aperture and then closes again at the end of the exposure. The speed at which the iris can go from a wide aperture to completely closed creates a limitation as to the maximum shutter speed available at different apertures.
|Zoom position||Aperture||Max. Shutter Speed|
|Wide angle||F2.8||1/1250 sec|
|F3.2 - F4.0||1/1600 sec|
|F4.5 - F8.0||1/2000 sec|
|F5.6 - F7.1||1/1600 sec|
|Thunderheads With Egret by Buzz Lightyear|
|Double Rainbow; Abiquiu, NM, USA. by abiquiuense|
from After the Rain
|White Tern-2289 by vbuhay|
from A Whiter Shade of Pale