Casio EX-S770

Reviewed January 2007

Test Photos

STILL LIFE PHOTO

This subject is photographed in a room that has a mix of fluorescent and incandescent light, but which is not brightly lit. The camera's flash is used to add fill light. The backdrop is 1.95 m (6.5 ft) from the camera.

At the wide angle end of the zoom, the EX-S770 has an aperture of f2.7, large enough to allow for a bright image without having to adjust any of the camera settings.

But, while the image the S770 yields is bright, some noise is detectable as graininess, and the overall sharpness of the image appears to have been lowered by the compression.

ZOOM PHOTO

Now we zoom in on a specific area. The intent is to test the sharpness of the image at the zoom's maximum setting. The camera remains at the same distance as with the preceding photo.

At the telephoto setting, the brightest aperture available to the camera becomes f5.2, and the image is noticeably darker as the flash runs out of power. To overcome this, Casio has equipped the S770 with a special function called Flash Assist that processes the image to increase its brightness as soon as it is captured, and then saves the processed image.

MACRO PHOTO

With the Macro mode, the EX-S770 is able to focus on a subject between 15 to 50 cm (5.9 to 19.7 inches) from the front element of the lens at the wide angle end. This allows the camera to capture a field of view measuring approximately 12.5 cm (4.87 inches) horizontally.

That large a field of view is more in line with what is commonly described as a "close-up" than a macro shot. By the same token, the fact that the lens is not too close to the subject means that barrel distortion is minimal.

BUILDING PHOTO

This image is our outdoor test. The architecture of the building, in particular the angled girders, immediately show the presence of jaggies. The shadowed entrance can also often reveal the quality of the exposure.

Regrettably, while the Casio Exilim EX-S770 was here for review, the weather was consistently awful. These shots of our standard building are typical. Fog, mist and rain make photography with any camera very challenging, and invariably augment noise that would be invisible had the shot been captured with reasonably good ambient light.

Still, the EX-S770 yields an acceptable image, albeit with an increase in noise, that when printed at a 5 x 7 inch size is quite good.

ZOOM PHOTO

Zooming in on the entrance of the building, the shadowed entrance takes on a greater importance for the metering and can cause an overexposure of sections that are directly lit.

At the maximum telephoto setting, the lens has an even smaller maximum aperture and the camera's CCD receives even less light. The only solution is to allow the camera to increase the sensitivity of the CCD by setting it to Auto ISO, and accept that noise will become more visible.

Nevertheless, under these difficult conditions the EX-S770 managed as well as other cameras would have, especially as the shot is hand held.

NIGHT PHOTO

This camera is capable of long exposures, and an image captured late at night is presented to give an idea of its capabilities.

The Casio EX-S770 can capture its longest exposure when set to the Night Scene mode. By default, the mode sets the camera to Daylight white balance, sensitivity to 50 ISO, and the focus to infinity, but is limited to a maximum exposure of 4 seconds. To capture a night shot with these limits, the subject must be quite well lit.

As noted above, the weather over the review period for this camera was inclement, and nights shrouded in thick fog, forced the use of a relatively nearby and bright subject: a tug berthing area.

Left to its defaults, when confronted with this subject the EX-S770 elected to capture the subject at the widest aperture, f2.7, but with an exposure time of only 1 second. While a 1 second exposure is indeed sufficient to capture an image with a brightness comparable to what the human eye perceives, it is also a relatively dark and uninteresting image. To fool the metering into increasing the exposure time, partially obscuring the lens while pressing the shutter release halfway made it possible to get the camera to capture images at 2 or 4 seconds — depending on how much the lens is obscured — without affecting the sharpness since the focus is automatically set to infinity.