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The camera is controlled by two dials. The mode dial is located on top, which allows so set a completely automatic mode, Program AE, Aperture and Shutter Priority, Manual. We should note an interesting peculiarity here. ISO is selected individually for each mode. While modifications in other parameters are applied to all modes. Besides, the upper dial allows selecting "scene" modes: portrait, sports, night-time. The same dial sets the video recording mode. Unfortunately, you can change the focal distance only before the recording is started.
The upper dial can also be used to set the camera to playback mode, settings mode, and the transfer mode. Exposure and aperture are selected with a small dial on the side panel. This dial selects exposure and aperture, as well as expocorrection. To switch from exposure control to aperture control, you should press the left arrow on the mini joystick. The up arrow of the mini joystick allows to control the shooting distance: 1m, 3m and infinity, which significantly reduces the interval between the shots and allows not to scare people with your autofocus assist light in case of insufficient illumination.
Manual focus is the only thing, except for the lens, which distinguishes this camera from older and more expensive models. Like film cameras, digital photography has two approaches to focusing. Focusing by the range scale using a tape-measure or a range-finder and focusing based on image sharpness evaluation. One cannot say that the former method is cheaper to implement in digital cameras. By analogy with film cameras, only expensive digital cameras are equipped with visual evaluation systems. Indeed, it's more expensive to use only both methods. There is no need in lens adjustments when evaluating image sharpness on a matrix using hardware (autofocus) as well as visual methods. The only requirement is that lens must move to a distance less than the focal distance, in this case you can accurately focus at infinity objects looking at the display. Of course you will need a magnifier to provide accurate focus, but as the cameras are all equipped with digital zoom anyway, implementation of this feature is up to software and it will not affect the production price of a sample. Focusing by the range scale implies accurate adjustments of lens in each camera to infinity focus. Each camera has to be installed on a testbed and regulated by adjusting screws or by recording the lens position to the camera firmware. The second method is cheaper, but it requires pecking motors, which only have to remember the number of impulses necessary to move the lens to the given position. Autofocus exchangeable lenses for reflex cameras use pecking motors as well as regular ones. While I have never seen an analog motor in a digital point-and-shoot camera. Skilled hands are more expensive than any mass-production device, and their use for only one adjustment procedure is economically unjustified. Though the focusing approach used in this camera requires adjustments, it seems to me that this procedure is ignored. Engineers hope that the technologies will adhere to all assigned tolerances and that absolutely identical cameras will be produced. Let's evaluate the required precision of lens installation.
Depth of field or depth of lens focus is called a distance along the optical axis in the image space, within which limits a given plane retains sharpness. Depth of field characterizes the limits of matrix movements relative to the focal plane of the lens, which do not damage image sharpness. Depth of field in the image space depends only on the aperture ratio of the lens (inversely proportional). That is the complete depth of field of the image is equal to doubled product of the f number by the diameter of the admissible circle of confusion. In our case 2*2,8*6 µm = 34 µm. That is this precision is beyond a slide gauge and so it requires a micrometer calliper.
Let's try and evaluate this limited set of distances from point of view of the depth of field provided by the lens. Let's assume that the admissible circle of confusion is 6µm, as in the previous case. We cannot expect more from this lens and matrix, though some cameras may probably produce better results. Then, if we set the focal distance of the lens to 7.2 µm and completely open the aperture F :2,8, the sharp image will be within the 0.7 – 1.5 m range. With the f number of 4 - from 0.67 to 1.96 m. If we set the distance to 3 m, then with the aperture F : 2.8 the image will be sharp from 1.5 m to infinity. Thus, in case of a wide-angle lens this set of shooting distances is enough to get a sharp image of any object, and you can estimate the distance to an object (1m, 3m or at infinity) faster than any automatics. With the maximum focal distance of 21 mm the completely opened aperture is F :4.7. In this case, when the distance is set to 1 m, we'll get a sharp image at 0.95-1.05 m. If we close the aperture to F :11, then considering the image deterioration due to diffraction, the minimum circle of confusion will be 8 µm already, the depth of field being from 0.8 to 1.24 m. If we set the distance to 3 m, the depth of field will be from 1.83 to 7.47 m. If we set the camera to infinity, the image will be sharp from 4.5 m to infinity. With the f number of 8 the image will be sharp from 8.5 m to infinity. With the f number of 5.6 – from 12 m to infinity.
Thus, in case of a wide-angle lens this set of distances is more than enough to shoot landscapes. In sunny weather and with maximum focal distance you can also leave the autofocus alone when shooting objects farther than 2 m. In macro mode or close-up portrait you will have to rely on autofocus. If you want to evaluate the depth of field for objects at a given distance on your own, you may use the program slightly adapted for this camera.
Modified initial parameters of admissible circle of confusion, focal distance, and aperture.
Added evaluation of the admissible circle of confusion by the matrix size and pixel number, or by the desirable photo size assumed that the photo is printed by a sublimation printer or on a 12 dpm photo paper. Click the question mark in the upper right corner to evaluate the admissible circle of confusion. To obtain a correct value you have to make a selection in the upper and one of the two bottom drop down menus. The upper menu sets the frame size, the next menu sets the number of pixels in a matrix, or the AgBr option which assumes an average film quality with a relatively good lens. If you set the frame size to 36x24 mm and select the AgBr option, the program will display parameters close to those on Industar type lenses. The bottom drop-down menu sets the photo size. Use this menu if your camera offers a lot of megapixels but you are not going to print large photos.
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