11. Photographing Techniques

11.1 Photographing without Backlight Compensation
    When taking a picture against the sun, it is common to execute the "Exp. bias" slider to the + side since a subject is taken in underexposure.
    Of course, it couldn't be better than that you can determine an optimal exposure bias amount at the time of taking a picture,
    however, sometimes a case is not like this. The shutter at the right moment might be against the sun!
    If you are taking a picture with a RAW file, give the first priority to the photo opportunity. Because this opportunity will never come again.
    In a case of the RAW file, the exposure bias can be executed after taking a picture.

    When you are using the camera which has a large-sized sensor with high S/N value and much capacity, you can "photograph without backlight compensation" without caring about a backlight condition too much.
    We recommend you to give the first priority to the photo opportunity and take many pictures. Now, you can take a picture in the way that was not available in the past.

    There are many digital single-lens reflex cameras that have a large-sized sensor and much capacity. Would you like to take a picture against the sun without caring about a backlight by setting the camera to the minimum ISO speed?
    Then why not enjoy executing the exposure bias of SILKYPIX®?

11.2 Should RAW be photographed with Underexposure?
    Some portion is true and some portion is false.
    Even in the case of RAW files, the most idealistic way is to take a picture at the maximum exposure level that image sensor linearity can be secured.
    If a picture is taken in underexposure, a noise increases and a picture becomes rough.

    However, there is a case that things do not go that way.

    (1) Contrast is high: A subject is exposured to the strong light, a metal subject etc.
      Even in the correct exposure, some portion will be gone.
      In this case, if a picture was taken in underexposure, details of the highlighted portion would not have gone by executing the exposure bias at the time of development.

    (2) Correct exposure cannot be determined
      You might miss a photo opportunity or spoil the atmosphere of the surroundings because you have difficulty in determining the exposure at the time of taking the picture.
      If a picture is taken in underexposure, an adjustment is available at the time of the development, however, if you lost a part of image you cannot adjust it.

    For these reasons, it is said that "RAW should be photographed with underexposure."
    Another reason is that by taking in underexposure, you can modify degradation of a color reproduction. Refer to 'Super-High-Techniques' (---> '12.2 Linearity and Saturation of Image Sensor').

11.3 Turning Exposure Bias Dial into ISO Sensitivity Dial
    You have to take a picture with high-sensitivity in a case of a dark subject, and a case of a high-speed subject with a long lens.
    It is difficult to take a picture with an insufficient shutter speed even though it is full aperture.
    Perhaps, in a situation like that, you increase the ISO speed.
    However, to change an ISO speed is a cumbersome task, isn't it?
    Instead, to execute the exposure bias is an easy operation among many cameras.
    Now, instead of increasing the ISO speed, adjust the exposure bias dial to the - side, to gain enough shutter speed and aperture.
    This is the technique only for photographing with a RAW file.
    In the case of photographing with a RAW file, a sensitization is available at development process, and its result is almost the same as the case of increasing ISO speed on a camera. In some scenes, a result would be much better than that.
    Refer to '10.3 Difference between ISO Sensitivity Adjustment with Camera and Exposure Bias at Development, and Application.'

    From the time you set to record in a RAW file, the exposure bias dial changes to an ISO speed dial.

11.4 Appropriate Exposure for RAW photography
    Here, define the term Appropriate Exposure as the optimal exposure which can represent a scene most beautifully.
    Note that here, user preferences such as your liking for color deviation in dark region, or for colors just before the highlighted portion goes out and so forth, are excluded.
    The appropriate exposure expose the brightest portion of a picture, where its details must not be lost, to the maximum value that linearity of image sensor can be secured.

    In other words, the appropriate exposure gives the maximum light quantity that will not cause a lost of the portion on the RAW data.
    This exposure allows you to use full of a dynamic range of an image sensor, you can obtain a clean picture with little noise.
    Refer to '12.2 Linearity and Saturation of Image Sensor' for more details.

    When taking a picture with this exposure, its value is different from the appropriate exposure that an exposure meter indicates.
    The exposure that an exposure meter indicates is determined by assuming an average reflectance of a subject. In a case of the RAW photographing, adjustment is available at the development. Therefore, the maximum exposure value that the highlighted portion will not be gone is the best.
    Although, it is very difficult to determine the exposure.
    The best way is that you adjust the exposure until the maximum exposure value after taking a picture. When you do that, use the highlight warning preview mode of a camera to check the picture. Also, adjust the maximum exposure value to the point that highlighted portion will not be gone.
    Since the highlight warning preview displays a case of recording it in a JPEG file, for some cases, it is good to give more exposure. It depends on the camera you are using.
    Please also refer to '12.2 Linearity and Saturation of Image Sensor' and '12.1 Desensitizing at Development' for more information on this super-high techniques.

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