JEITA CP-3451 - 40 - Tag = 41487 (A20F.H) Type = RATIONAL Count = 1 Default = none FocalPlaneResolutionUnit Indicates the unit for measuring FocalPlaneXResolution and FocalPlaneYResolution. This value is the same as the ResolutionUnit. Tag = 41488 (A210.H) Type = SHORT Count = 1 Default = 2 (inch) Note on use of tags concerning focal plane resolution These tags record the actual focal plane resolutions of the main image which is written as a file after processing instead of the pixel resolution of the image sensor in the camera. It should be noted carefully that the data from the image sensor is resampled.   These tags are used at the same time as a FocalLength tag when the angle of field of the recorded image is to be calculated precisely. SubjectLocation Indicates the location of the main subject in the scene. The value of this tag represents the pixel at the center of the main subject relative to the left edge, prior to rotation processing as per the Rotation tag. The first value indicates the X column number and second indicates the Y row number. Tag = 41492 (A214.H) Type = SHORT Count = 2 Default = none When a camera records the main subject location, it is recommended that the SubjectArea tag be used instead of this tag. ExposureIndex Indicates the exposure index selected on the camera or input device at the time the image is captured.   Tag = 41493 (A215.H) Type = RATIONAL Count = 1 Default = none SensingMethod Indicates the image sensor type on the camera or input device. The values are as follows.   Tag = 41495 (A217.H) Type = SHORT Count = 1 Default = none 1 = Not defined 2 = One-chip color area sensor 3 = Two-chip color area sensor