ewavr asks:
@all
Which EXIF tags would you like to see?
Well I think we should be as standards compliant as possible, on the grounds that the less we deviate from standards the more likely 3rd party software will work with DNGs produced by CHDK. The main relevant standards are TIFF 6.0, TIFF/EP (TIFF/Electronic Photography) and DNG. Adobe's DNG standard states that it is possible (but not mandatory) for DNG files to be TIFF/EP compliant. Being TIFF/EP compliant means including the mandatory TIFF/EP tags. These are:
0xfe, 0x100, 0x101, 0x102, 0x103, 0x106, 0x10f, 0x110, 0x111, 0x112, 0x116, 0x117, 0x11a, 0x11b, 0x11c, 0x128, 0x131, 0x132, 0x8298, 0x9003 and 0x9216.
ewavr's code contains most of these already, the missing ones are:
0x10e, 0x11a, 0x128, 0x131, 0x132, 0x8298, 0x9003, 0x9216
These are:
0x10e: ImageDescription, T_ASCII, tag is mandatory but may be set to null
0x11a: XResolution, T_RATIONAL, length:1, this encodes the number of pixels per resolution unit in X direction
0x11b: YResolution, T_RATIONAL, length:1, this encodes the number of pixels per resolution unit in Y direction
0x128: ResolutionUnit, T_SHORT, length:1, the resolution unit for 0x11a and 0x11b. Values can be 1:no unit, 2:inch or 3:centimeter
0x131: Software, T_ASCII, encodes the name and version of the software within the camera. Tag is mandatory, but Null value is allowed
0x132: DateTime, T_ASCII, length:20, date and time original was last modified
0x8298:Copyright, T_ASCII, Tag is mandatory, but Null value is allowed
0x9003: DateTimeOriginal, T_ASCII, length:20, date and time image was photographed
0x9216: TIFF/EPStandardID, T_BYTE, length:4, should be set too 0x00000001 (for little-endian) this signifies version 1.0.0.0
I hope this is useful. Adding these should be straightforward.
Martin