Here's the failed cmd with "-v" output:
TTs8X:~ tempi$ exiftool /Volumes/DQ2/Pictures/Eye-Fi/08.03.12/K20_9876.JPG -MakerNotes:LensType='a' -v
Warning: Can't convert Canon:LensType (matches more than one PrintConv)
======== /Volumes/DQ2/Pictures/Eye-Fi/08.03.12/K20_9876.JPG
Rewriting /Volumes/DQ2/Pictures/Eye-Fi/08.03.12/K20_9876.JPG...
Editing tags in: APP0 APP1 CIFF ExifIFD IFD0 JFIF MakerNotes
JPEG APP1 (34333 bytes):
Rewriting IFD0
ExifByteOrder = MM
Rewriting ExifIFD
Rewriting MakerNotePentax
Warning = Error writing MakerNotes:LensType
Rewriting ShakeReductionInfo
Rewriting AWBInfo
Rewriting CameraSettings
Rewriting AEInfo
Rewriting LensInfo
Rewriting FlashInfo
Rewriting CameraInfo
Rewriting BatteryInfo
Rewriting AFInfo
Rewriting ColorInfo
Rewriting ShotInfo
Rewriting UnknownInfo
Rewriting InteropIFD
Rewriting GPS
Rewriting IFD0
JPEG APP1 (4622 bytes):
JPEG APP13 (110 bytes):
JPEG DQT (130 bytes):
JPEG DRI (2 bytes):
JPEG SOF0:
JPEG DHT (416 bytes):
JPEG SOS
Nothing changed in /Volumes/DQ2/Pictures/Eye-Fi/08.03.12/K20_9876.JPG
Warning: Error writing MakerNotes:LensType - /Volumes/DQ2/Pictures/Eye-Fi/08.03.12/K20_9876.JPG
0 image files updated
1 image files unchanged
I had tried to edit an existing entry in the MakerNotes section.
Any idea what went wrong there? It's the first time I've tried, so I can't say that it ever worked before.
Do you need a Pentax img? I think you might have one already.
Oh - I just realize: I've tried to set a text value to a field that probably is numeric.
How do I do that, then?
The goal is to override the ID for "K or M lens" with an "unknown" value so that OSX then take the LensModel that I'm setting explicitly. As long as OSX recognizes the LensType, it ignores my added LensModel setting.
The problem is that this value is stored differently for some Pentax models. Some models (like your K20) add extra bytes to the value of this tag, and ExifTool doesn't currently write these. I'll see what I can do about adding this ability in the next release.
- Phil
Isn't the LensType value stored as two consecutive bytes? So, setting it as a 16 bit number would be sufficient for my needs, and probably for others too, if it's documented.
It is stored in various formats in different places in the images by different models.
ExifTool re-organizes the value into 2 integer numbers for each case so a single lookup table may be used. You can write the numbers directly with -n -lenstype="4 39", or by name. In the example you used, writing -lenstype=a would assume you meant "A Series Lens", for a numerical value of "2 0".
See the Pentax LensType values (https://exiftool.org/TagNames/Pentax.html#LensType) for the full list.
I have updated the code to be able to write this for all models, and I expect to release the new version (8.81) on the weekend.
- Phil