buddy files; raw+jpg files; and thm files

[cthomas]

Is it important to keep buddy files; raw+jpg files; and thm files. And what are they good for? If I understand right these files can be recreated from the raw file if need. So why bother with them?  , 

[Mario]

If the JPG is produced by your camera alongside with the RAW, and you don't need it, turn it off in the camera.

The JPEG files usually have these purpose:

The camera use them for quicker previews on the backside monitor.
The camera applies the dynamic changes and optimizations you dial into your camera to the RAW and stores the result in the JPEG. This way other software can 'see' the manipulations you have done to the RAW in-camera. Since the algorithms are proprietary to the vendor and camera, these changes cannot be applied by other software, even having the RAW. Each RAW develoiper is different.

You can configure IMatch to use the JPEG as the visual proxy for the RAW files. This way you can see the RAW files in IMatch as they look in your camera.
When you modify the RAW in a proper RAW development software, the JPEG no longer reflects the RAW and if you don't need them, don't keep them.

The THM are usually just thumbnails, for quicker browsing. Older Canon cameras used the THM file to store IPTC metadata.
IMatch does not use them for anything.

[clpratt]

The THM are usually just thumbnails, for quicker browsing. Older Canon cameras used the THM file to store IPTC metadata.
IMatch does not use them for anything.

I have older Canon cameras. When they record video in AVI format they also create THM files which I believe IMatch does use to display the exif and a thumbnail.

[Mario]

IMatch still has the special THM handling. But it's much better to use a XMP file alongside the video file (XMP in sidecar files can be used for any file format). IMatch will create an XMP sidecar file when you write back metadata to video files. Then the THM is theoretically no longer needed.

ExifTool can also extract metadata from many video formats and IMatch maintains these as well in the database. ExifTool cannot necessarily also update video files so data you want to retain should go into XMP data. IMatch can use it anywhere and your data is also saved 'outside' IMatch in the XMP file.