.THM files. Any reason for them after being pulled from the camera?

[Gordon Simpson]

My guess is the THM files are used in the camera as thumbnails. But is there any reason to keep them at all after pulling them from the memory card? I suspect not but don't want to delete them till someone in the know can confirm my suspicions.

 

[DiverDown]

It seems they hold the bulk of EXIF data, so if you convert the files to another format (tiff, psd, whatever), then you don't need the .thm.

I copied just the raw files (not the thm) and Adobe only recorded some basic exif info. I did the exact same thing, only the second time I copied both the raw and.thm files to the working dir, and all my exif data was there.

Why? I don't know.

 

[Rick Pali]

My guess is the THM files are used in the camera as thumbnails. But
is there any reason to keep them at all after pulling them from the
memory card?

Some software stores applied IPTC data in the THM files if you add that information to those fields. I use iMatch and it does this...and I thank goodness I kept those files.

 

[Wayne Larmon]

My guess is the THM files are used in the camera as thumbnails. But
is there any reason to keep them at all after pulling them from the
memory card? I suspect not but don't want to delete them till
someone in the know can confirm my suspicions.

Now if Canon is going to make up their own image format from scratch (.CRW RAW format), then why did they split it into two files? It isn't like they need to answer to anybody if they found that they needed to extend the .CRW format to hold more kinds of data.

I agree with the other posters that .THM files contain EXIF (and other) data that isn't in the .CRW file, so it is best to keep the .THM files.

Wayne Larmon

 

[Rick Pali]

I agree with the other posters that .THM files contain EXIF (and
other) data that isn't in the .CRW file, so it is best to keep the
.THM files.

They tend to be less than 1% the size of the CRW so I figure they're worth keeping on the chance I'd regret it later...and that's already worked out to my advantage.