Raw *.thm File ???

[Bruford]

Do I need to keep the *.thm files my 10D make when shooting in RAW.
If I do need them what are they?

[cmM]

they're the thumbnails used for LCD preview, I think. I don't even bother copying them from the CF card.

[thomascanty]

they're the thumbnails used for LCD preview, I think. I don't even bother copying them from the CF card.

You should. They contain a lot of the EXIF data that isn't in the CRW file...

[cmM]

You should. They contain a lot of the EXIF data that isn't in the CRW file...such as ?

[mattchase]

The THM file is mostly used as a quick preview on the camera LCD, but it does also contain some EXIF info. As far as I can tell, the only additional info the THM file has that the CRW doesn't is Custom Functions settings. So if you want to keep the Custom Function settings info, them keep your THM files. Otherwise they are safe to delete.

Here are screen caps of the same RAW file, first with the THM, then after deleting the THM.
http://www.matthewchase.com/digitaldingus/with-THM.jpg
http://www.matthewchase.com/digitaldingus/without-THM.jpg

(Re-Edit: server is back up and running)

[cmM]

aha, I see.

I learned something new today :-P

[thomascanty]

As far as I can tell, the only additional info the THM file has that the CRW doesn't is Custom Functions settings.

I knew as I posted my message that "a lot" was really the wrong choice of words, but I was on an extremely slow dial-up connection and didn't want to go back and edit that to "some". Thanks for the clarification...

[robertwgross]

To look at it one way, saving the .THM files means that you have to save twice as many files (as just with .CRW). However, the .THM files are really tiny, so space-wise, they don't hurt. If you ever study EXIF information after saving, then .THM files might become handy, but if you never study EXIF afterward, forget them.

---Bob Gross---

[Bruford]

Thanks for the info. It was helpfull.