FileModifyDate as in Exif:DateTimeOriginal feature

[BogdanH]

Hi,

I'm no expert for NTFS (which I use in Win7), but I can remember FAT... FileModifyDate value is written in FAT area and when we copy file to another media (USB stick, etc.), then this value is simply copied from source FAT to destination FAT. I assume similar happens in NTFS.
As there's always only one FileModifyDate value for each file, the difference (Explorer vs console output) only depends on how is this value interpreted. I assume (again), that console output is at the lowest (API) level. Explorer however, is trying to be "smart" and makes some DateTime calculations (taking Timezone, daylight settings, etc., into account) before showing FileModifyDate value -don't ask me what's the purpose of this.
I've tried on USB stick (where FAT is used) and there's the same behaviour as on Win7 NTFS: again, Explorer interprets date value wrong.

It could be that there is no easy solution to this problem in Windows since ExifTool is limited to using the standard C I/O routines and not the platform-specific Win32 API calls.

But Exiftool writes/shows the same (correct) values as Windows console does -so, everything is fine in this regard, IMO.

Important! Just tried out, while writting this:
In Windows, if (in Control panel) automatic Daylight setting is disabled (unchecked), then Win Explorer shows correct FileModifyDate values!
Speaking for me, the case is closed

Bogdan

[coz]

Bogdan/Paul,

I'm on travel this week and have my work laptop and therefore don't have access to ExifTool or GUI.  I will try playing with some file dates this weekend.

As far as disabling automatic Daylight savings, I tried that last week and it did not seem to work.  More specifically it did not work when I was trying to adjust a file taken during Daylight Savings Time while currently in Standard Time.  I will try it again.    As far as varying implementation of DST, I believe the last change occurred about 2-3 years ago and was nationwide in the US.  The pictures I was trying to adjust were taken this year in California while my camera was set for Eastern Time Zone (I am in Pennsylvania).

So far, what has worked is resetting my system date to the same time period (i.e. Daylight Savings Time) in which I took the pictures, make the changes, and then resetting the date.

Thanks,
Chris