Change EXIF date format

Hi i'm having trouble renamin files with <ExifTool:DateTimeOriginal>

If i put <ExifTool:DateTimeOriginal> the date format becomes YYYY_MM_DD HH_MM_SS

How can i make it to YYYYMMDD?

I need to use exif data of date taken; the date of when the image/video was taken.

Using <ExifTool:FileCreateDate> uses a date years ahead of <ExifTool:DateTimeOriginal>.

The only way i see around this is use <Img Year><Img Month><Img Day> but i'm not sure where it's pulling this data from (seems like file modified date). This then creates another problem where it works for images, but not for videos.

I simply just want <ExifTool:DateTimeOriginal> = YYYYMMDD

Ideas?

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Reply to #1:
The reason why i prefer using EXIF date taken is because date modified won't work for images that have been renamed, rotated or edited after it has been imported to the hard drive.

Thus using
<Year Modified>-<Month Modified>-<Day Modified> will eventually give me problems.

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