The meaning and difference of "subsectime","subsectimeOriginal"and"subsectimeDigitized"?
Subsectime is the fractional part of the time in seconds. It literally is the part you would put after the dot in a decimal number. This is a bit confusing as it is normally a string of two digits, so the number would be in 1/100th of a second, however, it sometimes is a number with just 1 digit. In which case the number is a 1/10th of a second (haven't seen any with three digits). So 1 and 10 both mean 0.1 second.
The Original group of time data denote the time the image was created. The Digitized group is the time at which the image was digitized. For digital cameras these two should normally be exactly the same.
The subsectime without any group could (should?) be the edit time, but in many cases I have seen, it is actually used as the Original time sub seconds...
Hope this explains things a bit :)