Is it hard to re-name by camera time, I can't imagine how to do that.
I plan to try it in DPP. You mix all the files from the
different cam's into one folder. Then ...
1. Edit > Select All
2. View > Sort > Shooting Date/Time
3. Batch Process > New File Name
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Hi, Shadow.
Okay, Okay ...
I may have found a better/proper way to go about the renaming
in DPP. Haven't tried it yet but:
You mix all the files from the two cams into the same
folder and then ...
1. Edit > Select All
2. Tools > Start Rename tool
3. In the top 3 boxes select "Sequence Number"/"Shooting Date Time"/"Original File Name" [What my step 3 is doing is setting the NEW file naming sequence.]
4. Under Basic Settings check the box Sort by "Shooting Date/Time"
5. Under Format Settings select "Month Day Year" for the top
box and "Month Day Year Hour Minute Second" for the lower box
6. Check the box "insert underbar"
7. Hit "Execute"
I think one problem with the first way I showed you
is that it would involve processing/rendering the RAW
files [I shoot RAW] to all jpegs or tiffs or whatever
to do the re-name. I believe this new way I found
is just a file re-name involving no processing.
Plus, it shows you the before and after names of
each file and I can see that it is sorting by
date and time - it includes the date and time of the
shot in the file name as well as the original file name
AND it is re-naming the files 0001, 0002, etc.
If anyone would like to discuss this further let me
know ... or share your results if it works! 
