How to find number of shutter actuations on D600??

I sent my D600 in to Nikon for repair.  When I sent it off, I had taken 890 pictures.  When the camera was returned, it appears there have been 6,369 actuations.  In other words, the first picture I took was DSC7259.

The camera is set to increment numbers, not restart with a new memory card.  I did not send a card in with the camera nor was one returned with it.

This just strikes me as excessive, if it were just used for testing purposes.

Is there any other way I can check the number of shutter actuations?  I have a MAC and cannot use Opanda or Irfanview.

Any ideas or suggestions?

Many thanks.

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Annie P.

http://www.pjphelan.smugmug.com/