TIPS - How to Determine the Total Number of Shutter Count on Your Camera Using Photoshop
Need to find out how many photos you've taken with your camera? This information tells you how much usage the camera has actually had (especially if you intend to sell your camera).
The shutter is a precision device (usually electronic mechanical) that allows light to pass for a determined period of time for exposure of the camera sensor to light to capture an image. The shutter unit has a limited mechanical shelve-life before it has to be replaced
To check the Shutter Count, open your RAW file in Photoshop. From Photoshop File menu, select File Info...
This will open up the file information window below. Select the Advanced tab and expand Schema (http://ns.adobe.com/exif/1.0/aux])
Look for aux:ImageNumber: - this is the number of shutter count of your camera ! This number gets incremented by 1 every time to take a new photo.