Take a larger image of the date/mintmark area. When you have that use a business card to see if it is a Large/small date. How? On your monitor.
Also look at the inside loop of the '9':
Only the Large date has that loop that year on the 'S' mint coins.
Location of the bottom of the '7' is also what I watch for. With these tricks you can search eBay auctions and if the coin is rotated, with the card you will know for sure. (They often rotate the coin on purpose to confuse you, to try to sell you not the read deal) But now you know what exactly what to look for on these.
CoopHome: How to easily spot a 1970-S small date cent, so I can know for sure if it is the real deal?