Omega produces high-quality Swiss timepieces known for their accuracy and quality worldwide. Changing the calibration of an Omega automatic watch is typically a task for your local Omega authorised dealer, but it is possible to adjust the watch as an end user. Adjusting the movement (the internal mechanism of the watch) requires opening the watch as well as adjusting the internal mechanisms. Great care must be taken to avoid potential damage to your watch.
Place the watch in its case holder or hold the watch tightly inside a soft cloth. This prevents the easy scratching that can occur when removing the back of an Omega watch.
Place the case opener against the back of the watch, fitting the posts of the opener to the grooves cut in the case's back. Turn the opener counterclockwise to remove the back from the watch. Carefully set the watch down, to be replaced later.
Lift the antimagnetic cover from the watch with the jewellers screwdriver. Place this small metal cover to the side, to replace later when closing the watch.
Locate the small screw on the Omega automatic movement that has small notches engraved with a + sign and a - sign. This screw allows for the time adjustment. You may need to rotate the small weight of the movement to access the screw.
Turn the screw using the jewellers screwdriver. Turning it towards the + sign will adjust the watch to be 5 seconds faster per day. Turning it towards the - sign will adjust the watch to be 5 seconds slower each day. This is the only level of adjustment that can be performed without jewellers tools.
Return the antimagnetic cover to the watch movement and then replace the case back. Using the case opener, screw the back clockwise until it is tight against the watch.
Your local jeweller will calibrate your watch for a small fee, and you will not run the risk of damaging your timepiece. Be careful when using metal tools close to your watch as it can easily become scratched.