Chronographs are watches that measure time in different ways. Besides normal timekeeping they are used for one or more specific time measurements. For this, the dial has several sub dials with a scale, from which the measurements can be read.
A central second hand can be started and stopped, without interfering with the continuous time.
The design of the dial of chronographs depends on the number of subsidiary dials. This can be two, three or even four. One of them is likely to be situated on the "9" of the dial, and shows the continuous seconds.
When the chronograph is activated by pushing the top button, the central second’s hand starts moving. After one complete cycle is completed and the hand returns to "12", the minute-indicator, located at the "3", will jump one position. This simple type of chronograph can measure a period of 30 or 45 minutes.
More complicated chrono's have a subregister for total hours, often located at 6 o'clock on the dial. This enables to take measurements up to 12 hours. Even fairly simple chronographs have very complicated movements. There are chronographs that have, beside minute and hour registers, displays for day and date, and moon phase indication.
Chronographs are expensive, and certainly more expensive than a normal or automatic watch, due to the complexity and craftsmanship necessary for manufacturing. That is why maintenance and repair is also quite costly. The price of a Chronograph watch goes up according to availability and complexity. Of course, brand name has a great influence on the value.
