Vienna roast occurs at the beginning of second crack. The Vienna stage (also called Continental) to Light French stage is where you begin to find origin character eclipsed by roast character. If you buy coffee for its distinct origin qualities, it makes sense that heavy roasting is at odds with revealing the full effect of the differences we can sense in coffee due to distinct origins. Nonetheless, some coffees are excellent at this stage. Vienna is a common roast level for espresso. By the way; Espresso is not a roast. But Northern Italian style espresso is usually roasted to 440 – 446 internal bean temperature. Southern Italian (Scura) is generally a Light French Roast or a tad darker.