Penal Code §285 indicates that a conviction for incest includes incarceration in the state prison.
That means incest is a felony offense, and it carries a minimum incarceration period of sixteen months in prison if probation is not granted.
However, you could get sentenced to up to three years in prison, and the court can order a fine of up to $10,000.
The court can also opt to put you on probation instead of sending you to prison.