Painter opacity problem

[krisztiantobias]

My code is:

QPainter painter(this);
    painter.setOpacity(opacity/255.0);
    painter.setBrush(QColor(0,0,0));
    painter.save();
    painter.setPen(QPen(QBrush(QColor(0,0,0)), 5, Qt::SolidLine, Qt::FlatCap, Qt::MiterJoin));
    double meret = 60.0;
    painter.drawArc(QRectF(-meret, -meret, meret*2, meret*2),0*16,360*16);
    painter.restore();
    painter.setPen(Qt::NoPen);
    painter.drawRect(QRectF(-5, -meret, 10, meret*2));

QPainter painter(this);
    painter.setOpacity(opacity/255.0);
    painter.setBrush(QColor(0,0,0));
    painter.save();
    painter.setPen(QPen(QBrush(QColor(0,0,0)), 5, Qt::SolidLine, Qt::FlatCap, Qt::MiterJoin));
    double meret = 60.0;
    painter.drawArc(QRectF(-meret, -meret, meret*2, meret*2),0*16,360*16);
    painter.restore();
    painter.setPen(Qt::NoPen);
    painter.drawRect(QRectF(-5, -meret, 10, meret*2));

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The end result is:
74391548.jpg

But I want this:
nvtelen1j.jpg

How can I do that with drawArc and drawRect?