Hi, talking about receiving signals from 13°East, I found out that aligning the skew of my dish (sometimes it's better to do it, especially between cold and warm seasons) I had to turn the LNB clockwise less than a millimeter and I had a change, a good one ! You can see "before" and "after", first H and then V. I got a bit higher gain, a better C/N. That's why it's important to re-align the dish every now and again !
That's my values from Rome.
H scan, before and after skew alignment.
V scan, before and after skew alignment.