I did it again!

Two days ago I didn't know what to do (well, I had to study, obviously) so I took the train. Direction: Verona. That beautiful city, location of the world-wide famous love story between Romeo and Juliet. Verona is a medieval city, full of towers, old palaces, castles, and monuments. All this is sorrounded by wonderful hills and one of the longest rivers in Italy, the Adige. The weather was good, the sun shined and the sky was totally blue, without any clouds.
I took about 240 shots, but not all are good: some aren't sharp, some overexposed, some underexposed, some pictures are not so well composed and other simply are not interesting. In order to have an improved flexibility in what concern the post-production operations, I shoot always in RAW mode. In this way, I had the possibility to make all the important regulations (like white balancing, sharpness, contrast, saturation and other things) on my computer with its processor that is more powerful and accurate that that of the camera.
The major problem was that of the exposure: whene photographing with the sun behind me, there wasn't any problem. I just overexposed of 1/3 using the evaluative metering mode and the results were pretty good. On the other side, when the sun was in front of me, the photos were all dark. This is fundamentally due to the fact that the metering system of the camera takes the sky as a strong light source so, in order to obtain the correct exposure, it underexpose automatically of one or two stops. But that "correct exposure" is that of the sky! In that way, the subjects are all dark. To solve this problem, one usually overexpose of one or more stops, in order to have the right light balance.
However, in extreme conditions, even this technique doesn't work very well. Here is an example.
In this photo the metering mode was evaluative and the exposure compensation was of +1/3.
Exif: program Av, Tv 1/125, f/8, ISO 200.

Note that the sky is completely washed out, and this is impossible to correct in post production. So, when I saw this result I took another photo measuring the exposition on the sky, blocked it, and re-composed the frame overexposing by +2/3. The result is the following.

Exif: program Av, Tv 1/500, f/8, ISO 200.

Here, you note immediately that the sky is well exposed, but you cannot say the same for the castle: it is very dark. But, in contrast to the previous example, here you can correct the photograph in post-production, because you can extract some detail from the dark parts. But, you know, I prefer to have a right exposed photo, in order to minimize the post production operations. So I proceeded in this way: I measured the exposure on the sun, blocked it, re-composed the frame overexposing by two stops. The result is this.

Exif: program Av, Tv 1/250, f/8, ISO 200.

Here you see that the sky is only a little bit washed out but you can correct it, and the castle is right-exposed.
Clearly, it doesn't exist an universal method to obtain the right exposure. I want to underline the fact that here you can achieve the same result by modifing both aperture and shutter speed. I mantained an aperture value of 8 and varied the Tv. But you can do the inverse. What matters here is the precise combination of both values and the metering mode.

Anyway, in this page you can find the best photos (well, you'll find that photos that I consider the best!) of Verona, so take a look.