Thanks for posting those samples.
OK, as I thought from your description that’s not what I would call an issue of Depth of Field (DoF). That’s purely an issue of exposure. You’ve exposed for the foreground, to get the detail of the faces, meaning you’ve exposed for the Darks, which is a good thing, consequently this means the background, the mountain over the shoulder, is over exposured or “blown”. I’ve not heard of the phrase DoF being used in connection with Exposure. The reason your first sample is revealing the layers going back through the distance and the nice Sky, is because you’ve exposed for the Brights. This in turn gives you much of detail from the Foreground through the valley, up to the sky. This, again, I wouldn’t describe as an issue of DoF. I’ve always understood that DoF to be the manipulation of Focal Length in conjunction with, yes, the Aperture to either increase or decrease softer focus from the actual point of sharp focus. This is not the same as setting exposure for Brights or Darks.
I’ve just attempted to reduce the blown sky, but unfortunately it’s blown out. There aren’t any useful pixels to use to bring back the detail of the Sky. Others may have a go.
Now, in going forward, and in this example I try NOT shoot towards the light source, here that’s the Sun. Meaning NOT requiring to increase exposure to get the Face details and to open the Iris to expose the face detail. To do this I would either reframe, move the camera OR use a Graduted ND filter to hold back all those Brights. You’ve chosen a really difficult situation and beyond getting sharp focus this has to be uppermost in all camera operation.
If you like, I could demonstrate a simple Histogram revealing the amount of Blowout. Oh yes, I use the inbuilt Histogram that reveals the amount of blowout or “clipping” I’m getting before taking the photo.
