[Nicolas06]

- Are sensors aging in terms of noise? How? What? How much?
- Enhancing DR in PP presupposes the DR are in the raw file in the first place.

Usually you don't put 5EV but more 1-2EV if you didn't mess up your exposure. On the opposite when you really need the dynamic range, it's exposure bracketing you need, not a sensor/camera that can push 1EV more.

[CDW]

Lab test, SNR, DxO, etc. They are all done on new cameras. But I have seen how quickly Sony sensors are aging, giving more and more noise even at very low ISO, so I really hope that Pentax will change to other sensor maker. And DR is the easiest thing to enhance in PP, not like noise.

I don't agree with either of those assumptions. I've used Pentax cameras (K01, K5, K3, 645Z) over the last five or six years, equipped with SONY sensors and have never experienced any increase in noise as the camera ages. Noise can increase or decrease depending on temperature but that is unrelated to aging.

As for enhancing DR in LR or PS, if the highlights are truly clipped in the RAW file, they can't be recovered. And as you push exposure towards clipping it's possible to see a color shift, especially in colors towards the yellow end of the spectrum. One of the reasons SONY sensors are popular with many photographers is because you can underexpose a stop or more, preserve highlights and pull up the shadows, readjust contrast and saturation, to take advantage of an apparent wider dynamic range. I shot with Canons for many years and their sensor technology has essentially not changed, with an inherent problem of visible high read noise at low ISO in the shadow areas when you underexpose 2-3 EV and try to recover as in the same manner as a SONY sensor. It's not an issue for Canons with studio shooting or situations with normal lighting but there are situations where the SONY sensors are simply superior.