[font color=\'#000000\']This means that at least in theory a manufacturer could design a lens with a variable aperture which could shift during the exposure and tap the "potential" for much greater dynamic range latent in the sensor.[/font]
[font color=\'#000000\']Lin,
Can you elaborate on this! Seems to me an aperture that varies
during the exposure will simply give you one average exposure and solve nothing with regard to dynamic range. You need at least two separate exposures (I guess this is what you meant).
Two exposures with different f stops will need software similar to Helicon Focus to combine the different DoFs and I see that as problematical since parts of the two images might consist of a well exposed out-of-focus patch which has to be merged with a severely underexposed in-focus patch also deficient in detail for different reasons.
Two exposures with different shutter speeds is the usual approach (or 3 with autobracketing), but requires the subject to be static.
Those who own good RAW conversion software, such as Capture One or Adobe Camera Raw (V.2 or later) can get (roughly) a couple of stops of extra dynamic range out of a single exposure using the following procedure.
(1) Overexpose the image by one stop.
(2) Use exposure compensation during conversion to recover highlight detail.
(3) Do a second conversion but this time move EC the opposite direction, say +3 stops, to create an image with maximum detail in the shadows but completely blown out highlights. (It's probably advisable to move the NR and Luminance Smoothing controls to their maximum also.)
(4) Combine the two images with a 'digital blending' technique. Michael has a tutorial on this.[/font]