Robert, If f/1.1 needed, then the faster lens comes in handy. If the whole face and not just one eye brow needs to be in focus then one needs to stop down. In that event if the back ground looks then a Sonnar comes in handy.
Hope that clears it up.
Vivek, I'm not being argumentative (much!). I remember the good old days, when Kodachrome was ASA 10 and SLR viewfinders were very dim — hence the need for very wide aperture lenses.
I don't disagree with the eyebrow in focus theory, though I thought the point of focus should be on the bridge of the nose, so that the eyes, the portal to the soul, were just so slightly defocussed — important in female portraiture, to retain the eternal mystery that is woman.
And, were I to win the Euromillions, I might well go for a Thambar to replicate this, even if I don't really do portraiture. Meanwhile, I fear a GAS attack to be imminent; I see I can get this lens off ebay for around £280-290, at which price it is really a 'steal'.
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