yes, i know that the max marked shutter speed is 400th on the lens. but its not quite as simple as that. the HC lenses have a different shutter speed depending on the size of the aperture. i know the leica s2 was bragging about it being the only lens that does what it claims when it comes to shutter speeds at all apertures.
also, it takes less time to cover a small area with a shutter than a large area, so that equals a faster shutter speed. the difference maybe negligible, i dont know (thats why i asked).
but i got very interested when the phase leaf lenses claimed 800th sec on the full frame sensor, and a very impressive 1600th of a sec on a small p40 sensor- thats a massive difference. i doubt the phase lenses are sophisticated enough to only open partially to get these speeds (but they might be). phase people, please inform me.
the way i see it, the full frame shutter speed that covers 6x7 cm takes a certain time, but if it only has to cover a very small area of well under 4.5 x 6 cm, then it is faster.
i know this is boring tech thinking, but the difference between 400th of a sec and 800th is massive if you are shooting movement combined with ambient. if this is right, then its important.
the only way of knowing is test it i guess.
paul