Why only 1/1250s @ f2.8 on DP2 Merrill?

Started Apr 21, 2013 | Questions thread
PicOne
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Re: Why only 1/1250s @ f2.8 on DP2 Merrill?
In reply to victorgv, Apr 21, 2013

victorgv wrote:

Short answer speed of leaf shutter limitations. It serves also as aperture and because for f/2.8 it has to open more you get longer exposure . With  smaller opening you will get faster shutter speed.

Leafs of shutter can open and close only so fast.

I know this is the answer... what I'm curious about is why shutter speeds of 1/4000 to 1/8000 etc.. aren't achievable with f/8 and smaller..   Ie. why does the Tv to Av relationship stop having an impact at f/5.6 ?

Hardy Steiner wrote:

So we finally had a sunny day yesterday and I wanted to take a picture at f2.8 on my DP2 Merrill. I had the dial on M and as it was very bright I just dialed in a fast shutter speed (like one I would normally use on the SD1) ... took the picture and it turned out dark. I got suspicious and then I saw in the viewfinder that suddenly the aperture was set on f4. Ok, I thought that I must have done something wrong and after playing a bit more around I realized that even in M the DP2 increases that aperture when you dial in a very fast shutter speed ... and then I remembered that it said something about this in the instructions.

Now, this basically meant that I couldn't take the picture like I wanted. I'd like to understand the reason behind limiting the shutter speed like this? If I want to take a portrait shot on a bright day at f/2.8 I can't because it's not possible (unless I happen to have a ND filter with me which I would have to buy in the first place).

Looking at the instructions it says that from f2.8 to f3.5 you can only have a shutter speed as fast as 1/1250s, from f4 to f5 1/1600s and finally from f5.6 to f16 1/2000s.

So why can I not have 1/2000s at f2.8 where I am more likely to use it than at f5.6?

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Best regards,
Hardy
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