HASSELBLAD Shutters: Leaf and Electronic

[Michael Erlewine]

On the Hasselblad X2d, which shutter method, ‘Leaf’ shutter or ‘Electronic’ shutter is best and why? And best for what kind of work?

The Leaf shutter exposes the entire frame at once from the inside or center outward, while the Electronic shutter exposes the frame, line by line, from top to bottom. Thus, the Electronic shutter is subject to what is called ‘rolling shutter’, while the Leaf shutter is not.

Other than the above, either shutter exposes the sensor to light. I would imagine that the Leaf shutter is subject to any mechanical artifacts of motion that exist, while the Electronic shutter has no moving parts, only the reading of the sensor, line by line, from top to bottom.

I took a photo of a very detailed still life and could not discover any real difference between either shutter method. Of course, if there were movement in the scene, the Leaf shutter would capture that with less artifacts.

The Leaf shutter makes more noise and also produces vibrations I would imagine, which favors the Electronic shutter, IMO.

I am still new to the Hasselblad X2D and would appreciate any thoughts on these two shutter methods, their pros and cons. Which do you use and why? Do the clicks from using the Leaf shutter wear out the lens?

[Akira]

The electronic shutter used to cause more noise, but the current sensors seem to have addressed the issue.  Fuji GW680 and Hasselblad 500CM were the only cameras with leaf shutters I have ever used.  I felt that the Fuji GW680 caused much less shutter shock than the 35mm film SLR cameras.  Unlike the focal plane shutters, the direction of the movements of the leaves of a leaf shutter would cancel each other.

I only briefly tried X1D and X1D II at camera shops.  The leaf shutters in the lenses sounded higher than those for the film cameras, probably because the Hasselblad leaf shutters allow faster shutter speeds up to 1/4000.

Two of the disadvantages of the leaf shutter I could think of would be the cost and the limitation of the lens design.  Each lens have to have the shutter, which  raises the cost of the interchangeable lenses.  And the diameter of the shutter limits the speed of the lens.  The fastest lens for the Hasselblad X series is f1.9, but its fastest speed is 1/2000, which would be fast enough considering the general use of the MF digital camera.

[Michael Erlewine]

And so, if I understand correctly, doing handheld with still life, the Leaf shutter is best because the shutter, instead of reading lines from the top down, the Leaf shutter is just opening up, so even with movement you get no rolling shutter and get some exposure from inside out. Right?

I have done well handheld with the electronic shutter except if the camera in tilted or at an angle or perhaps does not finish reading the sensor linerally.

[Akira]

As you mentioned in the initial post, the electronic shutter would work well enough, so long as the subject stands still.

The problem of the rolling  shutter is that the data read out speed of the sensor is much slower than the shutter speed suggests.  The electronic shutter allows very fast shutter speeds like 1/16000 or 1/32000 msec. simply because it can control the slit of the focal plane shutter much more precisely than the mechanical shutter.  But the actual line-by-line data read out speed is very slow (1/15 msec. or even slower, I guess), and thus the time duration "between the start and the end of the exposure" will depend on the read-out-speed and remains the same regardless of the shutter speed faster than the actual read-out time.

When the mechanical leaf shutter is used, the exposure time will depend on the duration of the opening of the leaves.  The data will still be read out line by line, but will not be affected by the rolling shutter effect, because the data will continue to be read out even after the leaf shutter is closed.

[Ilkka Nissilä]

Focal plane shutters cause more vibration (in the direction of travel of the curtains) than leaf shutters (where the blades move out-to-in and back in a a circular pattern). I wouldn't worry about it too much. Electronic shutter on the X2D is needed for lenses which don't have a shutter in the lens. Given the slow read speed of the sensor, I would in practice always use the leaf shutter in that camera when using lenses that have those.