Optics
Forty millimetres, twenty-two long
How the pancake went through seven prototypes before it was allowed to be thin.
When we started on the H1, the brief for the standard lens was one sentence: the camera with this lens on must fit into a coat pocket. In practice that meant a lens shorter than 25 mm from the mount, with a full-frame image circle and no compromise on the edges at f/4.
Seven prototypes
It took 26 months and seven optical prototypes. The first, in 2022, was a fast f/2 design. It was sharp, and it was 34 mm long. Prototype four had seven elements and reached 27 mm. The final design has six elements in five groups, one of them aspherical, and the front element is just 31 mm across.
The decision that made the length possible was dropping the aperture ring. A ring with click stops, and the mechanism behind it, takes about 6 mm of barrel. On the 40 mm, aperture lives on the front command dial instead. It was the most argued-about choice in the whole project, and the reason the 28 mm and 75 mm both have a ring.
Focus at the front
The focus ring is the knurled band at the very front. A voice coil motor moves the whole optical unit, which keeps the design simple and the lens quiet. In manual focus the ring is electronically coupled, and you can choose between linear and speed-sensitive response in the menu.
A thin lens is mostly a list of things you agree not to do.
What we gave up
The 40 mm does not have a mount gasket, so the H1 with this lens is splash resistant rather than sealed. Close focus is 35 cm, a little further than we wanted. We think both were worth the 22 mm. The full specification is on the HV 40 mm page.