Petite parenthèse:
Je possede un M8 sur lequel sera monté le 35mm, je n'ai pas reussi à retrouver un sujet traitant du probleme de compatibilité entre le M8 et certains summilux 35mm ASPH.
Comment savoir vraiment? L'essai en faisant une mise au point à l'infini?

“Focus shift is a displacement of the sharp plane of focus when the lens is focused wide open, but the image is made with the lens stopped down. Quite literally, the optimal plane of focus moves, depending on aperture! [The simplest and only perfect solution]

“Focus at the shooting aperture — focus and shoot at f/1.4, focus and shoot at f/2, focus at f/2.8 to shoot at f/2.8, f/4, etc (by f/2.8 spherical aberration is all but eliminated). Focusing at the shooting aperture is the only option for optimal results, but not always feasible.” Why not? When hand holding the camera, this would be the natural thing to do because you would usually move a bit getting the aperture, shutter speed, and general focus correct, and then you’d manually focus or at least check the focus one more time before shooting. Ah ha, it’s when the camera is on the tripod and all focused at a given aperture that someone might decide to change the aperture say as the light changes or to get a certain effect, and boom, there goes the original focusing. If you work the way I do, then you’ll never see focus shift. I cannot imagine “street shooters” suddenly changing there aperture at the last second either. So, why spend and additional $3,000 to add a floating element just to get rid of something that never happens?

sauf si c'est un early type qui sont hélas devenus des "collectible".