Originally posted by jumbleview Right, This post actually triggered me to start this thread. If something designed/made more than 25 years ago sill could be used with some positive result maybe whole idea is not entirely stupid.
Great point!
A big system design issue is whether to add cost to every lens in order to make the body more affordable. The decision is also affected by wanting to maintain backward compatibility to older lenses,
There are at least half a dozen subsystems that could be either built into the body or into each lens. Examples include:
Focus movement: one in-body mechanism to move the sensor or film versus every lens needing a motion stage. Large format cameras have in-body focus movement(the bellows). Smaller format cameras have typically used in-lens.
AF sensing: These have almost always been in-body with the exception of
the first AF lenses that could be used on MF cameras (e.g., the Pentax 1.7X AF Adapter/teleconvertor). AF motor: in-body screw drive was widely used until in-lens motors became feasible and better.
IR cut filter: These have always been in-body.
Anti-alias/optical low-pass filter: These have always been in-body, too. However, in theory, the much better solution is an AA/OLPF that is optimized for each lens. (Sharp lenses need strong filters, soft lenses need no filters. In-lens filters can also be optimized for aperture-sharpness effects and corner-softness effects.)
Shutter: in-body focal plane shutter versus in-lens leaf shutter.
Image stabilization: Pentax put this in the body. Other makers put it in their high-end lenses and forced you to buy stabilization at a high cost.