MtnMan Loc: ID

Oh. I thought the adapter worked like an aperture ring: i.e. caused the lens to stop down. I thought the metering would then work on whatever light is coming through the lens; i.e. the stopped down amount of light.

The downside I thought you'd have is that the image in the viewfinder might be dark. But maybe not with the EVF, which should show what the actual image will be for the manual settings selected.

What I don't get is how you would know how to set the f-stop in manual.

Peekayoh Loc: UK

In the case of the Nikon AF-S adapter, it provides a (MF) aperture ring although I hear they may not be too accurate as far as f-stops go.

Some adapter info although incomplete.

The EVF shows you the light level reaching the Sensor. I normally choose (A) mode with an MF lens and the camera will set the appropriate shutter speed for correct (according to the meter) exposure and the EVF will be the "normal" brightness. Varying the shutter speed or using the compensation dial will darken/lighten the EVF as you do so (WYSIWYG).

In all this the camera assumes the aperture to be wide open so there's no need to stop down.

Obviously the Sony Adapter for A-mount lenses gives the normal camera control of aperture as does the Metabones adapter for Canon EF lenses.

Peekayoh Loc: UK

Pedestal placing?? Anyway, the essential benefit of a Mirrorless camera is that it does away with the expensive Pentaprism and Mirror Box which makes it cheaper to manufacture and the side benefit (??) is that bodies can be smaller. How much of the saving is passed on to the Customer is another issue.
I agree that IQ is the most important measure of success but seeing as a DSLR and a Mirrorless camera can/do share the same sensor, there is no essential difference in IQ.

Peekayoh Loc: UK

Having just returned from a Spanish trip, I've only skimmed this thread so I may have missed somrething but the OP asked ... It'snot a simple Y/N answer. Normal to telephoto FLs will be little different in design or size but the wider angle lenses will have the advantage of not needing a retrofocal design and should be easier/cheaper to design/make. However things are not that simple, putting the rear of the lens closer to the Sensor widens the angle of the light hitting the edges of the Sensor which doesn't behave as well as film in accepting the light. That's why some of the wider Rangefinder lenses don't work so well with the mirrorless FF Sony cameras. I suppose that's why Sony have come up with the "Curved Sensor" although it will initially come in a smartphone. It may not see use in a normal camera although it would be ideal in something like the RX1.

A good 35mm film lens will perform well on the new high res sensors, I have several that are pretty good on the A7r.

BTW, a lens for an M4/3rds camera has to deliver twice the resolution of a 35mm lens in order to resolve the same detail, that's why they aren't cheap.

Dale40203 Loc: Louisville, KY

Thanks Peekayoh. That's the type of technical response I was looking for. In other words, more would be demanded design-wise from a wide angle lens on a mirror less camera if the size were to be kept down. I suppose that makes it advantageous to use other lenses with spacers when shooting wide angle.