Hi, this is my first post here. I have a brand new GFX 100S and have encountered an unusual problem. When the camera is set to Mechanical Shutter, IBIS off, and mounted on a solid tripod, the resulting images are not sharp when the shutter speed is slow, like 1/30 or so. This is clearly visible when zoomed in to 100%. When shutter speed is fast, like 1/650 or thereabouts, it's not a problem. When the camera is set to Electronic Shutter the images are perfectly sharp every time, also with IBIS turned off, at any shutter speed, even up to 1 second. I have the 250mm F4 lens and the 110mm F2 lens, and the same thing happens with both lenses. I'm doing landscapes, which involves a lot of longer distance images.
I don't mind using Electronic Shutter if that's the only thing to do, although I know rolling shutter can be a problem under certain circumstances.
So my question is: do any other GFX 100S users have the same experience, or do I have a slightly defective camera?
I have attached two partial photos of exactly the same subject, at 100%.
