https://en.wikipedia.org/wiki/Aperture
I am using this one because it covers a lot different uses of aperture.
In photography, we use f-stop for aperture, it is a ratio of how far the diaphragm is open as compared to the focal length. According to most places, including the one I linked to, minimum aperture does not use focal length for its calculation, so I am uncertain as to whether or not any given focal reducer will change the minimum aperture.
While it may seem counterintuitive, aperture is not affected by crop factor. The lens will always present the same circle size regardless of the sensor size. And the same ratios.
If a focal reducer makes the lens circle size smaller, it will have some effect, most reducers actually give you a wider field of view, in your case, the new 35mm vs the old 50 mm, but, …, if the sensor size was already smaller than the circle the lens presented before, the new lens circle size will not matter.
Uh, depth of field goes with f-stop, so that will be affected.
Honza reacted to jerryy in Focal lenght with Viltrox ef-fx2 adapter