I do not have access to a manual camera however from my research I believe that 1/30 is the fastest shutter speed which can be seen with the eye. Frame rates on moving images at 24 seconds per frame cannot be seen as single frames and this was the frame rate used in films.
The images below are identical (copy created in Lightroom) as a starting point. The first image has been tweaked in Lightroom to show the difference between how the eye records images (in an instant) and how a your camera records an image (setting dependant). The second image is shown as taken, without alteration .
The eye can only see part of the image in focus at once, however the brain assists by building up a perception of clarity throughout the image in such situations. However not all of the image will be in focus, this is perception. Over a few split seconds the eye sends multiple images with the brain processing them into a more complete and detailed image.
The eye can also see a wider angle of view than a camera, even though I was using my widest angle lens i.e. 10mm. The aperture on the lens can also be used as a tool to select what is in focus and is used to direct the viewer. The eye will tend to ignore that parts that are not in focus. The human eye also has a lot more pixels than your camera, approximately 130 million.
It is said that a 35 mm lens will replicate most closely what the eye sees, but having spent some time researching this the scientific community now believe this sits at 22mm – 24mm. I think the jury is still out.