Hi Chris, Im not familiar with the S5800 but have the S9600. Here is what I would do, take a couple of test shots:
1. Use manual setting on camera, (I use this all the time).
2. Pre-set your aperture to achieve the desired DOF, (depth of field).
3. Take a series of shots of the same subject bracketing, varying the shutter speed.
After a while you will gain confidence in manual mode, much better to control things yourself than let the camera do it for you.