I'm raising this thread to the top to let people know how things turned out. My original complaint was that the photographs of my beads (which I sell for a living) were coming out very soft.
My initial solution was to increase the ISO to 400 because that caused the aperture to be smaller. Several people advised me to just set the aperture to where I wanted it, and that's what I ended up doing. I'm now setting it at F-5.6, and all my shots are coming out sharp (except for the occasional shot that has severe hand shake).
For 12 years I have been photographing my beads in natural daylight in front of a window, and I think I am going to abandon that also. Daylight from the window (meaning ambient daylight, not direct sunlight) makes the beads look washed out, and I was also getting a huge reflection on each bead from the window. (Direct sunlight doesn't work because the shadows are too dark.)
Amazingly, the ISO capabilities of this camera are so good that I can get really excellent results from photographing under one 60-watt (equivalent) bulb. My old point-and-shoot camera couldn't make anything look good under such a weak bulb. After 12 years of using a point-and-shoot, it's pretty shocking to be able to put beads on a plate, stick them under my desk lamp, and get fabulous pictures.
In my desk lamp I use a daylight-balanced bulb (5000 kelvins). Since 5000 kelvins is "daylight", I initially set the camera to daylight" and then to "cloudy", but the photos came out way too yellow. So I looked at the camera settings, and I was surprised to find that the camera has three florescent settings: 4200K, 5000K and 6500K. Setting the camera to 5000K resulted in nearly perfect pictures. I took photos under a 60-watt-equivalent LED bulb and also under a 75-watt-equivalent florescent bulb (both 5000K), and the florescent bulb gave me the better results. I am getting a light reflection on each bead from the bulb, but it is smaller than the light reflection that I get at the window, so it's not a problem.
The color-accuracy of this camera is so good that I haven't had to make any adjustments to the colors (so far).
So anyway, that's where things stand, just in case you are curious. I am still grateful for all the good advice I got.
What a fabulous camera this is!