are these examples, in dire need of a picture retake. My skills stunk a few years ago. 1883-O MS-64 Reverse toned twin, different coin, same date and condition: 1896 MS-63:
The pics are pretty good, I think the last one is the best. The detail and color are very good, just looks like you're having a little trouble with dark areas. Looks like you're using one light source. You might want to try two light sources (at 2 and 10 o'clock). See figures 7 and 8 here: http://www.coinimaging.com/photography.html The difference between one light source and two can be substantial. Figure 9 also has a little tip on slab prep, to help with the scratches and glare. I think with just a little tweaking you could have some very good pics. Beautiful coins btw.
Raider, you are 100% correct - these were taken about 6 years a. In my later pictures, I used 2 lights, moved the camera further back and zoomed in as far as the camera could go (on macro setting). That would show the color and luster much better. Here is a picture I took very recently, not perfect by any means, but better than I would have done before: