Camera And Parts Needed

I still think you're just slightly out of focus, just enough to give it a tiny bit of blur. I have to ask again...how are you critically focusing?

Yes. When you focus, does it look sharp and clear? And when you zoom into the same spot on the image after shooting, does it look the same? These shots should not look this un-sharp at this size. When zoomed-in, they must look extremely fuzzy.

If you don't mind, please email me a full-size, un-processed shot so I can see what it looks like. Maybe the one you just posted, but without downsizing or processing?

This one finished,

I think you are right I need a little more diffusion, will work on it.

Overall your dynamic range is decent. This image has a good-looking histogram, though as you note you're still blowing-out highlights. So I see 3 things this image needs:

1) Rotate the coin a few degrees CCW, unless this coin was intended to portray the folks heading downhill. This coin, probably more than any other, has a definitive orientation...North should point straight up!
2) Fix the white balance. You're significantly "in the red"
3) Add more diffusion. This will spread the light more, brightening the darks and reducing highlights

For white balance, my process is:

Start Live View

Put reference card where coin goes. Can be white index card, "18% gray" card, or any piece of paper or object that looks "white" in mid-day sunlight

Focus on the card, then defocus high so that you can't see any details of the card surface at all

Press the white balance "eyedropper" and touch the eydropper to the center of the Live View screen

Press the eyedropper again to turn off the function

Shoot an image

Review the image in DPP. Move your cursor around and note the RGB numbers on the bottom left of the DPP window. You'll see something like 86,88,87 or similar depending on your exposure settings. You're trying to make all the numbers the same, no matter what they are.

If you see big differences (>5% between any pair of colors) for instance 95,100,105 then you can either try using the eyedropper again (YMMV), or adjust it using WB shift. To do WB shift, hit the WB shift button and a box comes up with a multi-color display. Touch your cursor on a point on the color display and it will shift your white balance in that direction. I prefer to think of the shift adjustment as "reducing" a color channel. So if you have 95,100,105, you need to reduce Blue (the colors are ordered R,G,B). So in this case blue is way too high, and green is a bit too high, so touch your cursor a bit into the lower right corner, away from blue and green and toward red. Shoot the same image of the WB reference again, and check to see if the RGB is balanced. Repeat until you see almost the same levels in R, G, and B.

How does this one look,

I did the eyedropper in DPP using a white/gray paper. You should only have to do this once?