That's the first layer of sealer going on.
I talked with a professional regarding him doing my basement floor. He had several comments...
If i envisioned a mirror smooth finish, i could forget about that idea. My floor was hand troweled in the 80's. If you shine a flashlight across it you will see many rises and dips. He implied that he could not grind if flat, and could not achieve what they have in say Home Depot, or a fancy trendy restaurant.
I think he could do better than what i did on the garage, but am not sure the cost difference would be worth it.
I need advice on the final finish too (if i do a sealer), as the choice for the garage floor may not have been the best, every dusty foot print shows up, and does not sweep away, you have mop it. The sealer could still be drying as it's been in the 50's in the garage, or it could just be the gloss finish, and maybe in the basement i need one not so wet glossy looking.
The various shines you seen in the picture above are representative of the finished look, where the concrete was dense and sanded smooth it's glossy, where it is more porous with aggregate exposed it is duller.