>What a funny response! There, in a camera, are not any focus >dots, when auto-focus failed! It is about bad situations also. >See D600 User's Manual. Thank you for suggestions. >
You said you wanted a means for manual focusing like the old time cameras. You either get a split image focusing screen or you use the focus confirmation dot in the viewfinder. It most certainly is there and it will appear when you are in focus with AF lenses or manual focus lenses. And yes if you are not in focus the dot will not appear.
See page 8 of your manual and item 4 is the focus confirmation dot.
edit: If you are having a problem with auto focus in low light make sure the camera is configured so the AF-assist light comes on. See page 223 of your manual.
I think I also now understand your original post. I think your complaint is that there are a lot of features built into the body that increase the cost but are no benefit to you and that there are features that are built in that you think should be made better and perform better.