When laying down cement backer board for a slate tile installation, I laid the board a bit too far from the wall, so I pushed it until it was flush with the wall. I think by doing this I must have shifted some of the thinset underneath, because I noticed that the board has a slight dip in it, of maybe 1/16-1/8. Is this going to be a problem, or will it be taken care of when I put thinset over it to lay the tile. This is obviously my first time laying tile.On a side note, when laying slate, is it best to use thinset or medium set, I've heard conflicting opinions.
If you use medium set, any differences in the scale you described can be corrected fairly nicely.
medium set is more forgiving.