Hi
What @PUTV means you can see here in the pictures: First launch I'm a newbie - #29 by PUTV
You set a fusion value lets say to 0.10mm (usually don’t go below recommended value which is calculated as optimal depending on overall scanned data afaik) . Afterwards when you mesh there is a slider with a (relative) “quality” value and underneath in ( ) you see the equivalent to this value as “grid size” in x.xx mm. This grid size value should match the value you chose for fusion. If no quality setting matches it exactly, rather go for next higher value.
In our example you choose 0.10 mm for fusing, for meshing you choose quality value which equals grid size of 0.10mm , too. If no quality value matches grid size 0.10mm , go with the one which matches 0.11mm or next higher value rather than lower (0.09 or lower) so you don’t introduce artificial points in mesh, which would make it more “noisy”.
@PUTV might correct me if I am wrong 