A
A factor that I believe is very important is bed temperature. Temperature will change the shape of the bed and it should be leveled either manually or automatically at the temperature you will be printing at. This is why it is important the the ABL function works. It maps the shape of the bed surface using 16 different points instead of just 4 as we do when we manually level the bed.
Unfortunately I do not believe the ABL works right in the Ender 3 S1 Pro. It seems to produce somewhat random results. I noticed that it will only uses .05 mm increments when we adjust Z and I suspect it is using the same accuracy when we use ABL. That is almost 2/1000 of an inch, which to me seems to be too large of an increment. 0.05mm is 1/4 of the standard layer height of 0.20, that seems like way too much.
BLTouch, which is similar to what Creality is using in the Ender 3 S1 Pro, advertises an accuracy of 0.01mm. That is five times more accurate than what the Ender firmware allows or about 1/20 of the layer height. That sounds more like it.
I believe the correct procedure to level the bed is to first manually level it and if you do it properly you will get it more accurately than 0.05mm, then use ABL. I am guessing that you are now loosing some accuracy if it is 0.05mm increments. It becomes a bit of a trade of as it is now over 16 points instead of only 4.
I would imagine that the 0.05 mm is a software or firmware setting and it is simply just set wrong!
