Okay, got it, should have recognized that.

Check out this query that has same output.

SELECT L.*, R.* FROM Tbl_Images AS L INNER JOIN (SELECT *, ID-1 AS RID FROM Tbl_Images) AS R ON L.ID=R.RID WHERE L.ID Mod 2=1;

Is this a class exercise? Was that advice provided by instructor? Why would you change JOIN clause to change sort order? Any field in query can be used to sort on. Why not sort or filter on form?

I can't see 'green parts' in query.

If you want to have 2 options on form to change sort order, probably need a Toggle button or Radio buttons in an option group or a Combobox, not a single Command button. Which one appeals to you?