focus_on _ infinity, how about doing what Matt King asked you to? Might get us somewhere unless you are satisfied that we have solved the problem to your satisfaction. In which that seems to be the end of the matter for you and we can look towards other problems that arise on Photrio
If it is simply an agitation problem in your view then all you can do is keep altering your pattern of agitation until the problem disappears
Let us know when agitation solves the problem and what the correct agitation regime is
pentaxuser