[lm-announce] IMPORTANT - use of coarse and fine focus

[Sam Swift]

Dear All,

We've been having some serious problems with the focus wheels locking  
up on some of the microscopes as well as fairly rapid focus drift,  
which is often misreported as a problem with  stage drift.   The main  
reason for this is that the fine focus is being used too much in  
favour of the coarse focus.  I apologise if this sounds patronising,  
but please remember to focus your sample by bringing the objective  
lens to the sample (the point at which the top lens presses the oil  
onto your slide) using the coarse focus wheel and only using the fine  
focus wheel to focus the last few micrometres.  Please do not use the  
fine focus wheel to move the objectives long distances; this will,  
ultimately, break the focussing mechanism.  If you are struggling to  
focus your sample - which can be tricky for transparent and sparse  
samples - there are a few tricks to make things easier, so please do  
ask for help.  If you experience problems with the mechanics of the  
microscope just ask and we will help you reset the focus wheel  
positions.

Many thanks,
Sam