The BS5 has the same dog of a problem as the BV's with the anti-reflex coating. Although it is on the reverse side, I think it sets up plenty of internal reflections which make it look smeary etc...
The method I use is to spray a clean dry kitchen papaer towel with the light blue iso-propyl alcohol based window cleaner. Wipe and saturate (but not to drip) the screen. Before it has anywhere near enought time to dry, re-wipe very quickly with one or two dry clean kitchen paper towels. This through practice gives a perfect look to the screen cover.
Same applies to a BV screen - but obviously has to be done in sections.
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