I always found the swirls silly. Cameras are so powerfull now that autofocus can't really be tricked on the contrary of what article says.
'09 BSM 128i DD '98 E36 M3 - BMWCR IS #718(sold)
'01 E46 330i - Spec E46 #718 (on-build)
BMWCCA Instructor & 2013 BMWCR IS National Champ
2014 BMWCR IS 1st Loser Champ (due to fantastic BMWCR procedures.)
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