Mostly, outside of Manufactuer faults, Warranty can mean they dont charge you for the service fee if you ask them to do something, like cleaning, they only charge you for parts or resourses...
Olympus once only charged me for a new front element and the front part of the casing of a lens but didnt charge me for any of the labour or time etc and they normally charge to inspect and look at the thing sometimes. Sometimes it costs $200 bucks JUST to look at the issue b4 repairs outside of warranty.
1) Olympus OM1 [Zuiko Auto-S 50mm f/1.8]
2) Pentax MZ-60 [Sigma 28-90 & 100-300]
3) Canon 7D [EF-S 15-85 & 70-200mm f/4 IS]
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