12-29-2018 10:31 AM
The problem with fungus, and I am not sure that is what you have, is it does physical damage to the glass itself. So simply cleaning it will not fix it. That is why it must be dealt with as soon as possible. Call Canon and ask 1-800-652-2666.
12-29-2018 08:25 PM
Canon will definitely repair it. Whether the repair is a cleaning or an element replacement will depend on how bad the problem is. As Ernie says - give them a call.