crwdns2933897:0crwdne2933897:0

How do I remove the focus ring to replace it?

I believe it is necessary to remove the front casing before the focus ring but there is any procedure to follow to remove it? Thanks

crwdns2934089:0crwdne2934089:0 crwdns2934093:0crwdne2934093:0

crwdns2934109:0crwdne2934109:0

crwdns2853045:0crwdne2853045:0 crwdns2853046:0crwdne2853046:0
crwdns2889612:0crwdne2889612:0 1
crwdns2934285:0crwdne2934285:0