Damn that Diopter
My new Canon 50mm f1.8 lens broke the other night. Well maybe it didn’t, but it definitely scared me.
One of our cats was acting particularly cute and Christa was begging me to bring out the camera to get a shot. I went and grabbed the camera, and as I lined the shot up I half pressed to shutter button to focus. Nothing happened, so I thought it must be set in manual, and proceeded to adjust the focus ring. There was a soft crack sound and then the focus ring turned normally. I stopped immediately and checked the lens properly only to see it was in fact still in AF mode. Oh dear.
After switching the lens to MF and then back to AF, I attempted to focus again, this time the AF started, but when I got the familiar focus beep the image was still completely blurred. I switched to MF and attempted to focus manually, at no point could I get the image to focus even remotely. I felt a sick feeling in my stomach as I realised the lens was probably broken and would have to go in for repairs, which given that this is South Africa would probably require time and effort, large amounts of both.
Having read on a forum somewhere that this cheap lens did sometimes have a problem with it’s MF/AF switch, I continued to play around with the lens, switching back and forth between AF and MF modes in the hopes that it would start working again. The focus ring worked regardless of where the switch was and the AF would not get a clear picture in the viewfinder. Eventually I gave up, and was about to take the lens off and find its packaging, when I decided to just try take one shot with the AF active. It was perfectly sharp! I finally clicked, that little diopter dial on the side of the viewfinder (which I never use due to 20/20 vision) had been accidentally been turned to the max. Relief combined with a bit of embarrassment, such a newbie mistake. So if you ever think the AF of your camera is gone wonky, remember to check that diopter dial before you begin to worry.
The ability to manual focus while in AF mode is still there, and I’m pretty damn sure it isn’t supposed to be like that. I can autofocus and then change with the focus ring. Am I being stupid here, or is this a sign that the lens needs to be repaired soon?
