1. T

    Nifty fifty STM - focus issues, or human error?

    I have a question for users experienced with fast primes. Today, I tried to test AF with my 700D (T5i) and my two lenses: - EF-S 18-55mm 3.5-5.6 IS STM - EF 50mm 1.8 STM I noticed an issue with the 50mm. When I open up the aperture to the max, the AF jumps a bit on every other photo. But...
  2. M

    I'm worried about some "greasy marks" I found on my Canon 50mm STM Lens.

    Today while I was cleaning my Canon 50mm 1.8 STM lens, I noticed by using the DOF preview button that when it was on f22, there were some visible streaks or oily marks on the aperture blades. I don't know if this is normal, or if this is the way this lens was designed, or if I did something...