I have a 28 - 135 mm Ultrasonic; the mechanism for the auto focus has failed, and there is some plastic bouncing around inside.
Is it worth repairing this lens?
Second question, assuming I don't get it repaired, I would like to replace it, but can't decide between the following:
- EF-S 18-135 IS STM
- Or replacing like for like (i.e. 28-135mm ultrasonic).
And lastly will either lens work with a full-frame 5D and the non-full-frame 7D?