I got the Sony 28-70 kit lens you mentioned initially, can be picked up for very little. Not much slower than the zeiss 24-70 and little difference in performance. I use the cheap commlite adapter for my existing canon lenses and it has worked fine, no problems so far although as mentioned forget using af with any of these adapters. The I.s. Works with the commlite once you start recording, threw me at 1st but I guess it saves battery a little. I also find myself using canon fd 50 1.4 a lot with this camera for stills and video, gives a lovely creamy image on full frame Am tempted to get the Sony 50 1.8 oss for crop mode, oss is nice to have at that focal length - tried it in a shop on full frame and with zoom function at 1.3 and the image quality is great with no obvious vignette. Worth a look