I was browsing YouTube and came across this:

YouTube - Sony NX5U Back Focus Issue (http://www.youtube.com/watch?v=z9XUFijX74Q&feature=related)

Is this a rare fault in fixed lens cameras?

Hi Shuf,

I posted that video. The NX5U that I had was defective. A properly functioning NX5U should not respond this way. At this point I think it is the case of a few isolated cameras. Two other videographers have contacted me about the same problem.

Sony is going to send me another NX5U for me to review after NAB.

I had no issues with the NX5U I used for a week, but it was just a week. I've heard two people now have similar lens/focus issues (half the shot is sharp, other half is blurry) with the Sony V1U...

heath

Hi Shuf,

I posted that video. The NX5U that I had was defective. A properly functioning NX5U should not respond this way. At this point I think it is the case of a few isolated cameras. Two other videographers have contacted me about the same problem.

Sony is going to send me another NX5U for me to review after NAB.

Thanks Mark for posting the video ... looked really scary if one were to be landed by a faulty camera like that ...

The problem is the lens has a servo controlled rear focusing element, making it varfocal. When you move the zoom it would go out of focus, so to compensate for this it goes to a lookup table that adjusts the rear focus element as the zoom is moved to keep it in constant focus. When units leave the factory without getting the proper calibration, this is a problem because they hide the flangeback calibration routine in the service menu where most people can't find it. This was the exact same problem we had with the EX1, including mine. The calibration routine is incredibly simple and foolproof, why it has to be hidden I don't understand. On my newest cam, the PMW350K, the flangeback calibration routine is found not only in the regular menu, but also accessible from a button underneath the lens.