Beginner problem w/ focus and backfocus

[Petri Teittinen]

Petri,
Send me a picture of how you installed the mount- maybe I can tell from it...

I'm fairly confident the issue, whatever it is, has nothing to do with your mount. After all, I've shot some perfectly adequate looking footage using it - and some of the footage has actually been in focus. It might've been an accident, but nevertheless

The best way to set your back focus is with a short zoom pointed at a chart at close distance(the closer the better). The distance doesn't matter for the zoom- all you need to do is get the focus sharp at the long end with the focusing ring on the lens, zoom out wide and refocus with the focusing ring on the camera-don't touch the lens's focus ring now. Now zoom back in(long end) and repeat.... do it as many times as necessary until both your zoom ends are as sharp as they can be... Remember- long end: lens focus-wide end: camera focus.(only)

OK, that's one more method to try out, cheers.

Don't worry- we'll figure this out- a lot of big brains on this forum:wink:

I've noticed that, aye. Although not too many folks have commented on issue #2, i.e. image looking extremely sharp and in-focus on the LCD, but turning up soft and out-of-focus in RDX. Surely this can't have anything to do with backfocus, as the LCD is only showing what the sensor is getting, right?