Hi,

I just noticed that my ex1r changed focus when zoom in and out.

For example when i set the camera to focus object at z30 and then i zoom in at z50, the object now is out of focus.

I noticed this issue when i used it with letus ultimate when i zoomed all the way to the ground glass and then zoomed out a bit, the ground glass was not in the focus anymore.

Full manual focus was on.

Is this normal?

Is it relate to back focus?

Thank you

Yes do the back focus, it is an automatic procedure.

Here is a thread about how to do it on an EX1R.

http://www.dvinfo.net/forum/sony-xdcam-ex-cinealta/477912-back-focus-ex1r.html#post1524295

Thank you

I did the back focus setting but it's still the same.

However i think i set it not properly.

I will do it again.

I tend to do back focus using a patterned wall covering or textured wall (brickwork?) rather than using a siemens chart. I also use place the camera at least 3m (9ft), more often closer to 4m, from the target wall. I've watched the camera focussing on the siemens star chart and I don't think it always nails it all that accurately.

Alister thank you for the technic.

I concur with Alister, charts haven't always worked for me either when using the automated backfocus operation.

These cameras sometimes lose backfocus at the worst time, so make sure you know the backfocus procedure.