View Full Version : V1U and Backfocus


Will Boggs
April 2nd, 2008, 08:05 AM
I once owned a PD150 and didn't like that it seemed to have a backfocus problem. I could zoom into a person, focus then zoom out and the person's face would be slightly out of focus and the background was sharp. I have seen this many times on TV programs over the years, knowing that it was shot with a PD150 or other Sony cam.

I am wondering if the V1U has this problem. I need a small HDV cam and the V1U fits the bill nicely.

BTW: I sent my PD150 in for service and had them check the backfocus. It came back with the same issue. I sold it and bought a Panasonic DVX100, then a DVX100A. Haven't seen the problem since.

Is anyone else seeing this?

Lee Berger
April 2nd, 2008, 10:23 AM
Will,
I had back focus problems twice with my V1U. Here is a link to the most recent thread. BTW, Sony did fix it both times. So far no issues to date.

Lee

http://www.dvinfo.net/conf/showthread.php?t=106877
http://www.dvinfo.net/conf/showthread.php?t=108511

Seth Bloombaum
April 2nd, 2008, 10:53 AM
One thing to be aware of on the V1 is that the macro setting will slightly shift the backfocus. You only need to get caught out on this once...

Stephen Armour
April 25th, 2008, 05:33 PM
Will,
I had back focus problems twice with my V1U. Here is a link to the most recent thread. BTW, Sony did fix it both times. So far no issues to date.

Lee

http://www.dvinfo.net/conf/showthread.php?t=106877
http://www.dvinfo.net/conf/showthread.php?t=108511

We just discovered the backfocus probs of the V1 and are not happy. We had begun to suspect something was wrong in the field, but when doing greenscreen work today, we proved that it is indeed a serious prob. Unfortunately, we live and work in Brazil and a fix is very difficult.

Not very happy with Sony and with our V1 now. Anybody know of some manuals we can download and DIY? I'd be willing to try, just to salvage this V1.

Looks like we'll be looking for a new EX3 in July when they come out...or maybe a non-Sony solution...

Oh yes, and just so no one suggests it...the reset button doesn't help...

Alan Dunlop-Walters
April 26th, 2008, 04:49 PM
A lens which retains the same focus point both zoomed out and zoomed in is known as parfocal. I know my FX7E lens is NOT parfocal, and therefore doubt also whether the V1 is. It is not a fault, merely a feature of the lens. I believe that most long zooms are NOT parfocal.

Stephan Stryhanyn
April 27th, 2008, 01:38 AM
I know my FX7E lens is NOT parfocal, and therefore doubt also whether the V1 is. It is not a fault, merely a feature of the lens.Then why does the FX7E manual state (p.31, Adjusting the focus manually): "Tips for focusing manually: It is easier to focus on the subject when you use the zoom function. Move the power zoom lever towards T (telephoto) to adjust the focus, and then, towards W (wide angle) to adjust the zoom for recording"?

But I too have doubts on whether this really performs as specified.

Jon Shohet
April 27th, 2008, 09:14 AM
Just my own humble experience - as soon as I found out about the macro setting issue and turned it off, I have not experienced any focus shift when zooming in to focus and then zooming out again to recompose.

cheers.

Lee Berger
April 27th, 2008, 09:47 AM
I had this problem twice and it's been fixed twice by Sony under warranty. The last time was in the Fall of '07. Since then it's worked properly. Zoom in, get your focus and then zoom out to frame the shot. I verified this two weeks ago on a shoot. No focus problems.