ac160/130 focus issues

[Josh Bass]

I keep hearing about these various focus issues with the 160/130. The autofocus stuff I'm not really worried about; hardly use it, if at all.

I am concerned about something I read somewhere else, that the the LENS ISN'T PARFOCAL????? Isn't this unusual for a dedicated video camera lens? I thought they were designed to hold focus throughout the zoom range?

This person mentioned that if you zoom all the way in, focus, then zoom quickly back out, it'll go soft again. Is this a regular thing with this camera? Was that possibly an isolated incident? I read about how macro focus kicks in automatically at certain distances and wonder if someone got confused.

I know the 160a is coming out soon with the new focus functions. . .how hard is it with the 160 to focus manually, in general? No different from any other cam (say, EX1) or are folks finding it especially tough?

[Vaughan Wood]

I find the AC130/160 to be the best camera I've owned to focus with, simply because it has a better quality viewfinder than the EX 1, and we do a lot of event and hand held stuff.

It's true that if fully zoomed in and focussed, if you fast zoom out it will momentarily go out of focus, but under normal operation (slower zooming) it is fine. According to what I read somewhere that was one of the trade offs of having such a long lens (x22).

The auto focus, if you need to use it, does a good job 90% of the time, but can get confused in darker scenes when there is no movement, which again mimics other cameras.

Let's face it, HD focussing IS very critical, but I have less problems with soft images from two AC130's doing weddings and events than I had with two EX 1's for 5 years, with several different cameramen..

Cheers,

Vaughan

[Josh Bass]

I'm surprised you say it's easier to use than the EX1 in that regard, always thought the EX1 very easy to focus with 'cause of the blue peaking. Maybe that was my mistake for assuming whatever was blue was actually sharp, though?

If you think the viewfinder (do you mean flipout or eyepiece, or both?) is better than the EX1, then it should be no problem.

Now, when you say it "momentarily goes out of focus", do you mean, even on a quick zoom out from full telephoto, that it will go briefly out of focus and then "find itself" after a moment? I don't really see a problem with that, as one doesn't typically do quick zoom outs as part of their recording (I guess that particular move has is applications though).

[Bruce Rawlings]

I have the 250 with the same lens and focussing system and have had no problems moving from an EX1. The zoom only has a very slight aberration has it pulls out if done very quickly. The lens is so long that under normal circumstances you would only use part of it anyway. Focussing is easy with the red function - I do not use auto when recording but it seems to work very quickly in turbo mode when zoomed in looking for initial focus.The quality of this range of Panasonic cameras is superb. I only went for the 250 as it has a five year warranty and the cost of an extra 64GB P2 card is cheaper than buying extended warranties on competitor's products.

[Josh Bass]

Alright gents. Thanks.

[Chris Harding]

Hi Josh

As Vaughan says if you zoom out slowly the lens does hold focus (assuming you are talking manual?) However a zoom out from 22X for me usually ends up soft..but it's hardly used... the one nice feature for run 'n gun work is that you have manual features that still work in auto...so even on autofocus you can trim the focus if the image is soft...For me AF works brilliantly in good light but is very dismal doing a Church wedding..my main cam is always in manual and my second cam doing cutaways often needs a focus adjustment when the light is low.

I run my 2nd cam on my shoulder on a rig and my biggest asset is using the LCD to focus NOT the EVF as it's near my ear!! I have a 3X loupe on the LCD so I get a HUGE screen to work on (us old guys need some help without 20/20 vision) I find the EVF IS very high res but it's so tiny I struggle with focus so although the LCD is not as sharp as the EVF it's still WAY better than other cameras and then magnify it 3 times and it's awesome...the idea came from using a Sony EX-3 and I loved the LCD inside the EVF!!!
(My old HMC80's had the same thing) Once you have that you really don't want to use anything else!!!

If you do use the EVF then make it black and white and turn on focus assist..with the LCD you can stay in colour!!!

Chris

[Eric Olson]

Originally Posted by Chris Harding

As Vaughan says if you zoom out slowly the lens does hold focus (assuming you are talking manual?) However a zoom out from 22X for me usually ends up soft..but it's hardly used...

So is this a confirmation that the lens is not parfocal, that is, when in manual mode it does not stay in focus as the zoom is changed?

Does zoom speed really make a difference in whether the lens holds focus while in manual mode? Perhaps in manual mode the firmware is still trying to adjust the lens during zooms to compensate the varifocal optics and can't keep up if the zoom is too fast. If the firmware were actually tuned to a different lens than the one on the camera, this would also explain the unusual focusing characteristics of the camera.