AC130: Video footage of the Auto Focus in action

Lance,
What we have heard from Panasonic is that it is the lens design, it is the pixel count, it operates differently. We should use it differently etc. But there has been no feedback regarding the inconsistent and randomness of the auto focus.

But yes it "is what it is" and I haven't purchased what what I thought I had- a camera with a reliable auto focus. ( and I waited for the 160A because of the bad feedback on the 160) That doesn't mean to say I, or any other consumer should just roll over and accept that. It has been a bit ad nauseam I agree, but I believe that such en masse feedback was at least a contributing factor in the creation of the 160A.

Having said that I think it is a great camera apart from that issue and I will work with it. But not without a little bitterness, and the feeling that it is all our fault somehow for not accepting it as it is.. Consumers ultimately have a choice in this democratic world, and I have shelved a further purchase based solely on this one issue. I guess that is democracy in action.
This forum is a great place to discuss a wide range of topics and in this case, issues. We all have our points of view and codes we live by and I am fine for you to accept it is what it is, but please don't ask me to. Nothing personal at all meant there, I just have my own point of view.
Rod
 
Rod...

I want to keep going until I see/do not see the inconsistent behavior you and others have reported.

In my anchor/church testing (which involved switching from one scene to another travelling along varying arcs) I was able on ONE occasion to convince myself that the arc you took impacted the lock in time (possibly going through an area of high contract near the remote scene versus not going through ...) but the next day when I repeated the same test I got consistent fast lock-in.

However, in my straight line test (near subject/far object) where the subject left the scene and then came back, I got results as expected.

I also got consistent results in my straight arc tree/gazebo AF and Push Auto tests that I ran, resulting in discovery that it is best not to hit Push Auto when in AF - here, I concluded, perhaps falsely, that AF took over after a Push Auto and caused the "double bounce" that I observed. As a result of this, I see Push Auto being mostly useful at set up time.

Lastly (will he ever finish?), I found that AF seemed to keep things in focus during a hockey game where I did quick zooms when goals were being scored - you have to be fast or you miss the event and you then have to come in or you are not able to follow the puck.

The pro broadcasters have it easy, e.g. travelling cameras, plus one camera at each goal.

When you are a one trick pony it is much more difficult.

Bottom line, I have never seen the focus lock-up so I need to keep testing.

I specifically want to figure out whether the 'hunting' we see actually results in changes to focus or should we perhaps re-categorize 'hunting' as 'scanning'.

I really don't care if the camera is scanning and never finds any reason to make changes in focus. For me, hunting could mean that it is continuously adjusting the focus, quite a different scenario.

I agree with LanceOregon that Panasonic has participated in these tests by providing valuable advice here and there. (my experience).

The AC90 seems to have new OIS technology that we will not find in the AG-AC160s.

The chips, as I recall reading, are 1/4, not 1/3, so it's likely they are quite different from what is in the 160s/130s.

It would not be reasonable to expect Panasonic to recall prior cameras to do MRO on them as is the usual with military helicopters. e.g. I would love to have the LCD moved from where it is to the handle (not going to happen) .

And, is it not true that there is no ND switch on the AC90 so I am not about to move away from my 160.

My objective is to get to where I have learned how to make good use of my 160A. Starting last February, I only have 62 hours on the camera. Video is not my day job.
 
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Rod Pike said:
I would love Panasonic to at least speak to us on this- they must watch this forum. But yes, I surrender and will make the best of this camera as it does work for me and I love (nearly) every aspect of it. But sports, horses, run,n,gun, dance etc, there are more suitable cameras out there with auto focus systems that are reliable and consistent..
Click to expand...

Rod,

I have responded to this thread and more than once have I responded to the way this camera works. I have pointed to a helpful video that shows how to work with this camera and its new lens arrangement. I have discussed why it is not like the 10X or 12X lenses, and why with a higher resolution chip set the camera needs to have its focus limited by using the area focus tool. The camera is not going to be as fast as a shorter lighter lens paired with fewer pixels. While I hear that everyone wants it to work a different way than it does, that unfortunately is not going to change the way that it does work. There is not a flaw in this camera, it is a great little camera and really unsurpassed in it feature set at its price range.

And as far as this sounding like Apple in their explanation of the purple haze on the the camera portion of the iPhone 5, well they are correct, the design of that set of camera elements will cause it to work that way in certain circumstances, and you have to change your position. I have a couple of point and shoot Lumix cameras that do the same thing. You need to figure out how the camera works and then work with the camera to get the video you want.

Best regards,

Jan
 
Hi Jan,
thankyou for your feedback, appreciated. Firstly, regarding Apple I did not make that observation and have to confess I had no idea what the author was referring to.

I have watched and read everything that has been published by you and Panasonic and it all is valuable and enlightening stuff to be sure. (it's why I actually switched from Sony to Panasonic) I am happy with the slower focus and understand your excellent explanation.

My point has always been not why it works the way it does, but why is it inconsistent on the same subject on a series of cycles?- occasional complete focus lock-ups. I can't change my position on this because that is what happens- nothing to do with me. However, the more I think about it I wonder whether my camera may be faulty? (these things happen to the best of gear) This is a brand new 160A and is fabulous in all other respects. I will have a word with my local Panasonic service centre.
Rod
 
Rod Pike said:
Hi Jan,
thankyou for your feedback, appreciated. Firstly, regarding Apple I did not make that observation and have to confess I had no idea what the author was referring to.
Click to expand...

I did and that is why I answered that one.

Rod Pike said:
My point has always been not why it works the way it does, but why is it inconsistent on the same subject on a series of cycles?- occasional complete focus lock-ups. I can't change my position on this because that is what happens- nothing to do with me. However, the more I think about it I wonder whether my camera may be faulty? (these things happen to the best of gear) This is a brand new 160A and is fabulous in all other respects. I will have a word with my local Panasonic service centre.
Rod
Click to expand...

this would be a great idea Rod and show them a couple of examples. See if you can make an appointment and physically show them its misbehavior. It may well be.

Best of luck,

Jan
 
Thanks Jan,
I have now shot a short sample of my inconsistent focus problem and will speak to the local service centre.

Cheers
Rod
 
The video has been removed from my 09-18-2012 10:28 PM post.

The observed "bounce" was found to be a consequence of engaging Push Auto whilst AF was on.

Conclusion : Two approaches to focusing that may not be compatible one with the other.

Both functions seem to work fine when engaged separately.

So that is the way I will be using the camera going forward.
 
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Regarding the Apple "problem", it's being reported all over the place that there's a "purple cast" to some photos. It's causing some internet hysteria... the dreaded "purple haze! Oh no!! It's flawed, how could Apple have possible released such a substandard product!" Problem is... the iPhone 4S reacts the exact same way... same purple cast. So does the Galaxy S III. So do other phones.
http://www.cnn.com/2012/10/10/tech/mobile/iphone-5-purple-haze/index.html

Why wasn't there a big outrage over those other phones? Because ... well, sometimes, something just "sticks" and people get all up in arms about it. And when Apple says "well, duh, don't point it directly into the sun", people get furious -- they want a FIX, darnit!!! FIX IT!

But there's no fix because there's not a problem. It's a lens flare. Don't let the bright light hit the lens, and you won't get flares.

Is this situation like that? Not necessarily -- I think Rod's camera might indeed have a hardware issue if it's actually "locking" focus. But in general, the AC160A and AC130A work. No they're not quite the same as the AC90 or HMC150. Bigger longer lens, bigger glass. It behaves as it behaves. If it works for you, buy it. If it doesn't work for you, move on. But they've evaluated it, they've made the changes that they can make (adding the very useful turbo assist), they've explored ways to get better performance (relying on the area focus, for example) and they've made the suggestions as to how to work with it.

There are lots of users here, in this thread and elsewhere on this forum, who are working just fine with the camera. There are some folks for whom it just doesn't work the way they want. What can be fixed or adjusted, has been fixed and adjusted. It is now the product that it is. And it does work, and we have lots of examples of it working. And in low-contrast scenes it doesn't work all that well. That's true -- no autofocus system enjoys low-contrast scenes.

Best of luck, Rod, I hope the service center can find out what's going on and assist you.
 
Rod...

Tomorrow, I will do a 40 times "close object/far, but not too far object" test along a fixed arc so we don't have the added variable of different pathways going back and forth.

I shall be very surprised if the test reveals ANY focus-lock-ups.

If the results are as expected, this will reinforce your defective camera theory.
 
By the way, kwkeirstead, thanks for your diligence in trying to help another member get to the bottom of a problem. That's DVXUser spirit, right there!
 
Hi Karl, Barry and others,

Firstly, it's good that we continue to provide help and resource from this forum, long may it continue! Karl thankyou for all the stuff you have experimented with and are continuing to do so, sharing makes this forum work.
I have also now produced some tests which I would like to share with you shortly. They show the lock-up clearly as well as generating random results. I chose 8 metres and 1.8 metres on a grey day in constant lighting that kept the lens wide open to avoid any DOF bias. Reviewing this I now do believe my camera has a problem and it is possibly nothing to do with the 160a.(other than it might have a fault)

When I put this up I would greatly welcome feedback on any similar trials, before I send it back. (Service agent is on the other Island and is a bit of a pain as it is 100 of kms away and over the cook strait!)
Look forward to hearing back.
Cheers!
Rod
 
Hi all,
Here is a video of my lock up issue that I have been wittering on about. Please watch to the end (4.24 mins) and I would welcome some objective opinions particularly from Jan, Barry, Panasonic and anyone else that may be able to give a technical view. The question is: is it broken? http://youtu.be/nilQT3B3xtQ
 
Hi Rod

Exactly what my 130's used to do ..however it doesn't do it in bright outdoor lighting and it only does it at a high zoom. Did you try a quick zoom back and then forward again..I found that sorts out the issue is is very workable...I swung over to a reader at a lectern in a Church and the focus locked up just like that, but zoom out first and then pan and zoom in and there is no problem ..it nails focus PDQ This is the reason why Walter's test showed no problem cos he did it outside but I can't explain why it locked on the horses video? I guess the really simple solution is to simply zoom out before changing the camera angle..I'm pretty sure if you zoom out from the couch and swing over to the fruit and zoom in, it won't lock up at all!! That was my solution anyway..Probably something to do with low contrast and high zoom that the AF struggles with?? I'd be interested to know if you have the same lockup if you zoom out first and then zoom in to the new target.

Chris
 
Right Rod/Chris...

This pinpoints exactly what I have never been able to replicate. No point me doing any more outside testing. But, I will try to replicate your indoor findings.

But, a big question that remains for me is whether the "horse/tree" recording demonstrates focus lock-up or possibly something entirely different.

The Field/Stable screenshot could be related/unrelated.
 
Hi Guys,
The video is now been referred to our Panasonic service company here in NZ (who have an absolutely first class reputation among users and retailers here) and I await their evaluation.

Chris, I was hoping your report was due to them being un-modified 130's( I know the ND issue didn't work well for you in your application either though, and you ultimately parted company with them.)

Karl (do you prefer Walter?) . I did notice in your shots on another thread, of the anchor and Church, that your focus definitely did not achieve infinity on the Church until you put some movement into the camera-

On ELN614's shots of the standing horse and post, I didn't see any problem with that performance, and think that was a matter of extreme contrast as I mentioned earlier . The situation was extremely challenging. The post snapped in nicely when its contrast /luminance range nearly filled the frame. I wouldn't mind gambling that the WFM covered the full 0-109 on the horse /field but was a significantly narrower range for the post. Doesn't explain the barn though.
 
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Hi Rod

I actually specified ac-130 meaning they were original models not the upgraded 130A ...you brought the already modded camera ..Both mine never had a turbo focus button!!

Hope the service guys sort something out for you!!

Chris
 
Rod.. I go under any of three names: Karl, or Walter or Woof (my German Shepherds both called me that).

Interesting you should pick up on the anchor/church test where it could well be that a small jiggle toward the end of the arc bypasses the problem but I think that test was flawed in that my arc back and forth was not consistent.

There were too many variables at play. a) lack of consistency in the arc taken to get from the anchor to the church b) possibility of use of an approach that went through high contrast scenery one time and lower contract scenery the next c) variability in the smoothness of the approach

I will do an indoor 2 meter/6 meter test using small objects, zoom over 50, open, fixed arc, and make one recording using fast arc travel, another with slow arc travel.

Now that we are in the weeds on this, the stay time at either object can be the time for the red arcs to show up OR the distance meter to stop.

However, I did notice the other day that you can get red highlighting, only to have the camera continue to hunt and cause the red highlighting to back off and then come back on. I saw clearly that it was changing focus during this time so it seems you don't actually have a lock-in at the time you get red highlighting the first time. This tells me I need to wait for the meter to stop to get realistic focus lock-in timings.

All of this behavior is very characteristic of servomotors. You need very sophisticated electrics/mechanics to avoid overshoot - it requires anticipation and non-linear deceleration. We are starting to see this in the new cars where the resistance to forward motion increases with remaining distance to an object. In theory, you never get to the point where you are faced with a sudden halt. Clearly, they pay a lot of attention to avoiding overshoot.
 
Karl it is then! ( woof -that is funny!!! I will leave that for your dogs as a "pet" name! )

When you do your test could you add another visual check? and that is to carefully watch the distance meter when swinging from far to near. The reason I mention this is that on the orange lock-up shot where I tapped the camera and it flicked immediately back into focus, on the lock-up I am pretty sure that the meter was reading infinity: It was as if the lens goes to infinity , then pulls back- only occasionally doesn't. Just another parameter for you!

Seriously, I hope you can't reproduce any of this, as this is an amazing camera and I would love to hope this is a fault on mine only that can be fixed.
Anyway our NZ PAnasonic service people are the very best and they will advise me in due course. and thanks for your continuing research.
Rod
 
More video . again focus is slow.
As Jan said the camera has been mechanically designed to be slow to get focus and these results should be expected at anytime you are using auto focus.
 
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