AC130: Video footage of the Auto Focus in action

Rod, great news! Sounds like they identified the cause and can act on it. I thought it sounded like a manufacturing issue.
 
I too, have the understanding that "the AC160/HPX250 have the same AF system". If this is indeed true, then one would expect to see an HPX250A.

If not, why AC160A but not HPX250A?
Because there is an HPX250-ish... it was a firmware update that was issued at about the same time, that added the turbo autofocus capability. The HPX250, being the more expensive camera, apparently has the ability to have reprogrammable eproms in it, whereas the less-expensive cameras didn't, and needed a hardware change to implement the upgrades.

So the answer is, the HPX250 has received the same updates that the AC160A and AC130A received.
 
Updated Info,

Following Barry's comment about the firmware updates, I loaded the newer firmware in my HPX250. Although I don't want to burden youtube with one more boring video, I can report that the autofocus behavior changed, as in more responsive (less apparent damping). Now the updated HPX250 responds roughly in between the HMC150 and the older firmware HPX250. Also, I don't see the same freezing when fast panning at max zoom, seems like it keeps up with the scenery change.
 
Hi Terry,
Hey, no problem with boring test videos on this forum! It's interesting to note that the update made some changes.

I also loaded up the latest firmware on my 160A prior to my tests , but it did nothing to change my problem. But as we know speaking with data is the only way to analyse a technical issue, opinions are opinions and can be argued forever, but testing and data ultimately gets down to the issue. (and in my case has proved my specific camera has a now identified and correctable fault.) So thanks for the feedback.

Cheers!
Rod
 
I'm posting this to complain about the notion that the focusing problem is due to "the laws of physics" given the zoom range and high pixel count.

Bull! ... I have a PhD in experimental Physics, and worked on a Nobel Prize winning research discovery. The zoom range cannot be an issue given adequate servo control, and the high pixel count only adds to the information necessary to achieve focus.

The problem has to be in the software architecture or CPU processing power. I use an HPX 250 in autofocus mode and find the autofocus similar to (or better than) an HMC150 or XH A1. As I understand, the HPX250 shares the same lens and imager, but different signal processing and design groups (hence different CPU hardware and software designers). Theoretically, software limitations can be fixed, but at this stage I doubt it would happen. Hopefully new cameras will autofocus properly, since I'm sure Panasonic is aware of this shortcoming.

After more research it looks to like it is being narrowed down to the hardware unrelated to the lens but rather the CPU chip or the software on that chip.
I wonder if the "A" upgrade replaces the chip or software on it. DOES ANYONE KNOW????
If they did then this truly explains the reasoning for the very quick update they did.

Terry if we were to get you two dead camera one non-"A" and one "A" would you be able to identify the chips on the camera? (I am sure service manuals will identify everything) and then access the chip and "dump" everything off it?
 
OK, my HPX250/ HMC150 autofocus test is now up on youtube...
Thanks so much for running this test, and sharing. This is the exact same issue I was faced with in the times I've used the AC160 now. This test was very informative and valuable for me to see.
 
@ELN614
I have previously questioned if the AC160 and HPX250 control systems were similar, but for now I am going to assume that they are. So this is now my current theory: The HPX250/AC160/AC130 series was released with a relatively slow (highly damped) autofocus servo. We all shoot in different environments, so the results varied. In my world, it meant more stability on fixed targets so I was happy, but if you had a fast moving target it could mean disaster. Others used only manual focus and didn't care, and additionally some cameras were defective, like Rod's.

Ultimately, I think the autofocus was slower than "normal" and Panasonic responded by updating the firmware to make it faster and also add features. As Barry said, the HPX250 could be updated by a software download, but the AC160/AC130 needed a physical chip replacement, hence the A model.

Again, all of my comments are my opinion. I could never know for sure unless I had dinner with the Panasonic R&D director and shared a few good bottles of wine.

@Snowleopard
thanks for the comment
I have come to realize that this equipment is so important to all of us, yet there is so much more to it than you can find in a spec sheet. Barry and this site has provided a lot of valuable info to me, and it is a privilege to pay back what ever I can.
 
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Well, we may never find out what the "A" upgrade included.

As I pointed out in the discussion group "I love my AC160", it's unlikely any company would go to the trouble of putting out a new release to address just one issue, so, chances are the "A" model has a bunch of enhancements.

When I do the math, it seems that anyone having spent $5,000 on this camera will not mind another $300-400 so they can "sleep at night"

I do mostly everything in manual, but figured what the heck and so I sent my unit in and had the upgrade done.

I buy all kinds of software and do the same (upgrade), just in case and so I don't get too far behind. Vegas Pro 12 is an example - much improved in my view over 10 (I did not go for 11 so have no clue what was in that release).
 
Hi all,
In the interests of all who have been testing and those who have made contributions to this thread, here is the latest test I was asked to carry out-one of many I have set up to get to the facts here. http://www.youtube.com/watch?v=BZdwaoncge8

Terry, Walter (Karl), Chris, and Eln614 who started this thread- (thankyou), and anyone else that is interested: I make no judgement or opinion on what is going on here or or why - this is factual data, forming part of the trials which confirmed my camera was faulty . My camera is now awaiting repair under warranty. When this is fixed it will be the finest value for money camera, I have ever purchased.

It is worth repeating that I never had the hunting that ELN614 had. My camera is 160A and ELN614 was 130. I can only assume that the "A" upgrade cured this. (but it is an assumption only, as I never owned a 130)
Cheers!
Rod
 
I think I am going to make Panasonic fix my 130. I think it's got a problem no matter which way you cut it. the footage shows it's lack of ability to focus at times.
 
In the interests of all who have been testing and those who have made contributions to this thread, here is the latest test I was asked to carry out-one of many I have set up to get to the facts here. http://www.youtube.com/watch?v=BZdwaoncge8

That's a good test and the camera should certainly gain focus 100% of the time. I'm skeptical it's an actual one-off fault, however. Regardless, it might give Panasonic enough ammo to release another firmware update.

I had an obscure issue with a Roland Synthesizer in the early 90s that Roland was convinced was a fault with my particular unit. I eventually proved it wasn't and a new firmware was written in Japan. The process, did, however, take several months and I was without my synth a couple of times while it first had the main board replaced by a local repair company and then was sent to Roland Australia. In those days, updating the firmware required replacing a chip.

Good luck with the repair, Rod.
 
The only spec you ever read about autofocus is "yes" or "no", but we are all finding that there is a lot going on in actual performance observed in our various environments. I'd like to commend those who started this 30 page thread and rose above the "shouldn't need autofocus" comments to a real tangible test of autofocus.

Rod's near/ far test dosen't measure every factor in an autofocus control system, but it is an undeniably scientific and useful test (I agree with Mike). First it detects any circumstance that autofocus fails on a viable target with good lighting and contrast, and it reflects the "damping factor" in the control system as we watch how fast a new target snaps into focus. All feedback based control systems have some setting that limits just how fast they respond. If a system responds too fast, it can become unstable, and too slow, less useful. Every designer has to figure out the optimum for stability and performance.

I'm going to now refer to the near/ far test as Rod's test. It is a good standard that we can test various cameras with and learn more about their control dynamics. It is amazing to me that I used the HMC150 and HPX250 in real work, but never noticed this "damping factor" difference. I did notice that the HPX250 was more "stable" and I now understand that it is a consequence of the slower response. So which is better? ... not a fair question, they just respond differently. Now as I pick a given camera for a job, I have more information to make an intelligent choice, just like CMOS vs CCD. More information is always better.

Now for one more thing, since I have been thinking about video autofocus. This is a humble suggestion to Panasonic of a useful and easy to implement software control that will serve some of us. Suppose there were three menu based setting that defined 1) near focus distance limit, 2) far focus distance limit, and 3) autofocus response rate (damping factor). The settings should go to defaults when the camera is power cycled. Settings 1 and 2 would be great for event work such as a stage 60 to 80 foot range. Yes, a user definable damping factor could make autofocus unstable, but it would give ELN614 a fighting chance to tune the camera to his requirements.

Rod, as I get time, I'll try to post your test with the HPX250 (updated firmware) and my new AC90. We will all be interested in your AC160A after it returns from Panasonic.
 
Rod, as I get time, I'll try to post your test with the HPX250 (updated firmware) and my new AC90. We will all be interested in your AC160A after it returns from Panasonic.

Hi Terry,
I think my last test highlights the issue I have asked Panasonic both here and directly several times, which is:

" What extra info do the lens servos receive when pressing the turbo button during a focus lock that they don't already have? --nothing has changed-contrast, distance, lux, focal length, static target, aperture, shutter speed are all constants. But on a focus lock-up (see my last test video), pressing turbo, it snaps in every time, and fast! "

Now, given that my camera is considered to have a fault which is creating this, I am still curious as to what is actually happening: I cannot speak with data here but if I was to theorise, I would guess that pressing the button sends a "pulse" of extra energy to the servos- which recomission the auto focus mechanism with some serious grunt.

I repeat, this is instant, which surely negates the argument of lens mass/dynamics etc. It can focus very quickly indeed when pressed (pun intended) Have you any thoughts on this?
 
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I cannot speak with data here but if I was to theorise, I would guess that pressing the button sends a "pulse" of extra energy to the servos- which recomission the auto focus mechanism with some serious grunt.

No. At the point of lockup the camera has given up (for whatever reason) trying to focus. When the turbo focus button is pressed the auto focus system is told to try again, but this time it's using different parameters and a faster feedback loop. It's basically the same thing that happens when you move the camera back to the far object (except for the speed change). The algorithm is also quite likely slightly different during this mode, since the designers know at that point that you are definitely not in focus, whereas at other times the software needs to decide that for itself.
 
I like the theory ". . .The algorithm is also quite likely slightly different during this mode"

You would think that in the normal mode, once the camera decides to "give up" that it could invoke Push Auto on its own.

The designers may have figured that auto-linking the two modes might get you into a loop.

Maybe a small change where the linking is done once only would help.
 
You would think that in the normal mode, once the camera decides to "give up" that it could invoke Push Auto on its own.

The point is that in auto mode it can't be too aggressive or it will be prone to hunting. As to why it's giving up is still a mystery to me. Either something about the signal is tripping the "In Focus" flag or the perhaps it thinks the subject is too close. In that situation, the last thing you want a video camera to do is constantly hunt from one end to the other.

It's also possible that something with Rod's particular camera is faulty. For example, the focus motor might be drawing too much current which is detected and the motor is shut off to protect the drive circuit. This is not high on my list of probable causes.
 
130/160 owners please do me a favor.
put your camera on a tripod and set it on auto focus
shoot an object like a house at least 50-120ft away. Make sure no other objects are in the shot which are less than 30ft away.

zoom in and let the camera find it's focus. then note the distance. now zoom out wide and as you zoom out note the focus distance the camera is telling you.
as you go completely wide with the far object in the center... what is your final "distance" (try not to choose trees since it can move with wind)

If your camera is working like mine--- it will read between 1-4feet.
What does yours say?
 
Hi, I did it twice. Zoomed in 88 ft, then fully zoomed out, after a lot of hunting, it goes to infinity. I remember seeing a clip of a barn where ends up saying a few feet.
 
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