AC130: Video footage of the Auto Focus in action

Hi Chris, yes the horses clip. Frozen auto focus example. I will hang on to my other Sony for now-funds are too tight to risk a disappontment. As I have said many times I love this camera and it is a world beater for the money, if it is the long lens causing this , personally I could have done without it and had something that was more responsive. But I don't shoot wildlife and I could see it being very good for that where one would certainly be using manual focus anyway. I guess it cannot be all things to all men ( and girls of course!)

And the V8 racing- hope all the gears in their boxes work without them having to adapt their style!! hehe!
cheers!
Rod
 
Around the end of October I will upload a few more clips. I have many many hours of footage to go back through, but I have still have another 60 horses to tape and edit. I might try to reenact the same 'pole - horse' example. to see how long it will take to focus on the object that takes up 75% of the framing.
The JVC 600 is coming out soon so I will have some time to see what people think before I pull the trigger on that one. (to replace this one for horses)
I plan to keep the 130 for my deposition work.. it works great for it. I am always completely in manual during those tapings.
 
Hi ELN614. Your frozen focus on the horse and the later stable still is exactly the problem I see. The one with the post I suspect is caused through the camera focus being prioritised by the massive contrast on the field and horse and virtually zero contrast on the post until it fills the frame. This camera definitely does not like flat contrast when auto focussing. I can live with that, as that is typical of most cameras that use contrast as a measure.

But the stable shot is just unnaceptable performance. That is a high contrast frame filling shot-no excuse not to get that right on auto. Makes filming horses in movement a bit of a challenge!

If you repeat this shot it would be interesting to use the function button to move the square zone marker from the horse to the post. I have tried this on high versus low contrasts and it works most of the time. Once the zone button is pressed, the zone can be used as a spot meter/ focus. For horses in flight it would certainly be good to track the movement if it works. M

Karl, have you used the function button for zone focussing on your sports vids at all? do let us know how that works out.
Cheers!
Rod
 
Here's what I do re the Function button. Set to Focus\YGet. When you start up the camera you get a crosshair (maybe you get that anyway) but pushing Function gives you a "spot". I can't see the advantage of moving that anywhere (keep it in the center) for recording fast moving objects.

Does it give better focusing when you have indicated a small area? Perhaps it confines the searching for contrast to that small area and if so, then great.

Otherwise, moving the area to some non-central location would have the objective of testing the lighting level at certain parts of a non-moving scene (the Y-Get part of the function) because of the dual option selected.

In any case, I rely on waveform.

I have no clue how to make effective use of the 2nd view that follows waveform. So what if it tells you what the various color angles are, I don't know what to do about it unless perhaps modify the Scene file I happen to be using.

So many things to learn about with this camera.

But, I am really, really curious about the seemingly never ending "hunting" debate re auto focus.

What counts is whether the camera keeps things in focus.

Take a ride in a large airplane and watch the wing flaps during landings. It's common with some aircraft to see them hunt (up,down) rhythmically, but with each 'correction' there is not enough time for anything to happen - it's just the way the servos operate.

I remember industrial motorized valve controls where the valves were, due to their mechanisms, sticky - it was better to let the electronics integrate the errror and then make a correction. Otherwise, you would end up oscillating (too much/too little). This is why heating and air conditioning have uppper and lower dead zones at whatever temperature you "set".

Maybe, the camera "hunting" is actually just "scanning" and unless/until something is "found", no corrections take place, so perhaps we should not worry about it.

I have yet to replicate the scenario where the camera gets "bored" and sets its focus somewhere else. I did a test with objects at 30 feet and 80 feet and when the near object leave the scene, only then did the focus go to the distant object. When the subject re-entered the scene, the focus immediately returned to the subject.
 
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Yes I made the same surmise on the smaller area on the function square enabling a quicker and more stable focus and exposure- use it like an SLR follow focus spot meter. However my trials didn't confirm the theory.

The question of hunting when a camera is locked off on a non moving subject is something to be worried about. This whole issue was originally raised by someone who was recording a commemoration presentation I believe. The focus on the speaker drifted in/out for no reason. This is not acceptable.

However, like you, I haven't had that problem- my issues are with the inconsistency of the focus system. Yesterday I replicated your focus trials using two well lit subjects but at 10 meters and 3 metres. I also used the centre function square to ensure a tight and repeatable trial . The results were out of 20 swings between the subjects. 13 took less than 2 seconds to focus-. 4 took up to 7 seconds- 3 wouldn't focus at all and completely locked. These I eventually cleared with the turbo focus button and they snapped in immediately- and I mean immediately.

This takes me back to my original question: Nothing at all changed during this trial and the camera was tripod mounted and swung quickly, in a very short arc between repeatable points. SO what extra info was the button receiving or more likely sending, that it didn't already have? It certainly seems that the focus freezes occasionally and the button clears a memory lockup.

Some feedback from Panasonic would be very welcome on this, as it clearly is a repeatable anomaly for some of us.. Unless we hear from them we can speculate until the cows come home on what causes this random issue. (and probably be wrong !)

In the meantime I will continue to work with this otherwise superb little camera as this peculiarity doesn't affect me greatly. But that doesn't mean it shouldn't be addressed or at least explained by Panasonic..
 
Hi, Rod... Curious that I have never seen the focus freeze.

I cannot say either that I was able, from a tripod going back and forth on a fixed arc, to get differences in focus lock-in.

But, it's not altogether impossible that relative distances matter. So, I will do 3 meters and 10 meters x 20 and we shall see.

I don't think Push Auto receives anything. As you suggest, it probably sends but since the upgrade came in the form of a "kit' and probably some software to talk to the kit, I suspect Panasonic put in some extra hardware that the Push Auto talks to.

I strongly suspect the pathway to the glass is different under Push Auto than it is under AF. The fact that I was able to observe a double bounce with AF ON when I do Push Auto, but no bounce when AF is off OFF and I do Push Auto seems to reinforce this theory. But, Albert Einstein warned "In theory, theory and practice are the same, but in practice they are not"

We are talking about very sophisticated hardware/software here so it's kind of difficult to figure anything out without an understanding of the inner mechanisms. I would not see any camera manufacturer providing details on how they do this or that if such details could help a competitor.

The best advice I found in all of these discussions for me is try to work with the camera, not against it, which to me means get the camera working for you but, at the same time, work for the camera.

But, don't bang up against the limits of the camera because that just leads to frustration.

I took the route of going for very high zoom solution with a partial understanding this might mean poorer performance in low light and possibly longer focus times. I have been pleasantly surprised by the low light performance. And, not unhappy with focus.
 
Hi Karl,
Well, as I said we can all speculate on what is going on (or not) but until Panasonic give us the courtesy of some feedback I guess we will never know.

I have just watched the video of Jan promoting the new ac90. Her emphasis was very much on the amazing focus capabilities of that camera. My Sony's always work like that and with superb OIS too. I sold one of them to move to the 160A and that I suppose is the root cause of my disappointment. At more than double the cost of my Sonys I was expecting the 160a to be at least as good on the auto focus and OIS. (didn't come close, but the 160A is a much more versatile camera in every other respect).

However, as you say we can (and do ) work within the limitations and I have no issues with that. What I do have issues with, is when something does not function as it should. This is the biggest topic on this site and focussing comments occur in many other threads. Panasonic has my money now and that was my choice. I purchased this after reading glowing reviews and without trying it out (no dealers down here so I purchaed it via mail from the North Island). Also my choice.

However the 2nd 160a/130 purchase that I was going to make, is I think is going to be shelved now. My choice also. I will do what I should have done the first time round and wait to see what problems other users have with any prospective new purchase and make a judgement on what I can live with. I am getting grumpy now and I shouldn't, because I really do like the little 160A. I need some caffeine!
Rod
 
Hi Rod

My focus hunting experiences were in fact with the area function on!! I was about 10 metres from a bridal couple and zoomed in just a bit so the couple were in a sorta semi close up looking at each other and the area function grid was on the bride only! Between the couple I had a small area of trees way way around 50 metres or more in the background and probably taking up no more than 5% of the frame and also purposely out of the area grid too. The camera took around 10 minutes to decide that the trees were more fun to lock onto than the couple (despite being a minor part of the frame) and the couple, of course, went fuzzy!! If it helps the trees were dead centre in the frame with the couple left and right so having area function on didn't help at all. This scenario was a bright sunny day so there was certainly plenty of light and contrast!! After that wedding I went manual without any issues and as long as I stayed full wide, focus did behave but was rather fickle if you zoomed in a bit. At the same wedding I had a similar situation during the reception speeches!! Ok it was a dim venue but I had good CFL lights on the lectern ..in this case I was about 6 metres from the lectern and at 10 metres was a plain white wall. The lectern was sharp as a tack in auto and when the first speaker walked up it he was also nicely in focus....then half way thru the speech, he dropped his notes and bent down to pick them up so he disappeared from the frame leaving just the lectern and white wall at the back and the focus went totallu blurry!! He stood back up and instead of locking back onto the speaker who virtually filled the frame it just stayed totally out of focus and I had to manually correct it. I must admit the camera might have struggled there with the white wall so it did have an excuse but it certainly shouldn't have drifted with the outdoor setting.

The answer is very simple ...nevr use AF unless you have a moving target that really needs AF!!

Chris
 
"The answer is very simple ...nevr use AF unless you have a moving target that really needs AF!!"

CHris, this makes ELN164's work with feisty horses a bit challenging!

Your comments on the function square verify my experiences then. I thought that might be a solution to use the spot meter/focus aspect but not to be. I have just run the same 6 metre/ 3metre trial with the square on to ensure I wasn't reporting inaccurately, and again achieved inconsistent results. This time with 5 out of 20 cycles locking up. But a slight vibration of the tripod was enough to get focus to snap in.(movement+contrast?) The results are more consistent with a wider range of contrast/ colours and light, although I never achieved 20/20. But your "sunny day" scenario confirms this anyway.

Perhaps this forum is not the right way to raise this:(I assumed that Panny kept an eye on feedback and indeed have responded here before).
Have any users raised this directly with Panasonic? I would have thought that the number of times this has been raised on various other threads, that we can't all be wrong! However, I think the issue of sending a camera back would be their time involved in testing for an erratic and random non-compliance of function-probably not practical.

Oh well, I guess that unless they can offer a soft/firmware download (or some fufu dust) we are stuck with it! There is a well known saying "don't spoil the ship for a hape'th of tar. " that' s how I feel about this- great ship but occasionally the compass doesn't work- but we still have the astrolabe and I like sailing in this ship!
Rod
 
Chris... Most peculiar the bit about . . . .

"The lectern was sharp as a tack in auto . . .he disappeared from the frame . . .He stood back up and instead of locking back onto the speaker who virtually filled the frame it just stayed totally out of focus "

My chair-sitting subject also left the scene - in that test there was lots of contrasty material 80 feet away and the camera immediately picked up on this. AND, when the subject returned, the camera immediately locked back onto the subject.

So, the only thing different (aside from distance differences) seems to be that in your scenario, the camera had nothing it could lock onto for a short time after your subject left the scene BUT why did it not pick up the subject as he returned?

I cannot understand why the fact that it had nothing to focus on for a time would cause a different result EXCEPT that it might have gone to infinity and had difficulty returning from there.

Looks like more experimentation is needed.
 
Actually, I'll dig out the footage from that wedding so you guys can actually see exactly what happened...I would have expected it to recover and re-focus too after a few seconds at least!! That was the only wedding where it happened as after that I went manual!! The wedding the previous weekend was an identical day and nothing really went wrong on the focus and it behaved really well!!

That way you can see exactly what occured and maybe see ways to avoid it in the future???

Chris
 
Karl I think we have all experimented enough. A fix is what's needed. It is inconsistent certainly in my controlled trials and just doesn't work consistently in identical cycled shots. If nothing has changed then why will it not duplicate correct auto focus every time? I want it to work like the 90!

Rod
 
Hi Rod

Yeah point taken..there is ample proof of the AF not working so you don't need any more footage ..it would be far better to get a fix but I don't think is will happen..there are too many units out there..The warnings were already out before I bought my two but foolishly I ignored them..I think the answer here is a nice strong piece of gaffer tape over the auto-manual switch and leave it at manual period!!

Chris
 
HEHE! nice fix Chris- But I think I will use the gaffer tape over my wallet for a while-

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..

Thanks for the loupe info, I like your mods too- nice one.
Rod
 
Thanks Rod

When I sold my 130's the guy didn't want the shoulder rig or the loupes so I have kept them and if the AC-90 turns out to be as good as others say, I'll put them on the AC-90 LCD and an aluminium rail under so I can use it shoulder mount...The first camera will be mainly to make my stedicam rig a bit less harsh on my body... even the 130's made life a lot easier than the HMC82's as they are nearly 4kg... the 90 should be a gem on the rig and vest!!

Chris
 
Gone are the days where companies admit there is a problem and fix it. Jan and the rest of Panasonic are pulling an Apple..

"You're doing it wrong -- hold it like this instead of that -- technological advances in one part of the camera mean that another part will suffer" etc etc...

At the end of the day, switch brands if the camera does not meet your needs.
 
Hi Phil, yes the silence is now deafening! Years ago I worked for a company whos motto was, "the customer is king". ho hum- I am too old fashioned I guess---as you say, gone are the days-----.
Rod
 
I think the usual story nowdays seems to be bring out a new model?? Boy, I was so relieved when I found a buyer for the 130's (even though I lost money) and ordered a new pair of HMC82's ... They might not have as many features as the newer models but I certainly cannot fault them one tiny bit after my now 3rd pair (I change cameras every year to get a neat tax break!) Sadly the popularity of shoulder mount cameras is waning so I doubt whether a new one will ever emerge ..even the new JVC looks like an AC-160 and a 23X zoom...I wonder if that has focus issues too?? Funny, even with the 1/4" chips the video IQ is still awesome!! In fact weddings shot on the smaller chips look better than the ones I shot on the 130's ... I guess the default scene files are better??

I guess it's time to accept the camera and move on and do the focus the Panasonic way??

Chris
 
and the way is-- sometimes it works, sometimes it don't!!

Still, Jan is waxing lyrical about the "amazing instant focus " of the ac90. IE: " look folks it actually works as it should!."

Panasonic will clearly not address this issue. The 160A is really great and it doesn't go wandering off in/out of focus like the 160 seemed to, that's for sure. It just doesn't focus repeatably and reliably-IT JUST DOESN'T WORK PROPERLY!! (MINE DOESN'T ANYWAY.)

As time passes and silence ensues we will all lose interest due to no feedback in this and some of us will probably die. Then the issue will slowly be forgotten. ( shame though).
ROd
 
Rod:

This issue has been discussed many times earlier in other threads in this forum. Perhaps to the point of ad nauseam. It is not at all true that all we have heard from Panasonic is "silence". That is a most inaccurate statement.

The A update does appear to have added some nice new features, but it certainly does not overhaul the autofocus system.

As I said a few pages back in this thread, I think that the saying "it is what it is" applies here.
 
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