ALL: Does this look like an Autofocus Bug to You?? -- Video Clip

Lou Bruno said:
All about the camera's focus:

http://www.youtube.com/watch?v=I0to4OqIrBg&feature=related


More:

http://www.youtube.com/watch?v=PY4o_U0y00o&feature=channel
Click to expand...


One important focus feature that those videos overlooked is the FOCUS ASSIST feature. I've found it to be invaluable to use, as it makes using manual focus so much easier.

I shot a Kick-Off reception for the re-election campaign of a local politician this week, and FOCUS ASSIST made it so easy for me to confirm that everything was in focus, exactly the way that I wanted it. The reception was also held in a dimly lit private room with its own bar, at a local restaurant. My AC-130 handled the poor lighting conditions very well in my opinion. I used f/2.2 for the Iris, to get good depth of field. Set DRS to 1, and added 3 dB of gain. Used the factory F3 Sparkle scene file. I recorded it in 1080/24p, but ended up exporting it from Premier 5.5 to 720/24p to post online. Did little in Premiere other than to use LEVELS, and do a slight SHARPEN.

I got lazy, though, when it came to setting the White Balance. I had the camcorder initially set for Auto White Balance, and the skin tones looked so very good on the LCD, that I decide to not try to fiddle with it any, and just left it on AWB. As much as the AutoFocus features of this camcorder may have issues, the Auto White Balance feature on my AC-130 is easily the best that I have ever used, either in a camcorder or still camera. It was good enough that I did not bother at all with it in post.

Here is how the video came out:


 
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I would love to see the HMC-151 with the same optics as before, but all the qualities of the AC-160 like framerates and pixels... But probably not gonna happen.
I dont need X22 zoom, but good auto focus, yes...
 
Nope, the HMC150 upgrade has already happened, and it's the AC130/AC160. The AC160 has better optics, better audio recording, better outputs, better LCD and EVF, a dedicated iris ring, better zoom range, 2nd card slot, etc.

And the autofocus (as I personally have attested to) is still very good. The HMC150 had issues, too. We still use both the HMC150 and the AC130 and when shooting 24p modes, the AC130/AC160 is as good if not better than the HMC150, plus I have more control over how I want to focus (area control). In comparing 60p and 60i modes, they still are not a night-and-day difference in my opinion, based on my personal usage. The HMC150 did handle 60i better, but 60p to me seems like a draw between the two.

As a side note...an HMC150 upgrade would not get the designation "HMC151" anyway....the trailing number increments on Panasonic models (and other brands as well) is used for region differentiation, not upgrade increments. Panasonic has used trailing letters in the past (DVX100A, DVX100B, HVX200A) but also has used full 10-digit increments (HMC70 become HMC80, HPX300 became HPX370). This is important to remember if you see someone selling an HMC151 because it is not an NTSC (Americas) camcorder but actually PAL (Euro). If they had retained the HMC150 body style, it would have probably been called the HMC160 or HMC170 or HMC180....something like that.

Long story short, don't expect to see the HMC150 body style, optics or sensors revisited, at least not anytime soon. The AC130/160 is the current upgrade path from the HMC150, and the HPX250 is the path from the HVX200A and HPX170. For everyone who prefers the HMC150 over the AC130/AC160, the current upgrade would be a 2nd HMC150. :)

EDIT: I meant to put a note in about the focus assist on the AC130/AC160.....last weekend I had a guy shooting on the AC130 who had NEVER touched the camera before nor any camera like it (just consumer cameras), so he had ZERO experience shooting on a real camera (he's not a video producer, but he was available and the shots were pretty simple, and he's been bugging me to bring him along on a shoot sometime). So basically, he's as much of a n00b as anyone could be. He arrived late, only 15 minutes before shooting. I showed him the basic controls, made sure he understood that the focus and iris would be MANUAL and required CONSTANT supervision. I turned on the focus assist (red outlines) and explained what it meant. 5 minutes later we're recording and his footage was sharp all along the entire range of zoom from full tele to full wide. He said it was easy, said "I don't know if I'd ever need to use auto focus." It's as good of a testament to this camera's focus capabilities as you'll ever hear. I had a seasoned pro shooting at the same time on an HMC150 and he was running autofocus but had to turn it off (1080p24) and go manual because he said it kept losing focus.
 
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I have just had news from one of the importers of Panasonic in DK that Panasonic have announced a software upgrade for the AC-line that includes FASTER AUTO FOCUS!
So maybe they have finally gotten their act together.
Jan, if you could verify this it would be great!

@ scapsinger, that sounds really good.
I am renting a AC-160 this month and will shoot 3 performances with it, so I will try it out as well as the focus assist. I will try to come back with the results as soon as I can.
About upgrade of the HMC, then I am aware of the succesor being the AC line. I think it is a shame, as I, and my guess is many others, will miss the sleek and lightweight body of the DVX100/HMC 151 (I didnt mean that the 151 would be the upgrade, I am living in Europe, thats why!), and it is a shame we dont have the option. Of course we have the option of buying the 151, but still it seems to me that there are significant improvements in the AC-160 that could have been brought over in a upgraded version of the 151.
 
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That is one thing about the HMC150 that was nice, it was light as a feather. The AC130/160 is much weightier. Some people have mentioned it gets a little aggravating after a full day at a wedding or other handheld event. I haven't had the opportunity to find out, but I know my rig about 5 or 6 years ago for weddings consisted of a DVX100B with NRG light (heavy S.O.B. but an awesome light) combined with the necessary XLR battery belt (heavy S.O.B. as well) and the DVX100B wasn't a total light weight with a full sized battery anyway. With an LED light and no battery belt, I've still got more freedom of movement on an AC160 nowadays than I did a few years ago with that old rig.

Going to the HMC150 and an LED light was nice, but I think most people will find the additional heft of the AC160 to be helpful in run-n-gun situations anyway as it's got a bit more inertia to keep in from flopping around in your hands. Or you can buy a shoulder rig of course. :)

Good luck on your shooting with the 160, let me know what you think. That focus assist is really amazing. I find that I have to toggle it OFF if I'm shooting on the long end of the lens from a distance because the red outlines can really mess with my ability to judge exposure sometimes. The BEST thing though is to put your EVF on black and white mode and use that if you can, because then when you have the focus assist turned on you ONLY see the red outlines against the colorless image in the EVF, makes focusing like a day at the beach.
 
Lars Gregersen said:
I have just had news from one of the importers of Panasonic in DK that Panasonic have announced a software upgrade for the AC-line that includes FASTER AUTO FOCUS!
So maybe they have finally gotten their act together.
Jan, if you could verify this it would be great!
Click to expand...
I would ask your guy to re-verify that information. Panasonic has announced a firmware upgrade for the AC160 (and only the AC160) will be forthcoming, but it had nothign to do with faster auto focus, it was going to add 1080/60p (using the new AVCHD 2.0 codec).
 
LanceOregon said:
One important focus feature that those videos overlooked is the FOCUS ASSIST feature. I've found it to be invaluable to use, as it makes using manual focus so much easier.

I shot a Kick-Off reception for the re-election campaign of a local politician this week, and FOCUS ASSIST made it so easy for me to confirm that everything was in focus, exactly the way that I wanted it. The reception was also held in a dimly lit private room with its own bar, at a local restaurant. My AC-130 handled the poor lighting conditions very well in my opinion. I used f/2.2 for the Iris, to get good depth of field. Set DRS to 1, and added 3 dB of gain. Used the factory F3 Sparkle scene file. I recorded it in 1080/24p, but ended up exporting it from Premier 5.5 to 720/24p to post online. Did little in Premiere other than to use LEVELS, and do a slight SHARPEN.

I got lazy, though, when it came to setting the White Balance. I had the camcorder initially set for Auto White Balance, and the skin tones looked so very good on the LCD, that I decide to not try to fiddle with it any, and just left it on AWB. As much as the AutoFocus features of this camcorder may have issues, the Auto White Balance feature on my AC-130 is easily the best that I have ever used, either in a camcorder or still camera. It was good enough that I did not bother at all with it in post.

Here is how the video came out:


Click to expand...

Good color and sharp. But I was really put off by the blurring hands for the first guy, and the blur when he moved away. Obviously this is because of the slow shutter. I really do not see the merit of using 24P when this is the result. For me, it ruined the video, and I would think this would be true for the average viewer, who never sees such blur on TV (because no actor moves his hands fast unlike in real life). Why did you choose a slow shutter/24P?
 
Hi Guys

I see this thread has tons of posts saying "you shouldn't be using auto-focus" and I do find it rather strange that the camera operators are now to blame for the drifting focus rather that the fact that the autofocus has a fault...yes, some of us DO use autofocus and be that good or bad the bottom line is that the cameras do have an issue which seemingly is being ignored and "worked around" rather than rectified. Sure I can use manual and lock it down BUT I shouldn't have to!! If you drive out the showroom in your brand new car and the radio keeps drifting off the station so you are continually having to re-tune it..would you be happy?? I'm quite happy for the time being to switch to manual to stop the cameras from drifting but that still doesn't mean that the issue still shouldn't be rectified!
My HMC70's and HMC80's and HMC150's never had the issue so it's not a Panasonic "quirk" at all. Workarounds are very much appreciated but it still doesn't mean that Panasonic doesn't need to fix it.

Hopefully they will come up with a solution

Chris
 
ChrisHarding said:
I see this thread has tons of posts saying "you shouldn't be using auto-focus"
Click to expand...

I've actually been trying to make the point that the auto focus - as far as we've been using it with our shooters - has only been marginally less effective than the HMC150, and only in progressive modes, and really only at points toward the end of the zoom range. Overall we're happy with the autofocus and have been getting results consistent with our HMC150 cameras.
 
I just finished the 1st half of a wedding and no focus issues BUT it seems like the autofocus is quite happy with short clips and moving objects..the problem occurs on a static camera when it decides, for no reason at all, to drop the focus it has had for the last 5 minutes and focus on something else in the background!! What I did today was use the autofocus button to lock in the correct focus and then, snap the cam into manual...it's a bit of a workaround BUT it stops any hunting!!!
I'm off to the reception shortly so I'll try the same trick when I have the main cam pointed at the lectern...get the focus good and then lock it down!!! Both cams are very happy at wide angle and autofocus but any amount of zoom makes them go crazy!!

Chris
 
I have never used autofocus because of the very trait mentioned. Autofocus gets bored when nothing happens and it is sods law that an automatic tweek check will happen at the very moment you want to use the shot. Part of me agrees that if the facility is available on a camera it should work but the other side thinks that you cannot ever rely on it for a paying job, there is always a doubt. Skill is needed to focus but then that is what the job of a professional camera operator is all about.
 
Looking back at the original dedication ceremony, it seemed to me one of the places where the autofocus lost it was when the blue drape was being removed to expose the black background.

As someone pointed out, the system did recover quickly. Its probably easy to edit out the few frames.

I suspect it was the movement of the blue drape that caused the problem as opposed to the fact that there was a transition from blue to black. Only way to pin this down would be to repeat with a less dramatic color change and see if there is a difference. Or, remove the drape slowly.

I am going to re-visit the ice skating clip, which to me was an amazingly good job of filming to see what focusing issues were observed during that recording.

It would be interesting to try to catalog the kinds of situations that cause autofocus to wander, it might help Panasonic engineers identify possible solutions.

I must say that early experimentation with a new Manfrotto electronic focus puller that I just installed last week seems to have simplified manual focusing for me. I like the way the focus assist kicks in on the camera as you dial up / down focus. I don't seem to have mastered avoiding pushing the green dot toooo far with the result is I have to back off a bit and then approach the green dot but not actually touch it.

Anyone have variations to manual focusing that might work better then the two-step process I have been using?
 
I did two weddings over the last two days and without a doubt the problem seems (strangely) to manifest itself when the cam is maybe zoomed in at least 4X or more and fixed on a scene. The autofocus tends to almost get "bored" abd decides to look for other areas to focus on. Shortish clips with different subjects seem to cause absolutely no issue but put the camera on a tripod and point it at one spot and the focus issue starts!!! The first wedding ended up with a soft image in parts cos the cam decided after a few minutes to forget the bride's face and rather focus on some distant trees !! That was a disaster!! At my second wedding I tried the new tactics and they worked 100%
OK: I have the AUTOSW AF option turned off now but you can still leave the camera body switch on AUTO
When I have a long tripod shot of the same subject (wedding ceremony) especially without much movement I switch the cam body switch to MANUAL
I then frame the shot and hold down the Push Auto button to allow the auto function to lock in the focus and then let it go so the focus is locked down in manual

I had no focus issues at all with the static shots locked down!!

I think the ice skating clip didn't have as many issues as expected mainly because the subject and camera was moving!! It seem this issue is at it's worst with static scenes and a static zoomed in camera!!!

I know it's a work around but I would definately lock the focus on any static shot now !!

Chris
 
Sounds like good advice. I think Jan had suggested a procedure somewhat similar to the one you have evolved. I will try this.

I am wondering whether there might be a timeout on long clips where autofocus does a reasonable job and then, as you suggest it 'gets bored'. If this proves to be true, it may be that it is also losing via some timeout it's area of focus which might account for why it goes for the trees.

The "black box" approach you are taking is a good one for "connect-the-dots" puzzles like this one.

You have given a good hint of how to experiment i.e. start at 4x then repeat at 2x (less of a problem?) and, if so, does it behave as we might expect going in the other direction from 2x to 4x and beyond?

It would be interesting to see whether the variations are linear or somewhat exponential.
 
My mate in the UK Chris Hewitt emailed me this morning and mentioned that while using AutoFocus having "Face Detect" turned on helps the auto focus lock onto people especially where you have a wedding situation and a tight shot on the happy couple!
Anyone else have Face Detect turned on, apart from Chris?? On my HMC80's I used to keep FaceDetect turned off but if it assists in stopping the camera hunting and drifting off focus then I'm all for it??
Do you have yours on or off on your 160 or 130????

I can safely say that shooting full wide I don't think the camera has lost focus at all even on full auto BUT my 2nd camera is almost always hand held and moving which also may help. The focus issue definately gets worse as you zoom in..at the wedding I shot yesterday apart from locking focus I kept all the shots a little less tight and that also helped. So far I have only had issues on static cameras pointed at a fixed position..like a lectern. At Friday's wedding, the first one this weekend, I had a tighter shot and AF was on and when a speaker walked away from the lectern the LCD immediately went totally out of focus ..really blurred despite the fact that the wall behind was about 5' away and the lectern was still in the shot. Locking down the focus in Manual made things easy!!

Sorta 2 x and 4X zooms still seem to be fine but everything falls to pieces if you go any tighter and the AF definately works correctly for a while but then the boredom bit comes in play and it decides to look elsewhere...If face detect works I wonder if it would be fast enough to react with a person walking in and out of the shot ...it's normally a few secons before they actually talk!!! but if it does indeed help the AF it's a worthwhile help tool to have on!!

Chris
 
ChrisHarding said:
My mate in the UK Chris Hewitt emailed me this morning and mentioned that while using AutoFocus having "Face Detect" turned on helps the auto focus lock onto people especially where you have a wedding situation and a tight shot on the happy couple!
Anyone else have Face Detect turned on, apart from Chris?? On my HMC80's I used to keep FaceDetect turned off but if it assists in stopping the camera hunting and drifting off focus then I'm all for it??
Do you have yours on or off on your 160 or 130????

Chris
Click to expand...


The problem with using Face Detect is that using it also automatically puts you into Auto Iris mode too. So you no longer have manual control over your exposure.

So Face Detect is not just for focusing on faces. It is also automatically adjusting your exposure for the faces too.
 
scapsinger said:
I've actually been trying to make the point that the auto focus - as far as we've been using it with our shooters - has only been marginally less effective than the HMC150, and only in progressive modes, and really only at points toward the end of the zoom range.
Click to expand...

Well, but there are no warnings in the User Manual or in Marketing literature that shooting in progressive modes or using the great new long zoom range ( which is highly touted ) will cause any drawbacks.
 
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