AC130: Focus updates anyone?

I suppose Lance is right that going from 100 feet to 6 is not something very practical. The 20 feet to 1/2 mile test probably is no better.

So, how about one of the following:

a) a row of light posts along a river walkway with a black/white card stuck to each, say 5 posts each 30 feet apart? We could try going from 1-2-3-4-5 then quickly from 5 to 1 to see what that does?

b) or, cars moving at an angle of 45 degrees to the camera face, moving at say 30 mph, 40 mph and 50 mph to see how auto-focus tracks the movement. Here there might be confusion with focus and blur as the speed increases.

c) some other suggestion.

And no rants this time about unrelated audio issues !
 
kwkeirstead said:
I suppose Lance is right that going from 100 feet to 6 is not something very practical. The 20 feet to 1/2 mile test probably is no better.

So, how about one of the following:

a) a row of light posts along a river walkway with a black/white card stuck to each, say 5 posts each 30 feet apart? We could try going from 1-2-3-4-5 then quickly from 5 to 1 to see what that does?

b) or, cars moving at an angle of 45 degrees to the camera face, moving at say 30 mph, 40 mph and 50 mph to see how auto-focus tracks the movement. Here there might be confusion with focus and blur as the speed increases.

c) some other suggestion.

And no rants this time about unrelated audio issues !
Click to expand...

The tough thing is here that there is no real definitive "this used to do this...and now it doesn't" feeling from these tests. Without the original 160 to test, its just a "feel" of if things improved which I know we're all hoping for. But sadly, I think it was "deer film" or something like that that posted earlier with tons of tests on the old 160...to me, I wish he could borrow or rent the new 160a and do the same tests and compare. That would be ideal. But you taking your time out to do all the tests you are doing is still very much appreciated and I for one am still eager to see what you think. Good luck and thanks!
 
If we figure out some standardized tests, I would be willing to volunteer my AC160. In other words, kwkierstead, shoot something you think I might be able to duplicate fairly easily! Perhaps have two people standing 5 feet from the camera and 30 feet then panning between them. Another thing to try out is a solid and still object, like a park bench. Leave it run for 5 minutes and see if it gets bored and hunts. That's the biggie.
 
Hi Nate

I seldom had an issue with a moving camera..it seems to keep up without any issues..where the big issue arose was a fixed camera (handheld or tripod) on two object apart ...that's when the AF got bored and hunted!! Also at full wide the relatively large DOF may not show up any problems so you do need to zoom in a bit. Panning across two people should be near perfect but place two people at different positions and stay like that for a few minutes and the AF struggles!!! The other big issue was when I had two objects in line with each other (say someone at 15' and some one at 30' ) ..the AF will lock into the front person fairly well but if they move away the AF gets "lost"

Hope the A upgrade has a big improvement for everyone!!

Chris
 
Chris, how about I can get two actors to sit for 15 mins, one at 15' and one at 30' in a straight line in front of the camera and we then get the near actor to exit with his/her chair and see what that yields.

I will make sure the two actors are in a straight line and I will not engage face framing.

The range of outcomes appear to be 1) no focus, 2) focus shift to the 2nd actor 3) focus shift to the trees in the distant background.

The test could be repeated with the first actor 15' in line with the camera and the 2nd at 30', say 3 feet to the left or right without face framing.

Then a repeat of the 2nd test with face framing set to ON.
 
Hey Walter

I had issues with wedding speeches mainly where the cam accurately focused on the guy at the lectern but totally lost the plot when he moved out of shot..the worrying part was when he came back into shot the whole screen was a blur and stayed that way.
Get maybe your first person to walk out the shot and see what happens and then see if the AF can correct itself if the same person walks into the shot...Your camera does need to be about 20' away and zoomed up about 4 X at least. I did solve the issue by simply using manual in the end!!
The hunt and "bored" issue seems to take a LOT longer ..typically around maybe 10 minutes when AF will switch focus from a couple outdoors almost filling the frame but instead changes focus to trees in the background...that too is cureable with MF but it would be nice if the hunting part of AF has been cured.. I cannot comment at all on face detection..I was advised to turn it off which I did as more often that not my weddings are shooting a side view so it didn't seem to be that reliable.

I really cannot remember ANY AF issues when the camera was moving and panning at all when it was fully wide ..it only seems to happen when you zoomed up a bit!!

It will be interesting to see your results ..however even on my other cams I still stick to manual focus when the camera is static.

Chris
 
kwkeirstead said:
Here are test results done by CvX Productions on auto-focus capabilities at the AC 160a.
http://youtu.be/5r_QPIA4tsY
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This test seems better than what the original camera could do. I feel like the original would "breathe" a bit before locking onto the subject. I'm going to do this same sort of test this afternoon and see what happens.

I'll also see if I can get the camera to drop focus when on a stationary object.

There's still a good chance we're imagining things though...
 
Here's the video I just made with the original AC160. It's really some high-quality stuff...but I think it will do for our purposes. The point is, we know what it struggles with, and therefore can pretty much make the camera do this on command.

The big one, as Chris mentions, is the camera hunting for focus briefly after sitting on the bushes for a while – when it gets bored. The second biggest one in my opinion is the "jitters" when on the sign post and trees. Faster lock-on or not, it will be interesting to know if the upgraded 160A still has these two particular bad habits.

http://www.youtube.com/watch?v=PhJN_KhZ5gI
 
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I wanted to say thanks to everyone for their efforts in this testing and discussion. There are many people besides myself very interested in this, and watching eagerly.
 
I'm taking my AC160 in today for the upgrade....already downloaded the 1080/60p capability, but really want the AF mods. Taking it to the Hollywood Calif. center about 30 minutes from here.
 
sewolla said:
I'm taking my AC160 in today for the upgrade....already downloaded the 1080/60p capability, but really want the AF mods. Taking it to the Hollywood Calif. center about 30 minutes from here.
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You should run a test or two and record it BEFORE you bring it in that causes what you would consider an auto focus issue and then repeat the same test AFTER you get it back!
 
Nate Haustein said:
Here's the video I just made with the original AC160. It's really some high-quality stuff...but I think it will do for our purposes. The point is, we know what it struggles with, and therefore can pretty much make the camera do this on command.

The big one, as Chris mentions, is the camera hunting for focus briefly after sitting on the bushes for a while – when it gets bored. The second biggest one in my opinion is the "jitters" when on the sign post and trees. Faster lock-on or not, it will be interesting to know if the upgraded 160A still has these two particular bad habits.

http://www.youtube.com/watch?v=PhJN_KhZ5gI
Click to expand...

Thanks for doing that. Truthfully I'm not totally sure that those tests had many issues that my HMC150's wouldn't have too. The getting "bored" thing that I hear people talking about seems to be a huge deal, and yes their was hunting involved in some of those but again, I'm thinking how my AF on my CCD HMC150 works and it might need the occasional "help" in AF. Although it never gets "bored" like people have mentioned the AC160 gets. Interesting though. Thanks for doing that.

BTW, When you start backing up at the end of the video, is it wrong that I totally imagined a car swiping you out of frame. Sorry. ;)
 
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Thanks for that...They both, to me, seem to handle everything pretty normally. Not sure that either one showed anything crazy unusual that my HMC's wouldn't do too. Hmmm.
 
In fact, to me, the 160 seemed to do a better job than the A version but it certainly seems like only turbo focus and assist were attended to in the upgrade. The thing that always worried me (and you can see it in both clips) when you zoom up the camera loses focus everytime but seems to grab it very quickly if you do a quick zoom out. The fact that you get that little fuzzy section even if you do a tiny zoom/pan was annoying to me..it meant that if I wanted to zoom into the couple at weddings during the vows I would get a fraction of a second when it went fuzzy...it seems to be the same sort of "fuzz" I get shooting video on the GH1 and press the shutter button to focus during video.

The 160 and 160A certainly have no problem attaining focus ..it just seems to take a little longer..use it in manual and you have a perfect shot!! Whenever I had my cams on tripod it was in full manual to avoid the fuzzy bits ...then again I see DSLR footage where it's full of focus adjustments which are then cut out in post.

It would still be nice to see if the focus gets bored on a tripod!!! Both my 130's used to do that. I still have no idea why the 130/160 has an AF issue...I shot a wedding on my HMC82's today and I can run them in full auto and go from wide right up to a closeup of the bride signing documents without any issue...it must be the bigger chips???.... Something that might shed some light I discovered today was with mu current cams I can go wide or zoom on a group, handheld, and the zoom display in the LCD might change a few digits up and down but normally stays very constant..on the 130's I remember noticing that the zoom numbers would constantly run over a large value and if changed to feet I could be say 10' from a group of people in full auto and the range would constantly change from anything from 3' right up to infinity and then up and down constantly....maybe see if the A upgrade has made this a bit better???

Chris
 
This is a repeat of an auto-focus test by CVx Productions on an upgraded Panasonic AC-160A.

http://youtu.be/Vi7Pcyw3NlE

In the repeat test, our subject sat in a chair for 10 minutes about 30 feet in front of the camera, then promptly exited from the scene. The focus quickly shifted to background trees 80 feet from the camera.

Some 20 seconds later the subject re-entered the scene to the original position. The focus reverted to the starting focus.

The objective of this test was to comment on various reports on the Panasonic 160 to the effect 1) that the camera focus would "wander'after a time and lose its focus and 2) that when a subject rejoined the scene, the camera would not lock on to the subject.

We found no evidence of these issues in our testing of our upgraded AC160 to AC160A . Clearly it would have been nice to have had an AC160 to parallel record the test.

To view our findings, put the display at 1980 and full screen and use a magnifying glass to view a background leaf just before and after the subject leaves the scene some 10 seconds into the video.

Are you able to see the serrated edges of the leaf after the subject leaves?

Then, about 40 seconds into the video when the subject comes back to the original position, are you able to see the leaf go out of focus again?

If you want to do a test of your own on Auto-Focus (AC160 or AC160A, make sure your foreground and background have reasonable contrast, otherwise you will find that the camera will take time to settle down or may never settle down). It you set auto-IRIS, the lighting level displayed, the iris level and the focus probably will never settle down if the wind is blowing (as was the case in our testing).

Part II of evaluating the AC160 to AC160A upgrade had an objective of testing an upgrade of PUSH AUTO - the only observation we can make after considerable experimentation is that lock-in is instantaneous.

A possible design suggestion would be build up the Push Auto button - having it flush with the camera surface makes it a bit dificult to press. Our field remedy for this will be to superimpose a small piece of black plastic onto the PUSH AUTO button.

If you decide to do this, you are, of course, on your own.

CVx Productions has no affiliation wtih Panasonic other than that of a highly satisfied customer..
 
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Hey Walter

That test went well but I think you mis-understood me just a little bit...my issue was in lower light and indoors when the cam refused to pickup the focus when my speaker returned to the lectern. During my outdoor weddings the issue seemed to be just the AF getting bored ...It focussed perfect on the couple and even though they occupied a good 75% of the frame, 10 minutes into the shoot it decided to focus on the trees in the background. Any static camera and fairly static subject matter is very simple to rectify by using manual focus...in fact the turbo sounds really good so you can nail it instantly!! As you tend to do fixed cam fixed subjects ..like all your choral groups I doubt whether you will ever have an issue as you should be in manual anyway!!

Sounds like the upgrade is certainly well worth doing!!!

Chris
 
Chris,


Thanks for your comments, I will try to replicate the indoor scenario.

Curious why I was unable to repeat your outdoor scenario - I had a subject sit for 10 minutes, the camera did not get "bored".
What I have found to work for choral groups is they usually have three rows of singers on risers and I simply put the focus on the middle row. At a usual distance of 75 feet, there seeems to be no need to change the focus when you are panning (the singers like to see themselves individually so I zoom in once in a while and go row by row).

I am starting do to theatre productions where you can sometimes have 20 people singing/dancing all over the stage. This makes for a very busy videographer.

I find all of these scenarios require different approaches to get good results.

I agree with you re manual focus.

Sometimes an event needs two focus positions. I can set both in advance using focus assist, no problem but then during the event I have to remember two distances and manually re-set from one to the other.

Surely there must exist a gadget that lets you dial in two or more focus positions and "switch" from one to the other. My Manfrotto focus / iris tripod accessory does not let me do this - and 1/2 of a degree manual adjustment can see you go from 5 feet to 50 feet (too sensitive in my opinion). Is there a solution?
 
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