Having read so much about the annoying focus pulsing in this board i wonder: is this a legit error which canon can repair or even send me a new cam (as some of you have stated in the forums) or do i have to deal with it?

It's so unbelievably bad, when i zoom in on a still object it cannot hold focus for even a second :(

thanks
-daniel

I'm guessing this is when using an auto-focus, correct? This is a problem with many auto-focus cameras. The camera is not a human and doesn't always know exactly what you wish to focus on. Sometimes, the camera will get confused between two objects in the frame - especially at long focal lengths.

The sure-fire way to avoid this is to simply focus manually. It may take a little while to get comfortable with, but it is a great skill to get to know and is worth it in the long run.

Manual is defintely the way to go. It's one of the great features of prosumer cameras... use it! :)

Auto is always jerky and could ruin a shot.

hm ok, it maybe just me but neither my fx1, my old cheap 299 bucks canon dv or my sony hdr-hc1e has such problems. i often film interviews with the talents moving forwards and backwards on their chairs while i'm doing the interviews - so there's no way to focus manually for me, neither it seems feasible to control every bit of focus movement on every shot.

i sat on my couch yesterday, connected the A1 to my TV and positioned it about 1,5-2 meters away from me and did a closeup as we have it in mos interviews. it constantly moved back and forth, sometimes even went completely out of focus. light was quite ok.

:(

so... send the A1 back and go for a second FX1 !?

so... send the A1 back and go for a second FX1 !?Yes. If you have an FX1 already, I'm not sure why you would choose a different make and model as a second camera. It's to your advantage to stiick with one brand -- in your case, Sony -- in order to insure compatibility between cameras for batteries, accessories, and most importantly the look of the video.

In my opinion you should definitely switch to a second FX1 or a Z1.

Yes. If you have an FX1 already, I'm not sure why you would choose a different make and model as a second camera. It's to your advantage to stiick with one brand -- in your case, Sony -- in order to insure compatibility between cameras for batteries, accessories, and most importantly the look of the video.

In my opinion you should definitely switch to a second FX1 or a Z1.

my original plan was to sell the fx1 and go for a second A1 as it is superior in terms of runtime with batteries, nightshots and, most of all, has the xlr inputs which are manditory for me right now :(

i've uploaded a sample clip of my problem. hope this helps!

http://www.dreffects.de/tmp/fokusproblem01.wmv

I was blown away by how bad the autofocus was too when I first got my cam. My old 3ccd consumer DV cam is way better. But then I was told that AF and HD doesn't work that well together, so I'm under the impression that that's the main issue.
I haven't tried shooting in DV with my XHA1 yet though, but if the AF is just as bad there, I'd never ever buy anything Canon again. Manual focusing works fine though, and is one of the reasons I needed a better camera anyway. And AF works good for a lot of shots, just have to learn what kind of situations it can't handle at all, and stay away from those, at least that's what I do.

hm what kind of situations would be bad? i somehow consider the clip with me sitting on a chouch pretty common and not at all difficult. what will happen when we start shooting with a steadycam which relies on autofocus on events with bad lightning?

No idea! hehe that's the fun part I guess... Some shots, especially somewhat caotiv ones, where focus shifts dramatically when someone approches the camera etc, with suboptimal lighting, has caused too much problems for me to trust AF for that. Other than that: try and see i guess, that's what I do, and for most shots where I'm not shooting scenery etc, or I am in control and able to keep up with the focusing, I do manual. And that seems to work for me, Auto for the things it can handle and manual for the rest.

Sorry for not being able to be more specific here, I just got the camera a couple weeks ago, so I'm still trying to figure this out myself. :)

It's so unbelievably bad, when i zoom in on a still object it cannot hold focus for even a second :(

I just got my A1, and my first impressions so far was that it was not nearly as good as my GL2 I upgraded from. I was suprised as well, even during bright daylight that it had problems focusing on subjects. I don't mind too much, because I have been wanting to work on my Manual skills more anyways, and this really forces me to do so.. It is good practice especially since I am planning on getting a 35mm adapter here soon, probably brevis.

Luke

thanks for your help. could you advise me on the F setting (sorry don't know the english word for it, german one is 'blende' like F3.2 or something^^)? I know from digital fotography that a F4 Value is barley enough for a portrait photograph. so when shooting interviews it would be good to choose a F value that covers about 30cm in each direction from the focuspoint on so that the talent can move a bit without the manual focus i cannot change when doing the interview myself, loses focus.

thanks for any advice :)

using manual focus and selectively hitting the 'push AF' button has worked great for me. only wish the button was a bit bigger, like on the canon xl lenses.

i'd agree - but i have to be in front of the camera with no operator at hand :(

I shoot with an XL2 and a manual lens, and my 3x which I use the auto focus on occasion.

I looked at your clip and I can say I think the lighting is a problem as well as the focus area. The only SHARP line is the edge of your head and the wall behind you. The lighting on your features is very soft, and the camera is trying to focus between your lips, nose and the sharp lines of your sideburns.

Not what I would consider interview lighting at all, and a challenging frame for autofocus to follow.

If you are not operating the camera, then I would set the subject in place, manually focus on them, and then join them in the scene.

The hazards of wearing too many hats.

Not what I would consider interview lighting at all, and a challenging frame for autofocus to follow.Hm ok, i have tons of interviews lit in similar way, especially on events like E3 or Games Convention which's 'sets' are located on the presentation area of the videogame publisher. There it's being lit to please the human eye. So primarily dark, with red lights etc. I know that sucks compared to a studio environment.

thanks for the explanation on what the focus is trying to do. i just wonder why he can't decide even if i hold absolutely still ;)

My second problem is: when i'm not doing the interviews alone, a steadycam operator is handling the camera (without a focus puller) - do you think the AF will handle the situation better (or less noticeably bad) if there's a constant movement?

The hazards of wearing too many hats.hehe, yep^^

Daniel,

DO you normally shoot only the nose and lower chin of your interview subjects? That's what your clip primarily shows.

Autofocus is looking for sharp deliniations in the subject material. Its looking for contrast. Different manufacturers asign the 'search area' to different parts of the screen. I suspect that canon's 'search area' for focus is primarily center weighted. IN your shots, the center of the screen is all one value... all extreme closeups of your face, with soft lighting... no sharp lines at all. Thus the camera is hunting on something to focus on... your nose? Your lips? Your chin? AND you keep moving. YUP, confusing for the algortithm.

I concur with Chris. This camera is not for you. Sell/return it and stay with the camera that meets your PRIMARY need... good autofocus for your particular shooting style. You'll have to just make do with you secondary needs not being met.

It's always a trade-off.

Daniel,

DO you normally shoot only the nose and lower chin of your interview subjects? That's what your clip primarily shows.

Autofocus is looking for sharp deliniations in the subject material. Its looking for contrast. Different manufacturers asign the 'search area' to different parts of the screen. I suspect that canon's 'search area' for focus is primarily center weighted. IN your shots, the center of the screen is all one value... all extreme closeups of your face, with soft lighting... no sharp lines at all. Thus the camera is hunting on something to focus on... your nose? Your lips? Your chin? AND you keep moving. YUP, confusing for the algortithm.

I concur with Chris. This camera is not for you. Sell/return it and stay with the camera that meets your PRIMARY need... good autofocus for your particular shooting style. You'll have to just make do with you secondary needs not being met.

It's always a trade-off.
thanks for your thoughts! i agree on how confusing the poor AF might have felt seeing only my chin ;) i've first encountered the problem while having the camera sitting on my lap, zooming veeeerrry slowly back from my keyboard / monitor i have in front of my pc.

i think i'll test the camera under real conditions next week and return it if i'm not able to handle it with the AF mode. Do you know any other cameras with similar features (HDV, XLR) for a reasonable price? :)

Ok, i have to adjust my previous statement about AF working for some situations..

After reviewing a lot of footage I have shot today, the focusing when in AF is simply hopeless, and pulsates A LOT, even in a lot of the shots where I thought it would surely do allright.

I guess it's all manual for me when shooting in HD from now.

Anyone tested the difference in AF when shooting in DV/HDV? Is it better in DV?

(And btw, is AF this bad in the consumer HDV/AVCHD etc cameras too?! If so, they're practically worthless..)

they're practically worthless..)my thoughts exactly. the funny thing is: even my 299 bucks thingy does better focus than the A1. Have the FX1 and an HC1E at hand, both do just fine in terms of autofocus.

After reviewing the clip, I must agree completely with the assessment from Richard Alvarez. There are two problems at work, and neither is the fault of the camera. First, not enough light. Auto focus needs to see contrast in order to work, and insufficient light equals insufficient contrast. The second problem is in the second half of the clip... the lens is zoomed in too far for focus to work at such a close distance to the subject. In other words, the distance to the subject is too close for the minimum focusing distance of that particular focal length.

Sorry, clearly an example of operator error here.

1. Add more light.

2. Increase the distance from the camera to the subject, or decrease the focal length (zoom out).

gonna try to film some test footage handheld in bright daylight tomorrow, hopefully with better results :)

despite the obviously poor light - my very cheap two other cams did just fine ;)

Just out of interest. Are you on Normal AF or Instant AF?

I often film under dark circumstances as a weddingvideographer, especially during the party in the evening. I actually use the autofocus of my vx2100 a lot, just because it is so good and switch to manual whenever necessary and then use the "one push" button to fix the focus to a certain object. Only when it gets real dark the autofocus won't manage but for situations as was shown in the example clip I'm sure that my Sony will give a sharp image zoomed in or not.
Also a big difference I noticed is that the autozoom reacted real quick on the A1 which makes it even more noticable, my Sony does the focus adjustments more slower so it looks more natural if it would loose it's focus and restores it.
I was planning to buy an hd cam by the ending of the year or beginning next year and looking at the autofocus capabilities of the canon (It is the XHA1, right?) this will not be a camera for me. Most of you will probably say use the manual controls but having used my vx2100 allmost 3 years it has never let me down on that part and manual focussing on such a sony isn't particilary easy were you have to deal with too many things which can change in an instant. A good "point and shoot" camera should be able to deal with most of these changes without a problem so you only need to switch to manual in a few occasions.
If you are in a controlled situation then it's completely different because you have the time to set everything right, then you should use manual control at most times.

Noa, yes this is the XH A1. I Sort of expected that a 3,5k Camera inherits all the features from a 900 Bucks Cam like the HC1E and improves them (like the AF^^)

The sort of things we do seem to compare a lot. Dark Environment (Party, Church/Event), constantly changing subjects and no time or way to focus manually. I'm heading out to the wilderness in a few minutes and try to shoot in bright daylight (having 100K right now^^) and am trying to get some handheld shots of moving objects and some stills with zoom in/out on objects with high contrasts and stuff. hopefully there's no pulsing :)

gonna post my video here.

one last thing before i go: the focus-speed option in the camera-setup menu only controls the focus preset switches speed, right? so where do i set the AF Focus speed lower?

thanks :)

@Bill
Instant AF - but Normal AF gives me exactly! the same results with my chin :)

hi daniel,

there is no way to set the auto focus speed i'm aware of.

The sort of things we do seem to compare a lot. Dark Environment (Party, Church/Event), constantly changing subjects and no time or way to focus manually.


i don't think this has to be the case. news crews almost never use auto focus, just because of the issue we're talking about here, focus hunting, and shooting breaking news is fairly dynamic. in all fairness, they have true manual lenses with markings on the barrel.

back when the xl1 came out, the servo driven focus ring was a fairly major point of concern, especially for event videographers. there were no markings on the lens barrel, and working in manual focus for dynamic event work was difficult (to put it mildly). it became pretty common practice, and a very workable solution, to put the xl camera's lens into manual mode and hit the 'push AF' button whenever the subject was framed. i've shot dozens of events this way and it's a very comfortable way of shooting for me. even for the zoom-happy, most zooms i find i edit out, but even if i'm shooting a zoom to keep in, i use the tried and true: i zoom in, set focus, zoom out, and zoom in again at the desired zoom speed.

even when shooting on a stabilizer where i can't really touch the camera, i'll try not to use auto focus. i'll usually keep the camera at full wide to keep a large DOF and set the focal length just below infinity (or occassionally use a focus/zoom controller).

on a side note, when i got my xha1 back from factory service recently, i noticed that "I AF" was replaced by "S QUICK AF". it seems to behave exactly the same, so not sure what the story is there.

sounds pretty interesting :) have to try that on a concert or something with fast moving talents. just was outside and shot a few ducks and stuff. :)