PMW-EX1 Auto Focus Slow?
 

Please check your camera's AF response time.

Even under good light with good contrast and aiming at objects with vertical line structures, my camera is reponding real slow in AF mode?

Sometimes it may take as long as 6 seconds or more to focus. Sometimes it does not. Also looking at the DOF LCD indicator, it appears to hunt around even though it's locked on the subject.

Any thoughts on this and what you all are seeing?

You would not be able to use this in a run-and-gun situation, well unless you don't mind your shots out of focus. ;)

I believe the DOF LCD indicator could well show varying values when focus is locked as it is governed/determined by the aperature and zoom position, not by the point of focus itself. That's my understanding of this feature as described in the manual. In conditions where iris or FOV(zoom) is varied the DOF will also vary.

I can't comment on AF response though, waiting until January before I make the purchase.

Steven, I could have sworn there is a speed control for autofocus in the menus. I remember seeing that for sure for ATW (auto white balance).

ATW is sompletely different in that you actually might not want it to react to any fast or accidental light tempererate changes; autofocus shhould alwayd perform as quick as possible.

I'll check my camera. It certainly seems faster than the HVX!

Maybe turning on/off MF Assist impacts speed?

It defaults OFF, I can try on. You never know, although this feature is for
using AF to get you closer after you make a manual focus adjustment.

I will try turning it on.

There's no control parameter for AF speed.

Also, even when mine finds focus it continues to hunt.
Once it finds focus, it modulates just slightly in and out.
It happens from wide through various ranges through the zoom travel.

Yes, there's decent light and objects that can grab focus. I even tried it outside in the daylight.
As suggested by Craig, I've tried to see if the MF assist impacts it.
No difference.

You can even display the focus distance/DOF display item and watch
it slightly move around from left to right on the focus distance line.

Very strange.

Has everyone got a chance to determine if their camera has this problem, or am I just "bad luck to a hunting dog?" LOL

Actually, this is no laughing matter....
Also, again the AF is running real slow. Usually takes 3 to 6 seconds, or not at all.

I tested AF at my dealer yesterday. Had about 3 hours hands on with the camera. While it wasn't as fast as my PD170, it seemed ok. It did seem a bit slower when I was zoomed in and moved it to a neighboring object vs wide though.

Thanks Craig.
When you say a bit, are we talking 3 to 6 seconds?

Also, I was real surprised how slow it was even at wide where DOF is huge.

3 seconds seems right when I was zoomed in and moving from one object to a an next to it but further away. It didn't concern me because in those situations I'd using Push Auto when doing "run and gun" and that worked fast (it seemed to me). When I was wide I didn't notice the issue.

The only time I resort to auto is when I'm tracking an object with changing focus so Push Auto would be awkward. That's a bit different than changing the "point of interest" from one object to another.

Actually a good test would have been someone walking towards me/the camera but I didn't try that.

To test auto having two people standing at different focal points might have worked (moving from near face to far face for example).

Hmmm.
Maybe mine's the same.
Does yours hunt.

You will probably need a monitor hooked up to see it.

Also, if you turn on the focus/dof display item (Lens Info), you can actually see the focus point wandering around on the line.

You can turn this on by first setting your camera to manual AF operation, then push the USER 1 button. By hitting that but again it changes from meters to feet. This is aasuming you have not reconfigured the switch fro the "Len Info" setting. Now switch back to AF mode and check it.

I got my first hands-on look at the EX1 tonight, and both myself and a friend felt the AF response was unsatisfactory. Bummer. :-(

Once it locked focus, did you look to see it there was still a small amount of "hunting"?

Mine finds focus, then slightly moves back and forth trying to readjust.
This happens even under good light and objects with good contrast.

You have to look for it using a decent monitor, but you can visually see it "breathing" in and out of focus.

That's why I mention the MF assist. It will try to "walk the focus in" and I can imagine in many circumstances that's not a good thing. Whenever you see it hunting, see if changing MF Assist impacts it.

This is all pretty typical with 24 progrssive on all the cameras isn't it. Not very good on the HVX either- lots of hunting.

Any more on this?

There's times my camera will not even lock onto focus at all.
No, I'm not shooting a bare wall ;), this is aiming right at well lit high
contrast objects.

Auto focus is indeed slow on the PVW-EX1 and I have no intend to use it as the manual focus ring is probably one of the primary reason I liked the EX. It works well but it takes a lot of turning to go form closeup to infinity and it is not quite as smooth as a 15K HD lens. That said, people who have struggled manual focusing on the Z1 or HVX-200 will be very pleased.

I feel there is something inerant to motion pictures acquisition that will never allow autofocus systems to work well. Take for exemple a "rack focus", there is no way a computer chip will ever figure this one out.

Thierry.

And I forgot to mention the iris ring, even better than the focus one. Smooth, no stair stepping, very fine control of your exposure. Again, as for focusing, I rarely use auto iris.

Thierry.

Perhaps - but maybe that's just because having a computer drive an electric motor which moves a complex mechanical lens system to try and focus an image that the computer can't see or understand is the wrong approach. A better approach would be to not have to worry about focusing at all while we're shooting - let the computer deal with focus in post so that we can keyframe things like racks or track moving subjects.


It sounds a little 'sci-fi'... until you've seen this: http://graphics.stanford.edu/papers/lfcamera/
(make sure you watch the video: http://graphics.stanford.edu/papers/...a/lfcamera.avi)

Now that your mind is suitably blown, back to the EX. I suspect the slow autofocus is simply the price we have to pay for having a true mechanical lens - it's got to be much easier to make a fast, smooth and quiet autofocus when you don't have to have the lens elements coupled to gears meant to be turned by a large outer ring.

For me, this news about the slow auto-focus is certainly bad news. I might get no sympathy from most of you on this forum - - you're talented camera operators who love (and deserve) the manual zoom, manual iris, etc.. But I'm just coming to camera work (from producing, directing and editing), and I've been using autofocus almost exclusively (with the Sony Z1U) for the last five months. So, why don't I get stick with the Z1U, or get another camera like it, with a cheaper lens (that can autofocus)? Maybe I should. But I really wanted to get away from tape-based shooting, and I like the fact that the EX1 can shoot in lower light levels (requiring less lighting, another area I feel inadequate in).
Any advice? Is the autofocus on the EX1 so bad as to make it essentially UNUSEABLE?
Let me add this about how I shoot, in case I could get by with manual focus (and just don't know it) - - for most of the shooting I do, I seldom zoom... I usually stay zoomed out (if I want a tighter shot, I move closer). Would this simplify things for me, re focusing?
If people here advise me to NOT get the EX1, is there another camera you would suggest (flash-card based; able to shoot in low light, etc.)
Thanks,
Malcolm

Malcolm, btw I'd been editing nearly 20 years before I started shooting so I do know where you're coming from.

When using my PD-170 I relied on Push Auto since trying to deal with that servo controlled ring was a pain. Having "full manual" control is a blessing. I can focus fast since the ring allows me to.

That said, there is a variety of different "auto focus" situations so the camera response may not be "equal" in all those situations.

It may be one thing to move from one object to another in different focal planes. That might be slow for this camera to respond.

It's another to track a single subject changing the focal plane.

In other words, tracking a single moving object may be different than switching objects, so I'd test those two circumstances separately.

There's also lighting/contrast as a factor and the speed at which it change may be affected by that too.

Think about how the auto focus works and discerns the subject.

So the tests (that I can think of)
high contrast tracking a subject
low contrast tracking a subject
high contrast changing a subject
low contrast changing a subject
one might also try auto always on vs manual with push auto.

This EX1 autofocus news is BAD

Focus is my #1 issue in HD

Coming from big cameras with real (& expensive) viewfinders with which we have a hard enough time "estimating" focus... the small cameras with really inferior monitoring and often using them at arms length from our eyes and usually not in the best lightning conditions... well, autofocus that works is a great (necessary) tool!

A 2" viewfinder on the big cameras just can't cut it for HD focus. Heck in Sd the producer would look at the 8" CRT and say "it's soft". Now in HD we need a 17" or 24" display to even estimate what it will look like on a 42" or larger panel to the viewers at home

For us, the small cameras are a different tool than the big cameras - with the small format you can shoot in styles that the big cameras can't, they are just too big. But, autofocus is critical in these fast, documentary style, handheld situations

The HVX200 autofocus was/is a joke. The Canon A1/G1 autofocus works incredibly well! To think we'll take a huge step backwards in autofocus with the EX1 is not good news!

thanks, Craig, for your reply.
I can't test the camera out, as I don't have one (I was on the verge of buying one, when I saw this thread)... but I hope others, who do have the camera, continue to weigh in on this.
I'm concerned because of what Steven Thomas, says, i.e. - -
”There's times my camera will not even lock onto focus at all”

... to me, that means the autofocus is unuseable!

But then, Leonard Levy says:
“This is all pretty typical with 24 progrssive on all the cameras isn't it. Not very good on the HVX either- lots of hunting”

... does this mean that if I shoot 30 fps, autofocus might work better?
Thanks,
Malcolm

Jon, you apparently haven't used the LCD with with the EX1. It's beyond anything I've seen in detail on a camera LCD. With both Expand Focus and Peaking as a choice (and while in record too) I can nail focus pretty fast in full manual.

Just for reference here...

What other "professional" lens has Auto Focus anyways? This is a real Fujinon Lens for the most part and there are going to be some drawbacks when trying to integrate consumer or prosumer grade features into a camera of this caliber. Personally, I would have rather they left off the AF completely, because when dealing with other professional cameras, its not typically going to be an option. I understand that the EX1 was made in the smaller form factor, but for people used to a professional camera and lens, AF being a bit slow is not a big problem. It will probably only create issues for people stepping up from lower end cameras.

My thoughts exactly, I have rarely, if ever, used AF on the DVX100 I bought years ago I am so used to all manual lenses. This is by no means a deal breaker for me. But, does the EX1 have a push auto function? I have used that a few times and found it handy when my eyes get screwed up from wind or salt water.

I have an A1 and I've never tried the autofocus. However, I don't use an external monitor and I've never had trouble focusing on the LCD with peaking turned on - and from everything I've read here the LCD on the EX is far better, as is peaking, than on the A1. I can't imagine it's going to be difficult to focus. In either case, I'd rather have a whole shot look a little soft than risk have the autofocus hunting in the middle of a shot.

I hear what you're saying, Kit (and other contributors, like Evan, seem to agree that for pro users, poor autofocus isn't going to be a problem). If you don't mind, though, now I'm wondering how tricky it might be for me to get the hang of manual focus, and I'd love any advice. As I say, I'm a bit new to shooting - - I realize this perhaps means I should stick with the Z1, but I'd like to upgrade for the reasons I gave before (mostly: sick of tapes & want to get into editing faster; also, want to do less lighting).

I'd love know how hard it would be for me to learn to focus manually... I'd hate to start messing things up by shooting soft... Is the EX1 display so good (people are raving about it) that this is unlikely?
And here's my other question again (sorry if it sounds a bit silly) - - the fact that I mostly shoot with the lens zoomed out completely (if I want a tighter shot, I move closer) - - would this make it easier for me to stay in focus, in manual? (I realize that if I want to shoot someone walking towards the camera from 50 feet away, I'd have to be changing focus as they approach and pass me; but if I'm walking along beside them, if I stay zoomed out, I shouldn't have to adjust the focus, right?)
Thanks for your patience,
Malcolm

I've been waiting for more info regarding the AF, hence this thread.

This question stems from the possibilty that there is something wrong with my camera. Now, I'm starting to wonder if this is across all EX1 cameras. From using other cameras, I know that AF can be questionable most of the time. Due to the nature of AF sampling, you need to use a higher frame / shutter rate. Using interlace, since two fields roll by per given frame, it tends to work the best. Therefore, ideally 720 60P or 1080 60i should be selected.

Having said that, here's what i've found with the PMW-EX1. Even if the camera is stationary and aimed at good high contrast structures, it will not lock and rest. It breathes (pulses) in and out at a steady rate.

I'm not sure how Sony has setup the AF matrix, 5 point, center weighted, full field matrix, etc, but it's apparent that it needs to be tweaked. I would believe firmware could accomodate this problem. Once it locks on its strongest peaking, it needs to stop servo. It could be their AF servo window is small. Once the camera sees it highest peak, they probably need to open the limits up just a bit.

To test for what I'm seeing.

1. Set you camera on a tripod under adequate light.
2. Set the camera to 1080 HQ 60i (1/125) or 720 60P (1/125)
3. Slide the lens to AF/MF away from body.
4. Slide AF switch on side if lens to "Auto" position. (Full AF is now on)
5. Turn menu option "MF Assist" OFF.
6. Turn ON "display info" to show DOF LCD display.
7. Turn ON "Peaking" and set its menu Level setting to "high".
The last two steps will aid in watching the AF problem.
8. Set the camera/tripod about 10' from your zoom in a bit and allow the camera to focus on your high contrast objects.

In my case, you can watch it pulse in and out of focus for about 8 seconds or longer. NOW, if you turn ON the "MF ASSIST" menu option and readjust to make the AF system work again, It will pulse almost continually and never stop.

If you shut off the the AF switch to "MANU" manual position, this allows the camera to be in manual / AF with the option to press the bottom AF push button for auto focus assist. Now, using this switch it starts to auto focus continually pulsing in and out just like the full auto focus mode.

Please try the above test.

Even using the camera under normal wide conditions when your doing run-and-gun, even with the wide DOF you can watch the focus breathe. Using the LCD DOF lens info feature, you can waych that bounce around while the AF pulses.

I know AF has never been that great on a lot of cameras, I know, I've used them. My concern is with the continuous pulsing issue.

I known a lot of users, including myself never use AF. But, this should at least work to some degree. I understand hunting when there's moving images, but when capturing with the camera not moving shooting stationary objects with good light and good contrast, this should "lock" servo, not pulse.

Generally the wider the lens the less critical the focus, so yes, in your example it's not likely you'd have to change the focus. Zoom all the way into your subject, focus using peaking (and magnification if necessary) then zoom out and you should be absolutely sharp.

In situations where things are moving around outside of your control it becomes about getting good at estimating distance and knowing what your depth of field is - in fact your method of staying wide and moving the camera closer is the best practice because it gives you more room. Find the distances at which the wide angle gives you a good close up, medium, and long shot and learn to eyeball those distances so you can keep the camera in focus by moving it rather than by changing the focus.

Doesn't the EX have a push-button 'focus cleanup' type mode where you get it close manually and then hitting the button refines it using the autofocus system? Has anyone tried this, and if so is it any good? That seems like it might give you the best of both worlds because it lets you tell the camera approximately where to focus and it thenhas a much smaller range to seek within - assuming it's a momentary thing you can trigger and not a full time mode which can hunt when you don't want it too.

Progressive is hard for auto focus systems generally. The DVX or HVX are fine at 60i but very slow and continually hunting at 24P. The Z1 never had true 24P that's probably why it was faster.
I don't know whether 30P would be better but it might since it samples more often.

You're absolutely right, that does sound like an error of some sort. Does the EX have an external focus assist sensor like the A1? If so, where is it located and is it possible something is obscuring it or it's dirty?

Evan, thank you so much for this advice. It sounds do-able for me; I'll weigh and balance the benefits and challenges of the EX1 (at least I now know I could probably learn to focus manually), vs., I guess, the Canon XH A1, that boasts about its Instant Autofocus.
I do appreciate the help,
Malcolm

Honestly, the only auto focus I have ever used is the XL1 and it too teneded to refocus even on a static shot (borrowed one from a buddy for a 3rd camera). It was annoying as hell trying to edit. Manual focus in my book is the only way to go. As someone mentioned earlier, zoom all the way in, focus, and anything in that plane is going to be in focus no matter how far you zoom out. Wide shots are definitely more forgiving, but overall, manual focus is pretty simple. It will take you all of 10 minutes to learn, another little bit to master and you'll never look back. All you hae to do is turn the focus wheel until your subject is sharp. They say that HD is much harder to focus than SD, but most of these new cameras have some sort of focus assist, where the edges will glow when things are in focus. Point is, you'll start using manual focus and wonder why you never used it in the first place. Soory to hear that the AF is on the fritz, but in a pro camera, you should never need it, and the EX1 IS a pro camera.

Malcolm, you seem to be a perfect candidate for the Sony wide-angle. Fewer critical focus issues (in the SD world anyway, can't vouch for HD, yet). Focus in manual and leave it, for the most part.

And I agree with fellow manual focus fans. Once you get the hang of it, you'll never go back.

Has anyone been able to confirm what I'm seeing with my camera?
I posted a simple test in my previous post. This way it will match what I'm seeing (if it does have the issue) one for one.

Like I said in my post. I don't normally use AF, but in the out of ordinary event I do, it would be nice if it at least some what worked.

I know it's a pro camera. That's why I bought it ;)

Auto Focus test
 

Hi Steven. I am a new to posting here but I have been following the forum for quite some time. I just set up and did the auto focus test as you suggested and I am getting similar results.

The focus gets close in 2-3 seconds but never truly locks in. I can see it both on the meter and on my monitor.

Coming from a DV background and always shooting run and gun style of action sports this concerns me as well. I welcome the ability to finally have a lens with true manual controls but in many situations a decent AF helps.

I waited a long time to upgrade from DV and I am hoping that this may be remedied through firmware. I also have to send my EX1 in for the vignette issue.

I am trying to keep my faith that I made a wise decision adopting early with the EX1.

Thanks
Dasher

Thanks Charles.
Yes, mine does get close, but just slightly pulses in and out of foccus.
It's odd because looking at the peaking I can see where it should stay locked and disable its servo, but if just keep moving back and forth.

Yes, apparently, this is what being an early adopter is all about.
I'm surprised these things were not noticed with the pre-production cam testers.

Again, I have used a lot of cameras and AF has only been just OK, some are very slow and fussy.
In this case, it doesn't really work. If nothing is moving, camera or image, it should be able to lock on good well lit high contrast objects.

Bill, I appreciate the encouragement... re the wide-angle - - do you mean a wide-angle lens I add on? If so, have contributors to this forum settled on a good one? (last time I checked, people were still wondering about thread-diameter issues).
Cheers,
Malcolm