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Sony XDCAM EX Pro Handhelds
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Old December 22nd, 2007, 01:03 PM   #31
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Quote:
Originally Posted by Malcolm Hamilton View Post
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
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.
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Old December 22nd, 2007, 01:07 PM   #32
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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.
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Old December 22nd, 2007, 01:09 PM   #33
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Originally Posted by Steven Thomas View Post
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.
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?
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Old December 22nd, 2007, 01:25 PM   #34
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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
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Old December 22nd, 2007, 04:12 PM   #35
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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.
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Old December 22nd, 2007, 04:42 PM   #36
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Originally Posted by Malcolm Hamilton View Post
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
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.
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Old December 22nd, 2007, 05:34 PM   #37
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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 ;)
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Old December 22nd, 2007, 08:46 PM   #38
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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
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Old December 22nd, 2007, 08:57 PM   #39
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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.
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Old December 22nd, 2007, 09:27 PM   #40
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Originally Posted by Bill Heslip View Post
Malcolm, you seem to be a perfect candidate for the Sony wide-angle
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
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Old December 22nd, 2007, 09:53 PM   #41
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I think we need to put this into perspective. The EX1 is probably the most expensive camera with autofocus. Take the next step up and you don't get it at all, I don't think there's even a SD 1/2" camera with it.

Think it through, what do you want the AF to focus on. You can easily get shallow enough DOF where the most visible edge might not be where you want focus anyway, do you want to focus on the talents ears, eyes or nose. The first option will be the easiest for the AF to lock onto, the latter could be a problem and the eyes might be difficult too as it tries to find an edge. My DSC has a centre focus marker which is handy but hardly useful with moving images. Even more of a problem is with 16:9, it's quite common not to have the subject centre frame.

You can solve this to some extent with a rangefinder but without a scope / laser marker how do you know what it's measuring the distance to. Great if you're shooting set pieces, for gun and run largely useless.

I'm dead set hopeless at focussing and I wish there was a magic solution but I bought an EX1 knowing I'd need to hone my skills. I've mostly shot with a PD170 in the past or hired a good cameraman who could do the three ring dance while he danced around the talent.
The good news is if you're shooting exteriors you've probably got enough light so you can iris down and get enough DOF so focussing is less critical, as others have said staying wide will also help. One thing to check regularly is backfocus. The old zoom in, focus, zoom out trick will bring you unstuck if the backfocus is out.
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Old December 22nd, 2007, 10:03 PM   #42
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Bob,
I thought I made it fairly clear that I don't normally use AF.
I'm not trying to make excuses for focusing a camera.

It's ovbvious AF can't read your mind on what you want in focus.

The thread was to understand why the EX1 AF is hunting even though the conditions are optimal. I just would like to know if the problem is across all cameras, or tied to just mine. I layed out a simple test for those who have the camera.

True about back focus. I've been nailed on that several times with my JVC HD100.
Ideally, you need to check it before any shoot and check it during the day, especially if there are temp changes.

Fortunately, no need to worry about back focus on the EX1, although, I hear there is a service menu option for adjustment in the factory or service.
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Old December 22nd, 2007, 10:15 PM   #43
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Not fast. I was working through features last evening and auto focus was one. I'm used to giving the FX1 a jab for quick auto focus but on the EX I thought nothing was happening. So confirm slow and hunting, but not having noticed this thread I didn't quantify. Too slow to grab focus for run & gun but haven't checked how capably it tracks dynamic focus (ie. full auto focus). Peaking looks good for manual focus and so far I seem to be able to focus using the VF.
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Old December 22nd, 2007, 10:27 PM   #44
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Thanks Serena.
When you get a chance, try the test I mentioned in this thread. I'd be interested if it shows the same symptoms.

Yes, the EX1 peaking really works great. The LCD is capable of making decent focus judgements. I was very surprised.
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Old December 22nd, 2007, 11:50 PM   #45
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Quote:
Originally Posted by Malcolm Hamilton View Post
Bill, re the wide-angle - - do you mean a wide-angle lens I add on?
I was referring to the WA lens (add-on) made especially for the EX-1 (VLC-EX0877). There are or will soon be third party WA lenses available, although they will probably not be able to take advantage of the CA (chromatic aberration) reduction capability the Sony combo offers. In practice, no one yet knows how well this works.
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