Autofocus question

H

Henri77

Member
Very basic query about HVX.
I have the orig dvx100 and wonder: If the HVX autofocus operates any differently than later DVX models, A&B in 24p. Is it quicker, more accurate? As I understand autofocus with dvxB is still nearly useless (too slow)
Accurate manual focus is nearly impossible for me with significant actor ,camera moves (handheld) and a cam that could hold focus (auto mode) would be a vast improvement in24p for such situations. I'm about ready to go to HD, 16x9 chip
and I know the Canon A1 is great in this respect though lacking var frame rate...something I really value.
 
For me "Autofocus" is spelled "Out-of-focus".

Almost all autofocus systems are too easily fooled by prominent, bright objects which are far behind the intended subject.

You're far better off focusing manually and making sure you got it right than finding out in post that it's annoyingly back-focused.

Manual focus with the HVX is not that hard. Just make sure you got the EVF detail turned on, and use the eyepiece rather than the flip-out LCD.
 
i've used the push autofocus a couple of times to double check my focus and that's been pretty good, but i agree w/ the others - autofocus is just too slow (unless you're in 60fps) and every time I try to use it because of some situation where it's just too much for me to focus AND do everything else, autofocus winds up sucking so much that I just figure out how to work manual focus in w/ everything else

but you can push autofocus a couple of times or have it set to 60fps/60i and that would give you the best autofocus setups
 
I don't know guys...

Henri77 does have a point regarding dynamic action that is either difficult to block if not outright unpredictable.

Autofocus has worked for me in a couple of situations. Sometimes I just widen the zoom a little so the AF doesn't go into indecision mode.

That said, I've not been disapointed by the HVX in 24p. I've never shot in 60i where that autofocus demon lives.
 
My understanding is that autofocus is actually more responsive in 60i. Responsiveness decreases in progressive mode and with slower framerates.

Autofocus will always be criticized for making poor decisions, it's not psychic and doesn't know what the shooter wants. When it does change focus from one object to another, should it use a snap focus or something more gradual that's not so jarring?
 
Unless you're using a 35mm adapter, you can take advantage of the big DOF of the 1/3" chip camera. Since you're shooting handheld, you're most certainly (I hope!) shooting at full wide angle, so you have enormous DOF, unless the subjects get really close to the lens. But when they do, then it's easy to judge distance and match the focus. Study the DOF charts for your lens settings--you'll find that you have quite a window of acceptable focus, and as others have stated here, it will look a lot better than relying on autofocus.
 
THoff said:
My understanding is that autofocus is actually more responsive in 60i. Responsiveness decreases in progressive mode and with slower framerates.

Autofocus will always be criticized for making poor decisions, it's not psychic and doesn't know what the shooter wants. When it does change focus from one object to another, should it use a snap focus or something more gradual that's not so jarring?
Click to expand...



Whoops...you are correct on the 60i. I got it backwards. Ironically, I've had only "predictable" AF issues in 24p...Well, at least I should have known better.
 
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to make it more clear for future people checking it out, the reason the autofocus can work better in 60i mode is because the chip is sending 60fps to the camera, which gives the autofocus 60 times per second to determine focus. if you're shooting 24 or 30fps, you've cut the number of frames at least in half, which gives the autofocus far fewer frames on which to determine the point of focus.
 
I ask cause the orig DVX100 doesn't have peaking and accurate man focus can be tough when everything's moving... and one can't use a monitor.
But yeah I need to practice more.....this trailer "fell to Earth" simply knocked me out, totally....shot with the Orig dvx by guys who REALLY know what they're doing....
bloody astonishing work.....

Thing I'll just rent a HVX sometime soon and see what it's like... a dedicated 16X9 cam is my dream.
 
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