Focusing

The "Push Auto" focus button is a great, and under-rated and under-used, feature of the DVX-HVX line. I use it all the time, always with a full zoom and wide apeture. That along with "peaking" allows for excellent focusing capabilities.


One thing that Barry didn't mention is changing the viewfinder to b/w. This allows for finer viewing and focusing without un-needed chroma information.
 
Barry, have you really noticed that footage above 6.8 is softer or is that more theoretical?

Also How do you feel about the auto-focus on the HVX. Sometimes on run and gun its is far easier to use than push button or manual .
I get freaked out when I see those footage numbers bouncing around in the viewfinder, but the footage usually seems to be OK.
 
F/11 gets alarmingly soft. F/9.6 looks basically reasonable, but I worry that the reds might be defocusing. So I say stick with f/8 or above.

As for autofocus, I never use it unless it's a crazy red-carpet event or something and I'm having to hold the camera overhead; the other time I use it is to set backfocus on the Letus35. Autofocus is nearly useless in 24p mode, but in 60i/60p it performs reasonably well.
 
Barry -

Can you discuss Infinity Focus a bit? The range of focus-ring motion for which the distance measure is "infinity" is a significant portion of it's travel, and I find that nothing ever seems to be in focus at the extreme end... even, say, the moon, which of course is not infinitely distant but, pretty close. Generally, it seems to me that 164 feet (the maximum) works well for an "infinite" focus, while infinite focus works for very little, or nothing. I'm tempted to try and make a hard stop around 164'...

I've been shootin' birds for a project, and it's tough! Even at reasonable distances, they tend not to be visible at all in the viewfinder; and of course they move around pretty fast when one's aiming for fairly close shots of them in flight. This is done handheld (or shoulder-braced)... and the birds I'm shooting are pretty rare. Any tips on how to handle focus in this situation would be appreciated!

P.S., for those interested... I tried using the Varizoom PZFI with the shoulder brace for this... but it proved pretty useless. It's just too jittery, and requires too fine a touch... it seems to jump directly from 30' to infinity when you breathe on it.... it works OK for close subjects, having a lot of travel in the 0-10' range, but is too sensitive after that. My problem with the infinite focus is that it would be nice to be able to easily shift into such a focus when the birds reach a certain distance, but infinity never works - 164' does, but is real hard to pin down...
 
The infinity setting is a tad tricky, because just like on the DVX, there's "infinity" and then there's room to move past infinity. The HVX works the same way -- if you put it in "NUMBER" mode instead of "ft/meters" mode, you'll see that the "push-to-infinity" setting goes to MF95, and you can still keep turning the ring up to MF99. When in ft/meters mode you don't see that change; anything from MF95 on up is always listed as "infinity" so you may not even know that you're "past infinity".

My solution for that has always been to just press the push-to-infinity button to force it to what should be true infinity. The only way to really calibrate that would be to focus on something that is actually "infinity" away; the moon would be a perfect thing to use, or mountains on the horizon.

When focus is crucial, I always like to have my f-stop down a couple of stops; if your lighting conditions allow, go for f/4 or f/5.6. At f/5.6 (and focusing at 164') your depth of field should extend from 80' all the way to infinity, with the lens set at full telephoto.
 
Yeah - I keep the f-stop small (usually around f/5.6 - f/9.8), and have indeed settled on 164' as the generally useful setting... but of course my money shot involves the birdy swooping in close, much closer than the 80'... and I guess the best way to deal with that is practice, practice, practice (which I'm doing a lot of). I guess it may be better to skip the shoulder mount and find a hand position that lets me get to the infinite focus button easily... but patiently sitting there for hours waiting for the bird, getting in frame, zooming in, focusing, all while maintaining a fairly steady image - it's tough! Practice, practice...
 
The distance reading on the HVX is inadequate when it comes to infinity focus. That's why I change to display to numbers (ie MF) when I know I need to focus on distant objects.

Here's my reasoning. On my camera, the MF93 reading is equivalent to focus from 147' to infinity on the distance setting. (Just switch the display setting back and forth and you'll see). Yet the focus of the lens is still changing from MF93 to MF99. If you had the distance displayed, all you'll see is infinity in that range and your focus can be way off. (Yes, I found out the hard way).

Setting your focus to 164' is the same as setting it to MF93. Yet the push infinity button sets it to MF95. What I end up doing is a manual focus (or prefocus) on the subject if possible. If that's not possible, then I vary the focus between MF93 and MF96 (guestimate) and set a small aperture. If you had your display set to show the distance, you would NOT be able to do this. All you'll see on the display when you turn the focus ring is infinity, when in fact your focus is changing.
 
I don't have the HVX yet, but i was wondering is focusing in DVCpro50 an issue? I am planning to do a project in SD DVCPro50, once i get the camera.
 
The same question that a few people have asked in this thread is still yet to be answered...

"Is there a mark equivalent to the "film plane", or does Panasonic consider the measurement from the front of the glass?"

Just wanted to confirm, but I think it's the front of the glass. I guess we are looking for a precise measuring point...
 
Thanks alot Barry, Now the camera assistants that always bug me about this question can now sleep at night.

Cheers,

Nathan
 
Newbie question- BUT its seems when I put the camera into maual focus it still says AF in the viewfinder and acts as if its AF WHY is this ? Camera error? OR operator error??helpp?
 
Just one thing, regardless if we are using the front of the lens... the number displayed on the EVF is wrong on HVX200.

I tried and tested with a sharp charter with almost all "lens" and iris stops... and the measure tape and autofocus measures are always complete diferent...

And those increase with the distance (those are not always the same numbers, can be 30cm up to 3m).

Also, I tried to do the inverse strategy I put on manual and did turn the ring with the tape measure values. And the image became complete unfocus.

Have anyone tried this? It´s really a such big problem and the Panasonic don´t give any info about external focus pulling measurement on the manual...
 
I have said before that the in camera measurement is only approximate and shuold not be used for critical focusing
 
I haven't thoroughly tested for focus mark congruence on my HVX's, but I never noticed them being terribly off. I generally use a tape measure when available and appropriate to get a rough idea, but I rely on the focus assist feaures of the HVX to give me proper focus. When the HVX tells me it is in focus, that is what I go off of. So, I never gave too much attention as to how accurate the distance read outs are, but they seemed accurate to me. Accurate enough to guess a distance, put the HVX focus at that distance, and then use focus assist, and evf detail to fine tune.

Perhaps I will test mine out if I get the time

Later,
Jason
 
Re. focussing for infinity, esp. for landscapes: does anyone here use the hyperfocal concept with these cameras? This is something I use in the stills world almost daily.

Basic concept is that depth of field varies with aperture; when wide open this slice of the image (where the circle of confusion is small enough that the image looks perfectly sharp) is relatively shallow; when the iris is stopped down, the slice becomes thicker.

The hyperfocal distance is when you set the distance on the lens to the *front* edge of this slice; the rear edge by definition will be at infinity. If you use the hyperfocal distance, rather than setting the lens to infinity, then the maximum DOF will be experienced: this will give you the greatest front-to-back sharpness that is possible at any aperture.

With the small sensors of modern video cameras (compared to full frame 35mm equivalent sensors) the DOF is inherently much deeper anyway, but this concept might be handy for the landscape shooter. hth, kl
 
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