Funky focus when zoomed at DVinfo.net

Gene Crucean · April 23rd, 2007, 06:45 AM

Does anyone's HVX have a hard time keeping focus when you are zoomed in? Auto focus that is.

And on a side note, does anyone know how to tell a pal hvx from an ntsc hvx? Serial number maybe?

Cheers

Andzei Matsukevits · April 23rd, 2007, 07:57 AM

go to menu and check if it can record 50fps or 60fps.

Mine also has a big problem getting focus right.
My vx2100 was performing much better on this...

Robert Lane · April 23rd, 2007, 09:13 AM

Gene,

Auto-focus unfortunately is one of the weaker points on the HVX and, it's ability to react in AF is tied to the frame rate; it's more accurate and faster in higher frame rates, however the frame-rate tie-in is common among most digi-vid-cams I've shot.

Specifically, the HVX has a hard time doing any sort of follow-focus if the subject is moving towards or away from the camera and there has been many times that even with a non-moving subject in bright daylight that the AF has hunted back and forth and never found the subject. It's a very disapponting thing, but factual.

AF does have it's place as a "convenience" option however my suggestion is to never shoot AF and learn manual focus instead. The reasons are many:

- Just as with auto-exposure, the camera has no way of knowing exactly what your subject really is, and all it can do is supply you with it's best-guess based on whatever information is within it's AF/AE window which is almost always a changing target.
- If you ever plan on moving up to a shoulder-mount type of camera AF is not an option as all ENG cameras have manual focus lenses (the only exception to that is the F350, but you can't use your P2 cards in that).
- Many people think that all the reality shows are shot in AF mode since almost everything is in focus all the time; not true. 98% of "reality"-based TV is shot with ENG cameras - with no AF option - and shot very wide, which makes for extremely deep depth-of-field even at large aperture settings. These shooters are also very experienced with MF and know how to quickly rack-focus to accomodate quickly moving targets - but often you'll see the shooter hunt for focus too, just as the camera might have if it had an AF mode.
- AF can't help you if your subject is purposely off to one side - which is often the case in proper compositional techniques - and will instead lock onto whatever is frame-center.
- MF is the only way to assure that your subject never gets out of focus by AF attempting to re-acquire it's target.

Try using one of the many MF controllers on the market for the HVX: Varizoom ROCK PZFI; BeBob FOXI and a handful of mechanical follow-focus knobs and gears from Petroff, Chroziel, Zacuto etc. Trust me, after you learn the MF way you'll never trust AF again.

Gene Crucean · April 23rd, 2007, 10:24 AM

Thanks Robert. I agree with everything you said and I usually do manually focus. My problem is that we specialize in motocross films and if you know anything about motocross or shooting it, you'll understand why AF is necessary sometimes. It's all about being fast as hell and flexible while in the field. Everything is unscripted and impromptu. Not to mention it's direct sunlight which makes the lcd hard to see and the viewfinder is small and hard to pull focus. I'm starting to think a marshall mounted to a shoulder rig might be our only option with this focus issue.

Thanks Andzei. I know that but I was looking for more of a way to tell without looking/holding the camera, hence the serial idea.

Andzei Matsukevits · April 23rd, 2007, 11:17 AM

personally, i find it hard and unconfortable to pull a focus and hold a camera with other hand. On tripod - no problem. Handheld shooting needs two hands for stabilizeing(sorry for spelling) your shots, and there is no third hand for pulling the focus. At least it is what my experiences have said. Sometimes i shoot HVX on shoulder, LCD is too close, but for some time its ok and then i can pull the manual focus with free hand

Robert Lane · April 23rd, 2007, 03:30 PM

Just keep in mind, that when you see moto-x or any other moto or aviation sport with ultra-fast action that's broadcast it's with cameras that ALL have manual focus. It really comes down to training and practice.

However, as Anzdei points out the HVX and other handheld cams are very difficult to handhold and do anything manually - which is one reason why these cameras were over-loaded with auto everything. But, as always there are options.

Zacuto for example, makes the best solution for having multiple setups from one camera and makes it quickly convertible. Check out the homepage: http://www.zacuto.com. Watch the video demo on the homepage and you'll see a relatively new rig designed around their baseplate that converts the HVX - or any other handheld cam - from a tripod mount to a full-on shoulder mount with handgrips and tons of options for either mounting an external monitor, using the flip-out LCD or even the EVF and, have it all properly aligned with your eye. I have had one for a few months now and it works like a charm.

Put the ROCK PZFI controller on one of the grip arms and you've got quick and easily controllable manual controls for focus, zoom, iris and the stop/pause button. Or if you really wanted to get crazy, split the controls up with two different controllers, one hand controls focus/start/pause and the other zoom and iris. Which setup all depends on your own comfort level and shooting style.

Gene Crucean · April 23rd, 2007, 07:26 PM

Yes but also keep in mind when you watch motocross that you might be watching MY work :P

Zacuto is right down the road from me actually and I've been debating on getting a setup like that for a little while now. But for the record, my Z1 keeps focus perfectly. If you saw some of my footage with that cam you would probably have said I used manual focus on that also. But with that cam specifically I would pretty much always shoot with AF unless I wanted a specific rack focus or look.

Thanks for the info and advise btw. I'm gonna look into that ROCK controller.

Robert Lane · April 23rd, 2007, 08:15 PM

Quote:

Originally Posted by Gene Crucean

Thanks for the info and advise btw. I'm gonna look into that ROCK controller.

Just keep in mind the ROCK PZFI will only work with the HVX, not a Sony or Canon since they use LANC controllers which is very different.

Andzei Matsukevits · April 23rd, 2007, 11:46 PM

Gene, yes, i've been shooting with Z1 for some time some extreme sports and never had an issue with AF either

Robert Lane · April 24th, 2007, 07:22 AM

While testing all the handheld HD cams I owned a Z1 for a while and was impressed with many things, and it's AF performance was one of them. If it had been shooting DVCPRO-HD I would have kept it, no question.

David Lach · April 29th, 2007, 02:03 AM

Quote:

Originally Posted by Robert Lane

Just keep in mind, that when you see moto-x or any other moto or aviation sport with ultra-fast action that's broadcast it's with cameras that ALL have manual focus. It really comes down to training and practice.

To be fair though, those cameras have much better / higher res viewfinders / monitors for accurate focusing. The resolution of both the LCD flip out monitor and the viewfinder on the HVX200 made my life difficult on a few shoots where I had to quickly pull focus in difficult handheld shooting conditions. Not overly complaining, I know the limitations linked with the price point of those cameras, just saying.

April 23rd, 2007, 06:45 AM	#1
Gene Crucean Major Player Join Date: Mar 2006 Location: Los Angeles, CA Posts: 295	Funky focus when zoomed Does anyone's HVX have a hard time keeping focus when you are zoomed in? Auto focus that is. And on a side note, does anyone know how to tell a pal hvx from an ntsc hvx? Serial number maybe? Cheers

April 23rd, 2007, 07:57 AM	#2
Andzei Matsukevits Major Player Join Date: May 2005 Location: Tallinn, Estonia Posts: 300	go to menu and check if it can record 50fps or 60fps. Mine also has a big problem getting focus right. My vx2100 was performing much better on this...

April 23rd, 2007, 09:13 AM	#3
Robert Lane Go Go Godzilla Join Date: Nov 2004 Location: Scottsdale, AZ USA Posts: 2,825 Images: 15	Gene, Auto-focus unfortunately is one of the weaker points on the HVX and, it's ability to react in AF is tied to the frame rate; it's more accurate and faster in higher frame rates, however the frame-rate tie-in is common among most digi-vid-cams I've shot. Specifically, the HVX has a hard time doing any sort of follow-focus if the subject is moving towards or away from the camera and there has been many times that even with a non-moving subject in bright daylight that the AF has hunted back and forth and never found the subject. It's a very disapponting thing, but factual. AF does have it's place as a "convenience" option however my suggestion is to never shoot AF and learn manual focus instead. The reasons are many: - Just as with auto-exposure, the camera has no way of knowing exactly what your subject really is, and all it can do is supply you with it's best-guess based on whatever information is within it's AF/AE window which is almost always a changing target. - If you ever plan on moving up to a shoulder-mount type of camera AF is not an option as all ENG cameras have manual focus lenses (the only exception to that is the F350, but you can't use your P2 cards in that). - Many people think that all the reality shows are shot in AF mode since almost everything is in focus all the time; not true. 98% of "reality"-based TV is shot with ENG cameras - with no AF option - and shot very wide, which makes for extremely deep depth-of-field even at large aperture settings. These shooters are also very experienced with MF and know how to quickly rack-focus to accomodate quickly moving targets - but often you'll see the shooter hunt for focus too, just as the camera might have if it had an AF mode. - AF can't help you if your subject is purposely off to one side - which is often the case in proper compositional techniques - and will instead lock onto whatever is frame-center. - MF is the only way to assure that your subject never gets out of focus by AF attempting to re-acquire it's target. Try using one of the many MF controllers on the market for the HVX: Varizoom ROCK PZFI; BeBob FOXI and a handful of mechanical follow-focus knobs and gears from Petroff, Chroziel, Zacuto etc. Trust me, after you learn the MF way you'll never trust AF again.

April 23rd, 2007, 10:24 AM	#4
Gene Crucean Major Player Join Date: Mar 2006 Location: Los Angeles, CA Posts: 295	Thanks Robert. I agree with everything you said and I usually do manually focus. My problem is that we specialize in motocross films and if you know anything about motocross or shooting it, you'll understand why AF is necessary sometimes. It's all about being fast as hell and flexible while in the field. Everything is unscripted and impromptu. Not to mention it's direct sunlight which makes the lcd hard to see and the viewfinder is small and hard to pull focus. I'm starting to think a marshall mounted to a shoulder rig might be our only option with this focus issue. Thanks Andzei. I know that but I was looking for more of a way to tell without looking/holding the camera, hence the serial idea.

April 23rd, 2007, 11:17 AM	#5
Andzei Matsukevits Major Player Join Date: May 2005 Location: Tallinn, Estonia Posts: 300	personally, i find it hard and unconfortable to pull a focus and hold a camera with other hand. On tripod - no problem. Handheld shooting needs two hands for stabilizeing(sorry for spelling) your shots, and there is no third hand for pulling the focus. At least it is what my experiences have said. Sometimes i shoot HVX on shoulder, LCD is too close, but for some time its ok and then i can pull the manual focus with free hand

April 23rd, 2007, 03:30 PM	#6
Robert Lane Go Go Godzilla Join Date: Nov 2004 Location: Scottsdale, AZ USA Posts: 2,825 Images: 15	Just keep in mind, that when you see moto-x or any other moto or aviation sport with ultra-fast action that's broadcast it's with cameras that ALL have manual focus. It really comes down to training and practice. However, as Anzdei points out the HVX and other handheld cams are very difficult to handhold and do anything manually - which is one reason why these cameras were over-loaded with auto everything. But, as always there are options. Zacuto for example, makes the best solution for having multiple setups from one camera and makes it quickly convertible. Check out the homepage: http://www.zacuto.com. Watch the video demo on the homepage and you'll see a relatively new rig designed around their baseplate that converts the HVX - or any other handheld cam - from a tripod mount to a full-on shoulder mount with handgrips and tons of options for either mounting an external monitor, using the flip-out LCD or even the EVF and, have it all properly aligned with your eye. I have had one for a few months now and it works like a charm. Put the ROCK PZFI controller on one of the grip arms and you've got quick and easily controllable manual controls for focus, zoom, iris and the stop/pause button. Or if you really wanted to get crazy, split the controls up with two different controllers, one hand controls focus/start/pause and the other zoom and iris. Which setup all depends on your own comfort level and shooting style.

April 23rd, 2007, 07:26 PM	#7
Gene Crucean Major Player Join Date: Mar 2006 Location: Los Angeles, CA Posts: 295	Yes but also keep in mind when you watch motocross that you might be watching MY work :P Zacuto is right down the road from me actually and I've been debating on getting a setup like that for a little while now. But for the record, my Z1 keeps focus perfectly. If you saw some of my footage with that cam you would probably have said I used manual focus on that also. But with that cam specifically I would pretty much always shoot with AF unless I wanted a specific rack focus or look. Thanks for the info and advise btw. I'm gonna look into that ROCK controller.

April 23rd, 2007, 11:46 PM	#9
Andzei Matsukevits Major Player Join Date: May 2005 Location: Tallinn, Estonia Posts: 300	Gene, yes, i've been shooting with Z1 for some time some extreme sports and never had an issue with AF either

April 24th, 2007, 07:22 AM	#10
Robert Lane Go Go Godzilla Join Date: Nov 2004 Location: Scottsdale, AZ USA Posts: 2,825 Images: 15	While testing all the handheld HD cams I owned a Z1 for a while and was impressed with many things, and it's AF performance was one of them. If it had been shooting DVCPRO-HD I would have kept it, no question.