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Old July 25th, 2011, 02:38 PM   #31
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Re: Keeping focus of fast moving objects

John,
First the cameras aren't along pit road. They are mounted to the outside wall generally 2 along each straightaway, and 1 per corner just to the inside radius or the turn. There are also others, such as on the flagstand or top of the fence just beyond the flagstand. There are all robotically operated from as much as a 1/4 mile away in the broadcast corral. Keeping focus on the cars is actually pretty easy. First keep in mind the cameras and lenses aren't prosumer. The cameras themselves are around 25 to 30 thousand each, the lenses, probably not much less than that and they are anywhere from a 22X to a 40X depending on the track and the position of the camera. For the flagstand and pit out they might be a short lense, maybe 16X since it's a pretty short area to work in.
Find a spot about 1/2 way down the track set focus, of course making sure the backfocus is spot on, usually running a pretty small aperture, f/16 up to f/32 if conditions call for it. Keep in mind this is controlled in the video truck, we as operators have no control over that. In just about every case the depth of feild covers down to the previous turn and back to the next turn. Sometimes though, depending on the track, you will be pulling focus and most of us tried to keep that to when we followed a car thru the turn until the director called the next shot. I liked the motorcyle twist "throttle" type of focus mechanisim some guys preferred the "wheel" type of fucus mechanisim. At first it's daunting even with my experience as both a still photographer doing sports and a videographer doing sports. Trust me there are times you just can't keep up with the focus and zoom at the same time. It gets rather raucous in the trailer with 4 to 6 operators in there running these cameras but you communicate with one another all whille listening to the director "talking in your ear"...That's one reason we would get to the track on Tuesday or Wednesday for a Friday race. Setup and fax everything out, then everytime anything but a golf cart was on the track, even when we weren't on the air, I would practice, practice practice. Making sure my focus was right, practicing zoom and focus thru the turn and holding the shot until called off. It was a fun time and a real pleasure to wrok with some of the guys that had been doing it for lots of years. Learned a lot from that experience. It can be done.Plus there wasn't a camera out there that had any kind of auto focus. Next time NASCAR is running watch the race for a while on TV, you'll see what I mean.
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Old July 26th, 2011, 07:58 PM   #32
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Re: Keeping focus of fast moving objects

I have been been recording Aussie Rules football matches on and off over the last couple of years with a HV20 and have been looking at upgrading to the NX5 in order to do this in a more serious manner.

Given that the action can quickly move from just 10 feet away to more than 500 feet away, that I use an external monitor and I need to have one hand free, the autofocus is very important for me. Does anyone think that the NX5 would or would not be suitable? Or are there any other cams I should be looking at?

I have not had any issues with the autofocus on my HV20 but I want a camera that has better zoom capability, is not tape based and is more professional in both looks and capability. The ability to record in either mpeg2 SD or AVCHD seems very handy as well, but I do require HD capability.
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Old July 26th, 2011, 11:51 PM   #33
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Re: Keeping focus of fast moving objects

Hi Graeme,

A mate of mine (with occasional help from myself) shoot AFL up here in Brisbane and the Gold Coast, using the Sony V1s. This is for both local club matches as well as the bigger Queensland matches that are replayed on Foxtel.

The NX5 that I was talking about at the start of this thread is one that he purchased as an additional camera for shooting AFL and the autofocus just isn't good enough to keep up with the fast paced action.

Also, despite the camera having 20x optical zoom, because the sensor block is bigger/wider, the full zoom doesn't go as far in to the action as it needs to be. Certainly not when compared to the V1s being used.

So it's back to the tape based V1s for shooting AFL. If you're still sure that you want an NX5, he may well sell it to you. :-)

Andrew
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Old July 27th, 2011, 12:16 AM   #34
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Re: Keeping focus of fast moving objects

Thanks Andrew,

I was hoping you had been shooting AFL, but it's disappointing to hear that about the autofocus. Had you tried turning macro focus off? Other threads had suggested this improved things.

I understood that the zoom wasn't going to be as strong as the 20x may have indicated, but at least it would have been better than the 10x on my HV20 - otherwise The NX5 was looking to be perfect for my needs. A slightly off topic question - is the NX5's mpeg-2 format dvd compliant (ie does it need re-encoding)?

Cheers (and thanks),
Graeme
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Old July 27th, 2011, 02:02 AM   #35
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Re: Keeping focus of fast moving objects

I haven't been shooting AFL with the camera (but love its low light sensitivity!). No idea if it has been tried with the macro off. The camera is being used at an AFL carnival at the moment and I've texted through the tip. I'll update this thread if it turns out that it helps.

I haven't shot to mpeg2 yet with the camera so I can't tell you if it needs transcoding for DVD or not. I've stuck with the AVCHD format as part of my being a bit of a quality freak.

Got a feeling that the 20x zoom on the NX5 will definitely be better than the 10x zoom you have been using. :-)

Andrew
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Old July 27th, 2011, 06:57 AM   #36
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Re: Keeping focus of fast moving objects

Quote:
Originally Posted by Graeme Walker View Post
I understood that the zoom wasn't going to be as strong as the 20x may have indicated.Graeme
Not quite sure what you mean here Graham. I'm pretty sure that within the production tolerances the NX5's G lens does indeed have a 20x zoom ratio. The V1 beats it on the telephoto end, but it does this by having a poor wide-angle coverage.

And although I don't shoot sports, I can confirm that the NX5's auto-focus isn't a patch on the Z1's. Odd, that.

tom.
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Old July 28th, 2011, 09:50 PM   #37
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Re: Keeping focus of fast moving objects

Tom - as you mention, the NX5 starts wider than the V1 (and my HV20). On full zoom the NX5 goes to 590mm, whereas my HV20 goes to 435mm, so that would still an improvement for me.

I was thinking that this camera would be perfect for my needs so I'm pretty disappointed. I don't think that there is currently anything else out there with the same potential - tape-less, 20x zoom, avchd & mpeg-2, manual controls etc.
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Old July 29th, 2011, 01:51 AM   #38
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Re: Keeping focus of fast moving objects

Your words neatly sum up why I bought an NX5 Graham. 'nothing else out there with the same potential - tape-less, 20x zoom, avchd & mpeg-2, manual controls etc'. There are compromises we must make in all walks of life, and the NX5 is one of the better ones in my view.
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