Best D800 focus mode?

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WayneF

Senior Member
Any ideas about best video focus mode? I'm using the Wide Area AF choice, but panning the camera around is the pits, from all the seeking back and forth.

I know all the reasons that is very difficult, but little camcorders do much better. I know their tiny lens and sensor gets near infinite depth of field which hardly needs to focus - the DSLR cannot compete, it has much more focusing work to do. And I know contrast focusing is pitiful, but they both have that, and the D800 has such a faster processor. I guess a lot more pixels too, I don't know when focus is done. I know panning the camera around is a no-no, Hollywood goes to great lengths to minimize that.

But there must be a focusing technique better than I'm seeing? :) I'm just relying on Wide Area AF. Is there any logic that DX mode would help (reducing pixels?) It is subsampled anyway.
 
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gqtuazon

Gear Head
I just place the lens in manual focus. Lens will hunt if you leave it in auto which is very annoying.

Somehow you get more dof in video and the ISO is much more forgiving.


Sent from my iPhone.
 
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WayneF

Senior Member
It certainly is annoying. :) I have seen it use ISO 5000, and it seemed very acceptable. I guess video is only shown for 1/30 second, and then you get a new picture with different noise, and it guess it doesn't register well. I was assuming D800 high ISO was a big advantage, however, Thom Hogan says than since D800 video is subsampled (reading only every third raw scan line, and then resampling even smaller), that the FX noise advantage is much reduced. He claims video ISO 1600 looks more like ISO 6400 in stills. I don't see that myself. Probably it is about one individual frame?

It made wonder though, if subsampled, then DX size would probably be as good (still too many pixels, but maybe more depth of field), and maybe the fewer pixels could be faster, maybe focus could analyze it faster ? Hogan claims the FX and DX size, combined with JPEG Large, Medium, Small, gives six possible sizes for Live View Video - all of which are larger than the final 1920x1080. I don't know how to verify that about JPEG, or why it matters, since we only see the final size.

So, not relishing wading into that, I wondered if anyone else has visited there? Can it speed up focus?
 
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gqtuazon

Gear Head
WayneF said:
It certainly is annoying. :) I have seen it use ISO 5000, and it seemed very acceptable. I guess video is only shown for 1/30 second, and then you get a new picture with different noise, and it guess it doesn't register well. I was assuming D800 high ISO was a big advantage, however, Thom Hogan says than since D800 video is subsampled (reading only every third raw scan line, and then resampling even smaller), that the FX noise advantage is much reduced. He claims video ISO 1600 looks more like ISO 6400 in stills. I don't see that myself. Probably it is about one individual frame?
Click to expand...

Here is a video sample that I took about 9 months ago. Virtual Horizon concert.

D800E, Sigma 85mm f1.4 HSM @ f1.4, 1/50, ISO 3,200, ME-1 mic and monopod
I think it is very acceptable and even at f1.4, both musicians were still in focus.

 
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