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#1 petersant

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Posted 01 February 2009 - 01:16 PM

Hi,
I am currently planning a shoot. This is a single shot lasting around ten minutes. The camera, an Arri BL 16, will be travelling through a maze of streets, this will be shot in early hours of the morning. I figured as I will the only person operating the camera that I set the lens to 'Hyperfocal Distance' in order to get as much in focus as possible (and make my life easier). This is also the 'look' I am going for.

The lens I am using is an 'angenieux 12-120' can anyone advise me on how I go about ding this or calculating this?
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#2 Scott Lovejoy

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Posted 01 February 2009 - 02:08 PM

I believe that one way you could do it would be to consult a DoF chart.

Basically you're trying to get a long DoF, so f-stop, lens choice, focal distance all factor in.

With 16mm film you could focus at 8 feet, aperture set to f/11, with a 20mm lens and you'll have focus from 3' 11.4'' to Inf.
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#3 Edgar Dubrovskiy

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Posted 01 February 2009 - 03:51 PM

http://dofmaster.com/doftable.html

At 2.8 (how 'early' is the morning? ;) 12mm lens will give you 5'9'' to ∞, when set at 12'.
Pretty usable. Basically, the wider you go, the better.
Plus, f-stop, of course.

Edited by Edgar Dubrovskiy, 01 February 2009 - 03:52 PM.

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#4 Brian Drysdale

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Posted 01 February 2009 - 03:55 PM

I believe that one way you could do it would be to consult a DoF chart.

Basically you're trying to get a long DoF, so f-stop, lens choice, focal distance all factor in.

With 16mm film you could focus at 8 feet, aperture set to f/11, with a 20mm lens and you'll have focus from 3' 11.4'' to Inf.


Early in the morning, you mightn't get that sort of stop. I'd tend to keep at 12mm, especially if this "travelling" though a maze of streets is handheld with an Arri 16BL.

The charts will give you the hyperfocal distance. However, it really depends if you're filming just the streets, or someone/something moving through the streets or moving into objects/people in the streets and how close these get to the camera.
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#5 petersant

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Posted 01 February 2009 - 08:03 PM

Early in the morning, you mightn't get that sort of stop. I'd tend to keep at 12mm, especially if this "travelling" though a maze of streets is handheld with an Arri 16BL.

The charts will give you the hyperfocal distance. However, it really depends if you're filming just the streets, or someone/something moving through the streets or moving into objects/people in the streets and how close these get to the camera.


Firstly, thank you all for your help. Also, just a quick note that I will just be filming the streets there will be no characters. I will be walking along a fenced path/maze using an Arri BL16 on an Arri shoulder Brace.
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#6 Brian Drysdale

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Posted 02 February 2009 - 04:43 AM

Firstly, thank you all for your help. Also, just a quick note that I will just be filming the streets there will be no characters. I will be walking along a fenced path/maze using an Arri BL16 on an Arri shoulder Brace.


I think much will depend how close you're getting to these objects, how important they are compared to the distant objects and where you wish the eye to be directed. It's basically a balancing act. The DOF tables will help make you a judgement, fortunately, on a 12mm you've got a large DOF.

I hope you're relatively fit, doing a 10 min moving shot with a 16BL on a shoulder brace doesn't sound like my idea of fun.
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Visual Products

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Metropolis Post

Aerial Filmworks

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