Filming heat sensitive images?

M

maheshshimpi

New member
Hello Friends,

I am shooting a short film. Its mostly night outdoor shoot.
I have to do a shot where a person is supposedly watching couple of people through the night binoculars. These characters are chasing one another.

1. How do I show the heat sensitive images?
2. Is this do-able in post production editing effects? If yes, then do I shoot regular and let it be taken care off in editing?

Look forward to your opinions/ideas/techniques etc.

Thanks
Mahesh
 
If you are going to try and do it in post, you might consider having your actors wear brightly colored full bodysuits, with hoods. Like maybe all orange like you'd find in a sporting goods store.

That way you can isolate their imagery from the background, and then superimpose coloring on top of that. Sort of the reverse of a green screen. something like this: http://www.hellogreenman.com/
 
Electronic night binoculars usually include a video out plug, so just record off that. And many video cameras also have a night vison mode.

I'm dubious about faking it in post, I've seen it faked badly too many times (ditto for infra red photography)
 
I second doing it for real if you have the actual equipment. It will look faked in post almost certainly. It's possible to do it in post, but hard to do right.
 
maheshshimpi said:
Hello Friends,

I am shooting a short film. Its mostly night outdoor shoot.
I have to do a shot where a person is supposedly watching couple of people through the night binoculars. These characters are chasing one another.

1. How do I show the heat sensitive images?
2. Is this do-able in post production editing effects? If yes, then do I shoot regular and let it be taken care off in editing?

Look forward to your opinions/ideas/techniques etc.

Thanks
Mahesh
Click to expand...

If you don't have access to real night vision equipment, you can try various experiments.

The devices use an element called an image intensifier, and as such, produces a 'soft' image. The sensors are monochrome, so any 'color' tha one would see in some image has been processed to a 'false color' form. For infrared images the 'false color' lookup table is arranged such that things that are 'brighter' in the image may have a 'reddish' cast, to sort of correspond to our human preception of 'warm/glow/red'... things that are darker are given a 'bluish' cast.

In the case of 'night vision' devices for humans the color used is predominantly green, most likely becuase the human eye is more sensitive to green.

Because of the use of the image intensifier, the amplification of the low light level results in an image that has a lot of noise, and so the image appears more 'grainy', and has variation over time.

You might try shooting at night say a DVX100 with max video gain and very low light, then process to a 'green' monochrome, and add a bit of bluring. The problem there is the 'grain structure' of the image is 'sharper' and a bluring of the noisy video image would not give
the same effect, so you may have to figure out how to superimpose a 'sharp varying grainy' structure on the blured 'night vision' image...



As a note, the sensor technology used in digital cameras is more sensitive to near-infrared, and a filter is used to eliminate that from image that the sensor acquires. There are various sites that will indicate how some still cameras can be modified by removing the filter, to have better near-infrared characteristics. I'm not aware of any similar modification for video cameras... but it is a 'distructive' process... so once modified, the camera would be only good for this specialized use.
 
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