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Old September 26th 08, 07:02 PM posted to rec.photo.digital,rec.photo.digital.point+shoot
carlislestamford
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Default Infrared photography

On Fri, 26 Sep 2008 07:45:14 -0700, DaveC wrote:


I'm unclear whether you hacked your camera. Did you remove the IR filter from
the image sensor? Or did you just add IR filters to your lens?


No need to remove any internal filter or hack these cameras. Just screw-on
standard IR filters to the front of the lens to cut out any visible light. They
come with a built-in infrared photography mode in them. Along with the usual use
for a digital camera, these were designed with their "Night Shot" mode. When you
turn the switch to that mode the camera flips its internal IR filter out of the
way, the one that everyone else has to hack out of their camera and end-up
destroying it for normal photography. The camera then readjusts the focusing
distance to account for IR wavelengths only and turns on some high-power IR LEDs
in front to illuminate subjects in the dark. You can then see, photograph, and
video-record in the total dark with it. I recall during a night-hike one time
that my headlamp batteries went out so I used my Sony camera like a night-vision
scope to find my way down a precarious outcrop of rock. Looking through the
camera's viewfinder for my next safe perch to land on.

These are also the only cameras that can quickly auto-focus in complete dark.
Along with their "Night-Shot" mode they also have what is called their "Night
Framing" mode. It uses the IR mode with its IR LED floods for you to focus and
frame a shot in the total dark, undetected, but then fires the flash for
properly exposed full-color images.

I also obtained two inexpensive (~ $30-$40 USD) high-power IR floods that Sony
sells for their "Night Shot" capable digicams and videocams. Model # HVL-IRM.
They attach to the hot-shoe but also come with an extender plate so you may
attach it to the tripod socket and have it alongside of instead of on top of the
camera, or use it to stack/gang more than one. They use the same Li-Ion battery
as used in the camera or you can use 2 AAs with them, a switch on the IR flood
to select which power source you want. A full charge, when using either battery
source, seems to last forever. They also have a continuous adjustment dial for
how much IR light level you want. I use those two floods (along with the
camera's built-in IR LEDs) to photograph and take videos of nocturnal wildlife
from as far away as 60 ft. in the total dark. The animals see and hear nothing
while being recorded but you can see your subject clearly in the viewfinder by
the IR light alone. It's the only way to photograph and take video of nocturnal
wildlife without your presence changing their natural behavior. If you put the
ISO mode to Auto then when in "Night Shot" mode the camera will crank up the
gain to ISO3200 when needed. It is grainy but perfectly acceptable for an IR
night photo. It looks like using high ISO film. Images at ISO3200 also clean up
very nice with good noise-removal software. Since it will be a B&W image when
done any color noise is averaged out. You can of course still use all the
manually set low ISOs too for noise-free IR images at night. You would use
ISO100 or 200 for daytime IR photography.

One interesting aspect of IR photography that I didn't know. I was photographing
some vast forest fires in the Rocky Mountains. The haze from the smoke for
hundreds of miles was making seeing the tops of any distant mountains impossible
during the many weeks that we were camping/hiking/kayaking in the area. Putting
on that filter-stack on my Sony camera, clicking the camera into "Night Shot"
mode in the daytime, I could then look through the camera's viewfinder to see
all the invisible distant mountain-tops and glaciers right through all that
dense haze. Appearing just as crisp and clear as if there were no fires. It was
pretty neat to be able to see what nobody else could see at the time. It
afforded some unique images that nobody else could get. Photos of the forest
fires right along with the usual majestic mountain scenery and glaciers.
Everyone else was just getting shots of fires, dense smoke, and nearby hazy
hills that could have taken place nearly anywhere on the planet. My photos
clearly showed where these fires were. They also look all the more artistic and
interesting with the mountain peaks towering over their immense fires below.

While hunting on the net just now for something, I notice that this year's Sony
Cybershot DSC-H50 also has "Night Shot" mode in it, for about $350.

Clipped from that page online:

Sony Cyber-shot DSC-H50 Digital Camera (Black)
9.1 Megapixel
15x Optical Zoom
3.0" Tilt-up LCD Display
Super SteadyShot Image Stabilization
Face Detection with Smile Shutter
High Sensitivity (ISO 3200)
NightShot Infrared System
HDTV Compatibility