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Rough environment operations incl. diver beach insertion and reconnaissance from sea:
Portability and the ability of the lens to withstand shock, dirt and water may be of great concern. Use tough and lightweight
FrogEye™ FL-400 lens. Lens collapses and transports under water without protection. Extend lens prior to surfacing,
then surface and wait 2-3 seconds for water to drain. Shoot and submerge.
Underwater Use
Use very short focal length lens such as Canon EF 14mm or Sigma EF 15 mm to maximize the field of view. Due to poor
water quality, you will probably operate within a few tenths of a meter to a few meters of the target
Night Vision
The speed of the lens (low F number) is critical. Reducing focal length in favor of lens speed is often called for.
Filter Selection
FrogEye™ operates with visible, near-infrared (NIR) and ultraviolet (UV) light. This capability can for example be used to
better detect camouflaged personnel and equipment. However, the different wavelengths also focus differently, and thus
use of a filter to select the desired spectrum is necessary in order to obtain sharp images. (Images taken without a filter at
daylight will be somewhat blurred). Filters screw to the lens filter port. You must specify the filter size to match the lens.
Note: The FrogEye FL-400 lens has a built-in IR-cut filter for visible light operations. No filter is required.
•
For
visible light
operations, use a Hot Mirror (IR-cut) filter such as Tiffen ‘Standard Hot Mirror’
•
Near Infrared (NIR)
imaging helps detect personnel and equipment camouflaged in a life vegetation background.
Use an IR filter such as Hoya Infrared R72.
•
UV Imaging
helps detect some types of snow camouflage against a snow background. Use a UV filter such as
Hoya U-330 (broad band UV), Hoya U-340 (medium band UV) or Hoya U-360 (Narrow band UV).
Life vegetation appears bright in near infrared (NIR) images
