What is the Megavision EV System?

High resolution + Multispectral = EV system
The Megavision EV system is a revolutionary multispectral imaging system which captures high resolution, high dynamic range, and highly repeatable digital images. The EV system integrates two distinct imaging capabilities: High resolution photography and multi-spectral imaging.

Overcomes RGB limitations
While a standard RGB camera uses RGB  filters on the CCD to separate colors, a multispectral camera separates the light into several bands to overcome the limitation of the standard three bands covered by the RGB cameras.

Narrow band LED light
The EV system illuminates the objects with narrow band LEDs over a range of up to 12 wavelengths: 6 wavelengths of visible light for top quality color reproduction, and 6 wavelengths  of Ultraviolet and Infrared light for documentation and research purposes.
Unlike first generation multispectral systems, which uses filters to capture the spectral bands, the EV system captures the spectral bands by illuminating the object with small amounts of narrow-band LED lights to expose a highly sensitive, unfiltered monochrome sensor.

The MegaVision EV software

The software to control the EV system is MegaVision’s PhotoShoot.
This advanced solution has been developed for Hyperspectal imaging since 2005 and controls all aspects of the hyper spectral imaging automating the capturing process to a degree that the capture is done with a single click.

Photoshoot:

  • Automates the capturing of multiple images
  • Controls light, shutter, aperture, wavelength, and the optional color wheel
  • Live focus for efficient composing and focusing
  • Flat field features eliminates uneven light
  • Generates color image from visible-light-captures
  • Processes the images into CIELab based color files, which are ideal for archiving and reproduction.

Database compliance gives efficient workflow

PhotoShoot implements metadata support based upon EXIF and IPTC standards which may be customized to embed database information directly into the image files.  PhotoShoot enables automatic naming and organizing of captured images based on associated metadata.

The MegaVision EV camera system

The EV Camera, which includes MegaVision’s Monochrome E7 50-megapixel back, computer controlled shutter, computer controlled aperture, a hyperspectral lens, and purpose-built technical camera body is at the heart of the EV multispectral system. Each element of the EV camera is designed to provide meticulous control and solve imaging problems encountered when imaging priceless objects of great importance over a large spectral range. One camera system for monochrome, RGB multishot and hyperspectral shooting.
Some key metrics of the EV camera performance:

  • Digital Back: MegaVision 50 megapixel E7 Monochrome, rotates to any angle
  • Camera Body: rail and bellows, 13 cm travel, standards fixed co-axial to optical axis, rear standard focusing.
  • Lens: Any Copal-0. Recommended: MegaVision’s unique 120mm f4.5 hyperspectral; Parfocal with execllent sensitivity from 350 to 1,000 nm.
  • Shutter: Copal-0, 7 leaf, 1/60 to 60 seconds, computer controlled and powered via USB, rated for over 1 million exposures.
  • Dynamic Range: 12 bits per channel: 14bit ACD
  • File Size/wavelength: 100 Mbyte/channel at 16 bits, 50 Mbyte/channel at 8 bits.
  • Capture Rate: One image frame per 2 seconds, subject to illumination constraints.
  • CCD Array: 8176 x 6132 pixels, 6.0 micron pixel size.
  • Connectivity: Gigabit Ethernet
  • Options: Color filter wheel, lens shade, 2nd “focus keeping” rail, laser alignment bar

EV™ LED Illumination System

A revolutionary EV™ LED illumination system provides unprecedented opportunities in imaging and image quality. This system enables imaging in multiple distinct narrow spectral bands or combinations of spectral bands over a range of wavelengths from the near ultraviolet to the near infrared.
The lighting system is fully integrated with MegaVision’s Photoshoot™ software and typically includes LED’s with 10 to 20 specific wavelengths, for example:

  • UV 365, 395 nm
  • Visible 420, 445, 470, 500, 520, 560, 590, 620, 630, 650 nm
  • Infrared 700, 735, 780, 860, 940, 1050 nm

Choice of 1 or 2 different spectral bands for raking illuminators.

Advantages of LED illumination

  • High efficiency reduces heat and stress on the objects in the scene.
  • Elimination of unwanted IR wavelengths prevents registration difficulties caused by object motion due to heating.
  • Because narrow-band LED’s emit no light outside the specified band, there is no need to filter IR light from the sensor. The IR cutting filter can be eliminated. Eliminating the IR filter removes an optical element from the image forming path and substantially increases light efficiency, enabling reduced exposure and greater S/N.
  • EV LED’s provide highly specific, low maintenance, and very repeatable light. Panel spectral properties are consistent from shot to shot and year to year. Lumens/watt is stable.
  • Normal lifetimes of up to 50,000 hrs.
  • Rapid switching times (< 50 µSec) allow pulse width modulation and precise exposure durations.

EV lenses 120mm f/4.5 Macro for photography in UV, IR and visible light

The MegaVision 120mm f/4.5 Macro UV-IR Apochromat is an innovative view/technical camera lens that incorporates both floating element and advanced UV-VIS-IR apochromatic color correction technology. Six ED glass elements and one aspheric element are used to achieve an unprecedented level of performance for multispectral documentation, forensics, scientific imaging, and fine-art photography.

Same focus plane at all wavelength 
After setting focus in visible light, no refocusing is necessary for either ultraviolet or infrared imaging, thus enabling extremely precise color channel registration in multispectral applications. The excellent color correction is also valuable in visible light photography because it completely eliminates the purple fringing suffered by other lenses in high contrast outdoor scenes. The adjustable floating element, unique among view camera lenses, ensures superb optical correction at all object distances.

Specifications:

● Focal length 120 mm       ● Aperture range f/4.5 to f/45
● Waveband 320 to 1100 nm
● Image circle  f/4.5 70 mm    ● Image circle f/16 100 mm
● Length 118 mm   ● Max. diameter 75 mm
● Weight 726 grams
● Min. object distance 0.47m   ● Max. image scale 1:1
● Shutter Copal #0