The PCT670-INF is an all-encompassing solution for your lighting techniques, including brightfield, darkfield, and phase contrast. Designed for the T670, T750, and FM820T series microscopes, this kit provides all of the tools necessary for use with phase contrast, darkfield, and brightfield. Phase contrast is used to reveal detail in indistinct objects, such as unstained cells and microorganisms that would otherwise appear invisible. By using a combination of specialized objective lenses and a modified light condenser, these invisible objects can be visualized by manipulating variations in phase. Darkfield is a simpler method for inreasing contrast in hard-to-see specimens. Although it does not provide as much detail as phase contrast, it produces a more extreme level of contrast which is especially useful for certain applications such as cell counts. The turret condenser not only provides the annuli needed for phase contrast, but also brightfield and darkfield settings. This versatility makes life a lot easier by allowing you to switch between lighting methods by simply rotating a dial. The turret has two centering dials for proper alignment of phase-contrast and darkfield settings. A telescopic centering eyepiece is also included for precise alignment, guaranteeing optimal results. For monochromatic viewing, a green filter is provided to limit light to the central portion of the spectrum. Four plan-achromatic objective lenses are included, each equipped with a phase ring. These provide sharp, high-contrast images at magnifications from 10X to 100X. Specifications Condenser Mount: Front mount Mounting Diameter: 37mm Model Compatibility: T670, T670Q-PL, T750, FM820T Condenser Type: Turret design with phase contrast, darkfield, brightfield Numerical Aperture: 1.25 Immersion Medium: oil Centerable: Yes Phase Contrast Settings: 10X/20X, 40X, 100X Objective Lenses: 10X, 20X, 40X, 100X Objective Lens Optical System: Infinity-corrected Objective Lens Mounting Thread: RMS 20.32mm Objective Lens Parfocal Distance: 45mm Contents: One turret condenser Four objective lenses (10X, 20X, 40X, 100X) One centering telescope One green filter