safelight

• safelight:

  • provides enought light to illuminate the darkroom while ensuring that the film remains unexposed
• composition of safelight:

  • incandescent lamps with a color filter
  • LED lamps
• wattage of safelight: 15W
• distance of safelight: no closer than 1.5m (5ft) from the workspace
• physics of light: frequency is inversely proportional to wavelength
• red: long wavelength 700nm = lower light frequency
• violet: short wavelength 400nm = higher light frequency
• safelight filters: used because both radiographic and photographic film are sensitive to the wavelengths and energies that comprise most of the electromagnetic spectrum of both light and x-rays
• Kodak WS 6B filter:

  • amber filter (reddish yellow)
• Kodak GBX filter:

  • red filter
• Kodak WS 6B filter:

  • emits orange brown light
• Kodak WS 6B filter:

  • transmits light that has a wavelength longer than 550nm
• Kodak WS 6B filter:

  • used for blue-sensistive film only (monochromatic film)
• Kodak WS 6B filter:

  • causes fog to green sensistive film
• Kodak GBX filter:

  • emits dark red light
• Kodak GBX filter:

  • transmits light that has a wavelength above 660nm
• Kodak GBX filter:

  • used for green and blue sensistive film (orthochromatic film)
• Kodak GBX filter:

  • used only for direct illumination(low intensity of light)
• spectral matching: refers to the compatibility of a safeligh filter to the color sensistivity of the film