April 2010 Newsletter

Now Available – Infrared Test Charts

Imatest’s new Infrared SFRplus test charts support testing of visible light through Medium Wavelength Infrared (MWIR). The large charts have a sturdy aluminum substrate and are suitable for outdoor field testing, as well as lab testing. Details here.

Imatest Master 3.6

Imatest has added four new modules.

• • Find Sharpest Files
  • This module allows you to quickly rank images by the sharpness of a cropped region. Any set of images, including but not limited to test charts, taken of the same subject under similar lighting conditions, can be compared. An example might be several photographs of a flower, taken in a slight breeze, or photographs of any subject taken at different f-stops or using different focusing approaches (auto and manual). The sharpness results do not correspond to any standards— they are only for comparing a particular batch. They represent overall, vertical, and horizontal, and overall edge sharpness.
  • Blemish Detect
  • This module detects sensor blemishes, using filtration and threshold settings based on the human visual system (HVS). In essence, the HVS is a bandpass filter that rejects very low and high spatial frequencies, and also has a minimum threshold for detecting density differences. Blemish Detect has a sophisticated utility for viewing and setting the filter settings so that sensors with blemishes that are visible to the human eye (under a realistic range of viewing conditions) will be rejected, but sensors with invisible (subthreshold) blemishes will pass. This can maximize yields in manufacturing testing.
  • Uniformity-Interactive
  • This module performs the same measurements as Light Falloff, but with a fully interactive interface. Measurements include lens vignetting (dropoff in illumination at the edges of the image), color shading, and other image, illumination, and sensor nonuniformities. The interactive interface allows it to directly acquire images from sensor development systems using the Imatest Image Sensor edition— valuable for setting vignetting and color shading correction registers in image sensor chips.
  • Wedge (a part of Rescharts; Master-only)
  • This module measures the MTF (Modulation Transfer Function) and the onset aliasing (related to the vanishing resoultion) from converging bar patterns, called “wedges”, which are a part of many popular resolution test charts. “Hyperbolic” (linear in frequency) wedge patterns are central to the CIPA DC-003 standard for digital camera resolution measurement, which will be incorporated in a revision of the ISO 12233 resolution measurement standard.

• Generalized raw read capability enables noncommercial raw files (not supported by dcraw) to be read. We are happy to work with any customers who have raw file formats to decode.
• A new Lens-style MTF plot is similar to MTF displays in the Canon, Nikon, and Zeiss websites.
• Batchview can display lines as well as bars.
• Data Cursor (now available in all Figures) displays fine details of plot values and image pixels. It is available in all Figures and most interactive modules (Rescharts, Multicharts, etc.).
• Multiple 3D plots can be produced by SFRplus (running in auto mode).
• Diffraction-limited MTF is displayed in SFR and SFRplus MTF plots when the pixel spacing is entered.
• Angular frequency (cycles/milliradian and cycles/degree) is available for MTF measurements.
• A new page shows the relationship between MTF Curves and Image Appearance.

Recent News

Imatest Consulting

Is your company in need of short-term expertise to help solve challenging technical problems? If so, consider Imatest Consulting Services. We have expanded our consulting staff to offer our customers an even greater range of expertise.

Informational Videos Now Available

Do you have colleagues who would appreciate a quick overview of Imatest software and test charts? If so, please direct them to our new videos page. Additional videos will be added frequently over the coming months.