EIA 1956 resolution chart

The EIA 1956 Resolution Chart[1][2] (until 1975 called RETMA Resolution Chart 1956) is a test card originally designed in 1956 to be used with black and white analogue TV systems,[3][4] based on the previous (and very similar) RMA 1946 Resolution Chart.[5][6] It consisted of a printed chart filmed by a TV camera and displayed on a TV screen.[7] Inspecting the chart allowed to check for defects like ringing, geometric distortions, raster scan linearity, cathode-ray tube uniformity and lack of image resolution.[8][9] If needed, a technician could used it to perform the necessary hardware adjustments.

EIA 1956 video resolution target
Off-air photo of EIA 1956 test card being broadcast by TV Noordzee, 12 August 1964

Today, this chart continues to be used to measure image resolution of modern cameras and lenses and also in scientific research.[3][10][11][12][13][14][15]

Features and operation

The chart is composed of several features, each designed for a specific test:[16]

  • Large white circle: Allows for image geometry adjustments (image should be centered with the circles being perfectly round).
  • Vertical stripe boxes: A grating with a resolution of 200 Television Lines (TVL), a measurement of image resolution on analogue TV systems, allowing adjustment of horizontal linearity and geometry.
  • Horizontal stripe boxes: A grating, allowing adjustment of vertical linearity.
  • Grayscale steps: Evaluating gamma and transfer characteristics, they allow for contrast and brightness adjustments (at least 6 to 8 steps should be visible)
  • Concentric circles: Allow to test cathode-ray beam sharpness and focus
  • Resolution wedges: The gradually expanding lines near the center, labeled with periodic indications of the corresponding spatial frequency, allow checking of image resolution.
  • Border arrows: Allow for overscan adjustments.
  • Numbers: Going from 200 to 800, they correspond to TV Lines (TVL).

Used with early monochrome TV systems, this chart was useful in measuring image resolution, determined by inspection of the image as displayed on a CRT. On such systems an important measure is the limiting horizontal resolution, affected by hardware and transmission quality (vertical resolution is fixed and determined by the video standard used, usually 525 lines or 625 lines).

Usage

This test card was transmitted by NRK in Norway (in conjunction with the monochrome Pye Test Card G),[17] CKCK-TV in Saskatchewan, Canada (525-lines variant),[18] RTBF and VRT[19] in Belgium, NTS[20] in the Netherlands, Magyar Televízió in Hungary, TVP[21] in Poland,[22] American Forces Network in West Germany (525-lines variant, sometimes also with the centre portion overlaid on top of Multiburst test pattern),[23] Yugoslav Radio Television in the former SFR Yugoslavia, Rediffusion Television in British Hong Kong (where it replaced a modified version of the 1950s Marconi-designed Associated-Rediffusion "diamond" test card), Egypt and Syria.[24] It was also used by the pirate TV Noordzee station broadcasting to the Netherlands in the 1960s.[25]

This chart, in conjunction with later widescreen patterns, is commonly used to test consumer and professional standalone, smartphone and tablet cameras for photo and videography[11] and other imaging equipment like microscopes[8] or CCTV cameras.[10]

Variations

Recreation of Telefunken Test Card T05
A Philips "Starenkasten" 1952 TV set, displaying the Telefunken T05 test card.

Some variations of the EIA resolution test chart exist. In continental Europe,[26] a variation know as Telefunken Test Card T05[27] was used. It had five diagonal bars on the top left of the center white circle and different resolution wedges reminiscent from the RMA 1946 Resolution Chart.[16] It was used on ARD (from the 1950s up to the 1970s), Hessischer Rundfunk,[27] Bayerischer Rundfunk,[28] WDR,[29] NWRV in northern Germany,[30] Yugoslav Radio Television,[31][27] Österreichischer Rundfunk in Austria,[32] BRT[33] in Belgium, Doordarshan in India, Corporación Estatal de Radio y Televisión in Dominican Republic (525-lines variant; in conjunction with Indian-head test pattern), some commercial TV stations in Australia, Israel Broadcasting Authority and Israeli Educational Television in Israel, and in early-1950s trial television tests by the KTH Royal Institute of Technology in Stockholm, Sweden.[24] A modified Telefunken T05 test card was also used by Anglia Television, the ITV franchise holder for the East of England in the 1960s, designated as its own "Test Card B" (not to be confused with the BBC's never-aired Test Card B from the 1940s).[27][34]

See also

References

  1. Kang, Moon Gi (April 3, 2003). Selected Papers on CCD and CMOS Imagers. SPIE Press. ISBN 9780819451149 via Google Books.
  2. Sampat, Nitin; Yeh, Thomas (April 3, 1999). Sensors, Cameras, and Applications for Digital Photography: 27-28 January 1999, San Jose, California. SPIE. ISBN 9780819431219 via Google Books.
  3. "Standards for Visual Acuity June 15, 2006" (PDF). nist.gov.
  4. "Video Resolution Pattern (EIA-1956) Product Specifications" (PDF). imatest.com.
  5. "GJ's Home Page- Resolution test chart RMA 1946". home.kpn.nl.
  6. Bali, S. P. Bali, Rajeev. Audio Video Systems. Khanna Publishing House. ISBN 9788187522058 via Google Books.
  7. "Resolution Measured TV Lines". Causeway Security Solutions.
  8. "Stage Micrometers, Microscopy Calibration Standards, 2008" (PDF). dataoptics.com.
  9. "EIA-1956 Resolution Video Test Chart QA-70 – 登華資訊".
  10. Malone, T. (August 1, 1997). "VNIIEF NMPC and A Maintenance Management Conference -- video surveillance". OSTI 634045 via www.osti.gov.
  11. "Video Resolution Test Patterns". www.bealecorner.com.
  12. Liu, Yingli; Dai, Yijie; Shen, Fanqi; Yang, Lin; Ding, Zhanghao; Zheng, Zhenrong; Wu, Rengmao; Xu, Liu (March 28, 2022). "High-performance imaging with an advanced non-imaging lens based on full-path optical diffraction calculation in two-dimensional space". Optics Express. 30 (7): 11014–11025. doi:10.1364/OE.449685. S2CID 247388943 via opg.optica.org.
  13. Yang, D.X.D.; Gamal, A.E.; Fowler, B.; Tian, H. (December 3, 1999). "A 640/spl times/512 CMOS image sensor with ultrawide dynamic range floating-point pixel-level ADC". IEEE Journal of Solid-State Circuits. 34 (12): 1821–1834. doi:10.1109/4.808907. S2CID 35539716 via IEEE Xplore.
  14. Simova, Eli; Rochefort, Paul A. (July 3, 2015). "Ionizing Radiation Effects in Non-Radiation-Tolerant Commercial Video Cameras". 2015 IEEE Radiation Effects Data Workshop (REDW). pp. 1–6. doi:10.1109/REDW.2015.7336719. ISBN 978-1-4673-7641-9. S2CID 18380237 via IEEE Xplore.
  15. "Miniature and Mass-Producible Fluorescence Microscopes for Biomedical Imaging - ProQuest". www.proquest.com.
  16. Dhake, A. M. (May 1, 1999). TV and Video Engineering. Tata McGraw-Hill Education. ISBN 9780074601051 via Google Books.
  17. "Non-UK Television Test Cards, Tuning Signals, Clocks and Idents - Norway". January 12, 2016. Archived from the original on 2016-01-12.
  18. "EIA Resolution Chart 1956 CKCK- V". January 6, 2016 via Flickr.
  19. "Reception DX TV Belgique". dxtv.
  20. "Reception DX TV Pays Bas". dxtv.
  21. "Reception DX TV Pologne". dxtv.
  22. "Non-UK Television Test Cards, Tuning Signals, Clocks and Idents - Poland". January 12, 2016. Archived from the original on 2016-01-12.
  23. "Europesche-testbeelden, Radio Bulletin 1972". fmtvdx.eu.
  24. "Non-UK Television Test Cards, Tuning Signals, Clocks and Idents". January 12, 2016. Archived from the original on 2016-01-12.
  25. "TV Noordzee testbeeld, handige knutselaar ontvangt testbeeld via betonwijzer | Nationaal Archief". www.nationaalarchief.nl.
  26. "TV DX-ING FM DX-ING TEST CARDS, HS PUBLICATIONS, March 2018" (PDF). pdf-archive.com.
  27. "Television & Video: Test Cards & Signals - Telefunken, Jerome Glick". jeromeglick.net.
  28. "Reception DX TV Allemagne Baviere". dxtv.
  29. "Reception DX TV Allemagne Rhenanie du Nord Westpha". dxtv.
  30. "TV Service, PHILIPS TECHNISCHE BIBLIOTHEEK, 1962" (PDF). ubedata.wernull.com.
  31. "Testcards, Jugoslovenska Radiotelevizija - Radio Televizija Zagreb (JRT/RTZ) 1974". testcards.retropia.co.uk.
  32. "Reception DX TV Autriche". dxtv.
  33. "Reception DX TV Belgique". dxtv.
  34. "Reception DX TV Royaume uni". dxtv.


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