# The SuperCOSMOS Sky Survey. Paper II: Image detection, parameterisation, classification and photometry Source: [The SuperCOSMOS Sky Survey. Paper II: Image detection, parameterisation, classification and photometry]() Collection index: [llms.txt]() Data updated: 2025-10-24T19:41:19.139Z Authors: Nigel Hambly, Mike Irwin, Harvey MacGillivray (1) \_\_INSTITUTION\_3\_\_ Wide Field Astronomy Unit IfA University of Edinburgh, (2) Cambridge Astronomy Survey Unit IoA Cambridge University) Published: 2001-08-17T14:28:26.000Z ## Abstract In this, the second in a series of three papers concerning the SuperCOSMOS Sky Survey, we describe the methods for image detection, parameterisation, classification and photometry. We demonstrate the internal and external accuracy of our object parameters. Using examples from the first release of data, the South Galactic Cap survey, we show that our image detection completeness is close to 100% to within 1.5 mag of the nominal plate limits. We show that for the Bj survey data, the image classification is externally \> 99% reliable to Bj = 19.5. Internally, the image classification is reliable at a level of \> 90% to Bj=21, R=19. The photometric accuracy of our data is typically 0.3 mag with respect to external data for m \> 15. Internally, the relative photometric accuracy in restricted position and magnitude ranges can be as accurate as 5% for well exposed stellar images. Colours (B-R or R-I) are externally accurate to 0.07 mag at Bj = 16.5 rising to 0.16 mag at Bj = 20. ## Recorded benchmark results A research result applies to its stated dataset, split, metric and evaluation configuration. Compare like-for-like settings, preserve the metric's unit and direction, and distinguish paper-reported results from independent reproduction. The best result recorded here is not a claim of exhaustive, current global coverage. ## Original sources and implementation [Original paper]() [PDF]()