VIRCAM Exposure Time Calculator: Release Notes

• 2004-12-24: Original Release
  1. Basic all-perl functioning prototype, all instrument data represented by simple functions.
• 2005-05-25: "C" version:
  1. Main computational body translated to C language for ESO deliverable.
• 2005-12-23 version 1.0:
  1. Incorporate real Y, J, H, K_S filter curves
  2. NB1.18 narrow filter approximation
• 2006-01-31 version 1.1:
  1. Incorporate approx optical reflection data
  2. Incorporate atmospheric absorption model
  3. Improve detector characteristic information
  4. Improved telescope geometry
  5. Various cosmetic tidyups.
• 2006-08-11 version 1.2:
  1. Incorporate full lens-reflectance data - throughput reduced slightly
  2. Substitute square-wave Z-filter place holder with full WFCAM Z transmission. - Z throughput increase
  3. Use purpose-generated atmospheric absorption model - red end throughput increase
  4. Use mirror reflectance data from VISTA Silvering plant - reduced throughput slightly
  5. code overlapping overheads model & include improved readout time - reduce overheads on compound observations
  6. peak of QE curve scaled to more realistic 92%.
• 2009-06-09 version 1.4:
  1. Resurrected Perl version and introduced updated overheads
• 2009-11-30 version 1.5:
  1. Allow for average detector QE in throughput computations
  2. altered Moffat profile for use in aperture corrections to beta=2.5