# The following file is from Jim Gunn, from June 2001.  It should be
# self-explanatory; for most purposes, you will want to use the second
# column.  Consider this file preliminary. 
# 
#   These filter curves have been used to calculate the effective
# wavelengths and the qtdl/l (see Chapter 8 of the Black Book) of the
# filters; the values are:
# 
# u 3551 0.0171 
# g 4686 0.0893 
# r 6166 0.0886 
# i 7480 0.0591 
# z 8932 0.0099 
# 
# Table Caption For Response Functions
# 
# The first column is the wavelength in \AAngstroms.  The second column
# (respt) is the quantum efficiency on the sky looking through 1.3
# airmasses at APO for a point source.  The third column (resbig) is the
# QE under these conditions for very large sources (size greater than
# about 80 pixels) for which the infrared scattering is negligible.  The
# only filters for which the infrared scattering has any effect are r and
# i; the scattering in the bluer chips is negligible, and the z chips are
# not thinned and the phenomenon does not exist.  The fourth column
# (resnoa) is the response of the third column with {\it no} atmosphere,
# and the fifth column is the assumed atmospheric transparency at {\it
# one} airmass at APO.  The tables were constructed using monochromator
# illumination of the camera with a bandpass of about 100 \AA, sampled for
# the u filter at 50 \AA intervals and for the others at 100 \AA
# intervals.  These measurements were compared with measured responses of
# the component filters and detectors and three additional points were
# interpolated using these data, two at the extreme toes and one
# additional (in g, r, and i) at the point of the beginning of the sharp
# cutoff of the shortpass interference filter.  These points are necessary
# in order to make spline interpolation of the response data well-behaved.
# These spline-interpolated response data were then multiplied by measured
# aluminum reflectivities and scaled atmospheric transmission to produce
# the tables below. The overall normalization is somewhat uncertain,
# but this uncertainty does not affect the shapes. Note, however, that
# there has been no attempt to remove the finite resolution of the
# monochromator measurements. These tables are the {\it averages} of the
# responses for all six of the camera chips with a given filter. The
# responses are in general very similar except in the z band, where the
# nonuniformity of the infrared rolloff, presumably associated with 
# varying thickness of the epitaxial layer or perhaps the gate structures
# in these thick devices, introduces variations in the effective wavelengths
# of the filters of order 100 \AA. We are currently working on better
# response functions and will present them when they become available, but
# these will suffice for most applications. In all cases the first point
# is a measured point, so the grid of wavelengths at which measurements
# exist is a subset of the wavelength lists here.
# 
#  SDSS Camera i Response Function 89  Points
#
#   lam    respt   resbig   resnoa   xatm

  6430   0.0000   0.0000   0.0000   0.9346
  6455   0.0001   0.0001   0.0001   0.9354
  6480   0.0003   0.0003   0.0003   0.9363
  6505   0.0004   0.0004   0.0004   0.9373
  6530   0.0004   0.0004   0.0005   0.9385
  6555   0.0003   0.0004   0.0004   0.9395
  6580   0.0003   0.0003   0.0003   0.9400
  6605   0.0004   0.0004   0.0005   0.9398
  6630   0.0009   0.0009   0.0010   0.9386
  6655   0.0019   0.0019   0.0021   0.9366
  6680   0.0034   0.0034   0.0036   0.9349
  6705   0.0056   0.0056   0.0060   0.9345
  6730   0.0103   0.0104   0.0111   0.9366
  6755   0.0194   0.0197   0.0208   0.9421
  6780   0.0344   0.0349   0.0366   0.9492
  6805   0.0561   0.0569   0.0597   0.9494
  6830   0.0839   0.0851   0.0913   0.9334
  6855   0.1164   0.1181   0.1317   0.9057
  6880   0.1528   0.1552   0.1779   0.8862
  6905   0.1948   0.1980   0.2260   0.8893
  6930   0.2408   0.2448   0.2719   0.9083
  6955   0.2857   0.2906   0.3125   0.9311
  6980   0.3233   0.3290   0.3470   0.9450
  7005   0.3503   0.3566   0.3755   0.9464
  7030   0.3759   0.3829   0.3978   0.9561
  7055   0.3990   0.4067   0.4142   0.9709
  7080   0.4162   0.4245   0.4256   0.9826
  7105   0.4233   0.4320   0.4331   0.9827
  7130   0.4165   0.4252   0.4377   0.9629
  7155   0.3943   0.4028   0.4405   0.9192
  7180   0.3760   0.3844   0.4416   0.8849
  7205   0.3823   0.3911   0.4411   0.8974
  7230   0.3918   0.4011   0.4392   0.9182
  7255   0.3892   0.3988   0.4358   0.9195
  7280   0.3828   0.3924   0.4315   0.9153
  7305   0.3820   0.3919   0.4265   0.9225
  7330   0.3884   0.3988   0.4214   0.9436
  7355   0.3872   0.3979   0.4165   0.9505
  7380   0.3821   0.3930   0.4119   0.9496
  7405   0.3787   0.3898   0.4077   0.9512
  7430   0.3759   0.3872   0.4039   0.9531
  7455   0.3727   0.3842   0.4006   0.9535
  7480   0.3681   0.3799   0.3975   0.9508
  7505   0.3618   0.3737   0.3943   0.9449
  7530   0.3565   0.3685   0.3906   0.9416
  7555   0.3554   0.3678   0.3862   0.9483
  7580   0.3478   0.3603   0.3812   0.9429
  7605   0.1473   0.1527   0.3757   0.4926
  7630   0.2096   0.2176   0.3700   0.6546
  7655   0.2648   0.2752   0.3641   0.7939
  7680   0.3300   0.3434   0.3583   0.9530
  7705   0.3256   0.3392   0.3526   0.9558
  7730   0.3223   0.3361   0.3473   0.9602
  7755   0.3179   0.3319   0.3424   0.9615
  7780   0.3129   0.3272   0.3379   0.9605
  7805   0.3077   0.3221   0.3337   0.9583
  7830   0.3026   0.3173   0.3297   0.9559
  7855   0.2980   0.3129   0.3259   0.9541
  7880   0.2944   0.3095   0.3224   0.9541
  7905   0.2921   0.3077   0.3194   0.9567
  7930   0.2916   0.3075   0.3169   0.9622
  7955   0.2921   0.3086   0.3150   0.9692
  7980   0.2927   0.3098   0.3132   0.9762
  8005   0.2923   0.3098   0.3111   0.9814
  8030   0.2896   0.3076   0.3081   0.9833
  8055   0.2840   0.3021   0.3039   0.9801
  8080   0.2758   0.2939   0.2996   0.9702
  8105   0.2642   0.2821   0.2945   0.9524
  8130   0.2427   0.2597   0.2803   0.9285
  8155   0.2091   0.2242   0.2493   0.9075
  8180   0.1689   0.1815   0.2060   0.8931
  8205   0.1276   0.1374   0.1578   0.8853
  8230   0.0901   0.0973   0.1118   0.8843
  8255   0.0603   0.0652   0.0743   0.8902
  8280   0.0378   0.0410   0.0458   0.9033
  8305   0.0218   0.0237   0.0257   0.9242
  8330   0.0117   0.0128   0.0134   0.9483
  8355   0.0068   0.0074   0.0077   0.9591
  8380   0.0048   0.0053   0.0055   0.9576
  8405   0.0033   0.0036   0.0037   0.9567
  8430   0.0020   0.0022   0.0023   0.9564
  8455   0.0013   0.0014   0.0015   0.9565
  8480   0.0010   0.0011   0.0011   0.9569
  8505   0.0009   0.0010   0.0011   0.9576
  8530   0.0009   0.0010   0.0011   0.9584
  8555   0.0008   0.0009   0.0009   0.9592
  8580   0.0005   0.0006   0.0006   0.9598
  8605   0.0002   0.0003   0.0003   0.9602
  8630   0.0000   0.0000   0.0000   0.9603
