20020715: SSEC, CSU 4 km visible calibration (cont.)

>From: Darren Gallant <address@hidden>
>Organization: UCAR/JOSS
>Keywords: 200207111918.g6BJIGa29261 McIDAS AREA calibation

Darren,

re: If there is no noise in the image, space would produce zero counts
the sensor.  This will translate to zero brightness, zero albedo, etc.

>So, this correction is made when the image is ingested and an areafile is
>created.

I am not certain about what you mean by "correction".  If the sensor were
perfect, the number of counts would be zero and everything from that point
on that is a function of the counts (like brightness, albedo, etc.) would
also be zero.

>I'm a little confused here.

I am confused about your question because I don't really understand what
you are trying to accomplish.

In the more real case of sensor counts never being zero, values less
than some point might be interpreted as noise. I suppose that one could
set the brightness values to zero, but I don't believe that McIDAS
satellite ingesters do that.  I think that they will interpret the data
as being some valid value leaving it up to the user to remember that
the instrument is not perfect.

>Are there references to this process?

Not that I know of.

>I want to replicate this procedure and test the results.

Replicate which procedure?

Tom