In order to extend the dynamic range of SXT for flare use, the forward
filter wheel is equipped with a stainless steel mesh (``ND'' filter) with a
transmission of 
. While the mesh causes no noticeable
degradation of the image it has been found to scatter X-rays (SXT
Calibration Note 34) at about the 0.7% level. This is a minor effect for
the brightest features in a flare but can provide the dominant signal in
nearby faint features. No adequate means for correcting for this effect
has yet been derived. Therefore, for greatest accuracy it is presently
advisable not to mix images with and without the ND filter in determining
the 
and EM of bright flare features and never to use ND filter images in
the faint features. SXT_TEEM warns the user if the ND filter is included. E.g.,
the light curves, intensity, , and EM of faint areas of ND flare images
may be totally in error. Because the scattering is diffuse and smooth, the
images themselves are quite adequate as pictures of the flares for morphological studies.