2.2	Summary of STIS Performance Changes Since 2004

While in most respects the performance of STIS after its repair during SM4 is similar to its performance prior to the 2004 failure, there are some important differences. Most of these changes represent the continuation of previous trends and were anticipated, but still need to be taken into account when planning STIS observations. A few, such as the behavior of the NUV-MAMA dark current, were not expected. Detailed descriptions of these differences are given in the appropriate sections of this document, but for the convenience of users familiar with the previous performance of STIS, we list the most important of these changes, together with references to the appropriate sections of this handbook here:

•	“Changes in CCD Read Noise”

•	“CCD Dark Current”

•	“Charge Transfer Efficiency”

•	“Relative Sensitivity vs. Time for First-Order CCD L-Modes G230LB, G430L, and G750L”

•	“Relative Wavelength-Averaged Sensitivity of STIS MAMA First-Order Low-Resolution Modes G140L and G230L as a Function of Time”

•	“NUV-MAMA Dark Current after SM4”