Changes between Version 8 and Version 9 of GPC1_Bias_Pattern_Study

Timestamp:

Feb 7, 2013, 2:46:36 PM (13 years ago)

Author:

watersc1

Comment:

--

GPC1_Bias_Pattern_Study

@@ -7 +7 @@
 
  2. Applying only the PATTERN.MEDIAN to exposures (without DARK, FLAT, or PATTERN.CONTINUITY) yields a clear x-pixel direction gradient curve.  This is effectively a result of solving for the DARK contribution on a per exposure basis.  Applying DARK + FLAT removes this gradient on OTAs that are well behaved.  This illustrates that the DARK model is not a significant problem for these OTAs.
-[[Image(science_gradient_0.0.png,800px)]]
-[[Image(dark_gradient_0.0.png,800px)]]
-[[Image(science_dark_flat_pattern_0.0.png,800px)]]
+|| Science images, PATTERN.MEDIAN only, OTA56/row 0|| [[Image(science_gradient_0.0.png,400px)]] ||
+|| Dark images, PATTERN.MEDIAN only, OTA56/row 0|| [[Image(dark_gradient_0.0.png,400px)]] ||
+|| Science images, PATTERN.MEDIAN/DARK/FLAT, OTA56/row 0|| [[Image(science_dark_flat_pattern_0.0.png,400px)]] ||
 
- 3. Applying only PATTERN.MEDIAN to a series of bias frames helps explain why the cell-column structures are not well removed by this correction.  The larger scale ripples have a period that is not constrained to a cell.  For example, in the highlighted bias below, I count ~11 ripples in the 4th (from left) column of cells. Whatever is driving these ripples is independent of the cell structure, and as such, these ripples do not reinforce in the PATTERN.MEDIAN calculation. 
+ 3. Applying only PATTERN.MEDIAN to a series of bias frames helps explain why the cell-column structures are not well removed by this correction.  The larger scale ripples have a period that is not constrained to a cell.  For example, in the highlighted bias (OTA31, PATTERN.MEDIAN only) below, I count ~11 ripples in the 4th (from left) column of cells. Whatever is driving these ripples is independent of the cell structure, and as such, these ripples do not reinforce in the PATTERN.MEDIAN calculation. 
 [[Image(column_ripples_in_bias.jpg,1024px)]]
 == February 5, 2013 ==