XRT Stray Light Study 3 -- Measurement and Correction.

Link to the 2nd test page.
Link to the 4th test page.

(29 May, 2014 by Aki Takeda)

1. Stray light correction project -- the 3rd test.

1.1 Purposes of the 3rd test.

1.2 Test sequence.

The second test was performed on 27-May-2014, 20:25 -- 20:50UT.

2. Result of the test observation.

2.1 Solar condition


2.2 Sunset light curves

Light curve from the 1st and 2nd tests

2.3 Stray light images

Al-poly stray light images obtained (movie).

No significant stray light detected.

C-poly stray light images obtained (movie).

2.4 Image correction.

Correction of the synoptic composite image (C-poly) taken 16 minutes before the 3rd test.

BEFORE [synoptic (double) composite image] AFTER [stray light image (prep-ed) subtracted]
[memo] Synoptic Composite Image Archive : 
1) the May-2014 page updated with corrected Ti-poly images. 
2) Ti-poly images in the Apr-2014 page also re-processed for correction with
   the same terminator image taken on 20140515.
3) Ti-poly (1024x1024) images in the May-2012 page (the stray-light problem
   started this month), are tried to correct, using the 20140515 terminator 
   image. It turned out that simple subtraction causes over-correction. 
   A fudge factor of 0.5 is effective to get desent Ti-poly images.