• 01/07/00
• 08/30/99
• 10/20/99
• Hot Pixels in FI Devices - Postscript file - Mike Pivovaroff 9/20/99

The details follow:

Making a bad pixel/bad column list:

[1] Look at Maxim's images by eye and flag bad columns and pixels, grading the columns strong/weak/very weak/node boundary/flight.

[2] make histograms vs. chipx and list columns greater than + 2 sigma. This is the mk_chipx_histo.csh script. Compare in detail. Also compare to Bev's criticisms. Edit list by hand (this procedure doesn't do very well at limited chipy extents, for instance).

[2a] Get everyone to agree on the list (Maxim, Bev, cc: Mark Bautz).

[3] Glenn asked for 1-1024 in chipy instead of 2-1023 as Maxim had.

[4] Turns out the tool adds padding around bad pixels/columns, so remove that from the list. Also add a flag field so I can remember what's going on, include everything, and then strip out only the real bad columns to send to Glenn.

[5] extract using

row < badpix_C_200922_full.rdb Note eq W or Note eq S or Note eq BP

for Glenn. Note column is S (strong) W (weak) VW (very weak), F (Flight), FB (Flight boundary), NB (Node boundary), or BP (bad pixel). This gives only the bad columns (strong or weak) and bad pixels, and no node boundaries and no next-to-bad columns.

The list of flight software excluded bad pixels is then added to this file, called badpix_C_200922.rdb.

Following is the file delivered to SDS/Glenn Allen for generation of the CALDB entry.

* Note: CHIPX0, CHIPX1, CHIPY0, and CHIPY1 are the boundaries of a rectangle defining a region of bad pixels. For a single pixel, CHIPX0=CHIPX1 and CHIPY0=CHIPY1

Bad Pixels Table
CCD ID	Type	Position	Note	CHIPX0	CHIPX1	CHIPY0	CHIPY1
0	FI	I0	F	71	73	1	1024
0	FI	I0	W	79	79	1	1024
0	FI	I0	S	81	81	1	1024
0	FI	I0	S	95	95	1	1024
0	FI	I0	W	165	165	1	1024
0	FI	I0	W	226	226	1	1024
0	FI	I0	W	484	484	1	1024
0	FI	I0	W	580	580	1	1024
0	FI	I0	S	1010	1010	1	1024
0	FI	I0	S	1015	1015	1	1024
0	FI	I0	BP	303	303	253	253
1	FI	I1	W	54	54	1	1024
1	FI	I1	W	97	97	1	1024
1	FI	I1	F	303	303	1	1024
1	FI	I1	F	409	409	1	1024
1	FI	I1	W	521	521	1	1024
1	FI	I1	W	558	558	1	1024
1	FI	I1	W	583	583	1	1024
1	FI	I1	W	691	691	1	1024
1	FI	I1	W	704	704	1	1024
1	FI	I1	S	1008	1008	1	1024
1	FI	I1	BP	533	533	33	33
2	FI	I2	W	23	23	1	1024
2	FI	I2	W	127	127	1	1024
2	FI	I2	S	134	134	1	1024
2	FI	I2	W	162	162	1	1024
2	FI	I2	W	437	437	1	1024
2	FI	I2	W	548	548	1	1024
2	FI	I2	S	559	559	1	1024
2	FI	I2	W	570	572	1	1024
2	FI	I2	W	671	671	1	1024
2	FI	I2	W	699	699	1	1024
2	FI	I2	W	818	818	1	1024
2	FI	I2	W	930	930	1	1024
2	FI	I2	S	1018	1018	1	1024
3	FI	I3	W	474	474	1	1024
3	FI	I3	W	492	492	1	1024
4	BI	S0	W	9	9	1	1024
4	BI	S0	S	39	39	1	1024
4	BI	S0	S	107	107	1	1024
4	BI	S0	W	162	162	1	1024
4	BI	S0	S	197	197	1	1024
4	BI	S0	S	363	363	1	1024
4	BI	S0	S	488	488	1	1024
4	BI	S0	S	507	507	1	1024
4	BI	S0	W	544	544	1	1024
4	BI	S0	S	586	586	1	1024
4	BI	S0	W	601	601	1	1024
4	BI	S0	S	628	628	1	1024
4	BI	S0	W	839	839	1	1024
4	BI	S0	S	862	862	1	1024
4	BI	S0	S	876	876	1	1024
4	BI	S0	W	890	890	1	1024
4	BI	S0	S	956	956	1	1024
4	BI	S0	S	968	968	1	1024
5	FI	S1	S	233	233	313	322
5	FI	S1	S	233	251	313	313
5	FI	S1	S	671	671	1	1024
5	FI	S1	BP	161	161	206	206
5	FI	S1	BP	226	226	564	564
5	FI	S1	BP	341	341	427	427
5	FI	S1	BP	367	367	497	497
5	FI	S1	BP	607	607	281	281
5	FI	S1	BP	716	716	718	718
5	FI	S1	BP	1022	1023	166	167
5	FI	S1	F	383	383	585	585
5	FI	S1	F	792	792	351	351
6	FI	S2	S	58	58	1	1024
6	FI	S2	S	585	585	1	1024
6	FI	S2	W	683	683	1	1024
6	FI	S2	W	1003	1003	1	1024
7	BI	S3	F	496	498	441	1024
7	BI	S3	S	497	497	1	40
7	BI	S3	W	738	738	973	1024
8	FI	S4	W	2	2	1	1024
8	FI	S4	W	5	5	1	1024
8	FI	S4	W	20	20	1	1024
8	FI	S4	W	25	25	1	1024
8	FI	S4	S	33	33	1	1024
8	FI	S4	W	453	453	1	1024
8	FI	S4	W	514	514	1	1024
8	FI	S4	W	516	516	1	1024
8	FI	S4	S	541	541	1	1024
8	FI	S4	W	632	632	1	1024
8	FI	S4	W	876	876	1	1024
8	FI	S4	W	910	910	1	1024
8	FI	S4	S	952	952	1	1024
8	FI	S4	W	966	966	1	1024
8	FI	S4	W	1007	1007	1	1024
8	FI	S4	BP	603	603	23	23
9	FI	S5	W	93	93	1	1024
9	FI	S5	W	328	328	1	1024
9	FI	S5	S	409	409	1	1024
9	FI	S5	W	962	962	1	1024

Thanks to Bev LaMarr, Maxim Markevitch, and Mark Bautz for their help and advice.

Last modified: 11/15/10

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