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Update the Lenslet Mask Slope

Update the Lenslet Mask Slope

The lenslet mask stage is preloaded with gratity at a 45 deg angle. The slope of the stepping motor travel may change after thermal cycles, leading to incorrect lenslet illumination when we take recmat scans. See https://keckobservatory.atlassian.net/wiki/x/AYCfBg for examples.

To determine the new slope, i.e. scan position vs. stepping motor location, we march the lenslet mask in given step intervals, illuminate the lenslets, and take data.

 

Data

The script to run is /home/osrseng/larkin/scripts/measure_mask_steps, and the syntax is measure_mask_steps 10 (this will take exposures every 10 steps).

 

Data analysis

  1. Compile and run this IDL script /home/osrseng/syeh/RECMAT/mask_steps.pro
    IDL> .comp /home/osrseng/syeh/RECMAT/mask_steps.pro
    % Compiled module: MASK_STEPS.

  2. IDL> mask_steps, dir='230808'

  3. In the pop-up GUI, select any one file from the dataset, except for the first 5 exposures.

  4. In the second pop-up, select the first 5 exposures. These are the darks, and the code will create a master dark file.
    Example: first select s230808_a003022.fits, next select s230808_a003001.fits to s230808_a003005.fits (by pressing shift + down arrow)

  5. The analysis output will be saved to /home/osrseng/syeh/RECMAT/230808/dat

Here is an example of the output analysis, the location of the stepping motor vs. flux of illuminated lenslets. We look for the locations of peak illumination.

location

flux mean

flux stdev

fwhm mean

fwhm stdev

step

median location

-5443

1

1

1

1

 

 

-5443

1

1

1

1

 

 

-5443

1

1

1

1

 

 

-5443

1

1

1

1

 

 

-5443

1

1

1

1

 

 

-5387

1517.48

645.313

50.3816

713.688

 

 

-5376

4690.44

732.389

140.653

505.496

 

 

-5366

18530.3

23160.3

20.3245

709.708

 

 

-5356

124524

222357

2.56803

228.293

1

-5346

-5346

129158

225343

2.55663

359.357

 

 

-5336

123884

225674

2.52299

290.989

 

 

-5326

105820

191481

64.2687

375.174

 

 

-5316

181562

192288

2.51478

411.973

 

 

-5306

368045

393080

2.16993

209.348

2

-5296

-5296

376211

394482

2.46207

386.761

 

 

-5287

366532

392082

2.22596

255.895

 

 

-5276

52284.9

63903.7

3.93793

380.468

 

 

-5266

614617

397696

2.23279

97.0993

3

-5251

-5256

632251

404650

2.2602

79.2104

 

 

-5246

629755

404879

2.2544

40.7607

 

 

-5237

625451

401145

2.27096

30.5194

 

 

-5226

44280.6

22316.7

4.14115

87.5471

 

 

-5216

857328

206967

2.27015

5.96484

4

-5201

-5206

863489

206220

2.26063

3.75333

 

 

-5196

862940

205334

2.26356

4.51102

 

 

-5186

855079

200073

2.27042

6.24375

 

 

-5176

74705

20191.2

4.55509

3.65968

 

 

-5166

918580

156720

2.23562

4.80443

5

-5151

-5156

920776

157927

2.22665

3.06446

 

 

-5146

925012

157148

2.24961

6.65813

 

 

-5137

861077

158174

2.21586

0.297405

 

 

-5126

460175

175706

2.51891

4.69936

 

 

-5116

918448

156745

2.21999

4.75987

6

-5106

-5106

919978

157108

2.20973

5.21683

 

 

-5096

915463

156308

2.2094

5.16279

 

 

-5086

165129

140815

3.39556

1.94601

 

 

-5076

907510

188279

2.23926

5.56845

7

-5061

-5066

914993

190373

2.24783

5.09505

 

 

-5056

912784

190373

2.2416

4.6697

 

 

-5046

896547

191216

2.26154

6.12843

 

 

-5037

86905.4

28716.3

4.59728

78.2796

 

 

-5026

926340

155266

2.23314

6.48522

8

-5011

-5016

931052

155862

2.2408

6.43884

 

 

-5006

927134

155457

2.23606

5.48261

 

 

-4996

821191

182377

2.22083

15.5321

 

 

-4987

590132

183972

2.41833

26.1635