Old Rotation PA -> Encoder Table for IGRINS

Old Rotation PA -> Encoder Table for IGRINS

For a detailed Finder Chart and rotation setting see Kyle Kaplan's software. For rough rotations use the lookup table below.

363 = Default Encoder Setting at 90 deg. PA (slit east to west)  (NOTE: Default encoder setting was 393, but changed to 363 after installation of rotator)

Position Angle (Start north and go east, N=0, E=90, S=180, W=270 degrees, Default = 90 deg slit oriented east-west)

(Encoder Setting) = 363 - 90 + (Position Angle) = 273 + (Position Angle)

WARNING: We recommend you do not rotate the instrument +/- 90 degrees from the nominal 90 degree position to avoid entangling wires and hoses.  The encoder setting limits are:

Positon Angle

Encoder Setting

Positon Angle

Encoder Setting

285

198

300

213

315

228

330

243

345

258

360, 0

273

15

288

30

303

45

318

60

333

75

348

90 (default)

363 (default)

105

378

120

393

135

408

150

423

165

438

180

453

195

468

210

483

225

498

240

513

255

528

270

543