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Setup for LED dome flats

R. Boyle & E. Green

No need / better NOT have the telescope running (no oil system in basement) But TCS must be running to see telescope ALT, AZ, and DOME AZ readout.
Telescope points to white square in dome at DOME AZ=351°, and telescope fixed AZ=180° (same as stow), manually bring Alt to 30°

After finishing your flats, return dome to home AZ 180°:
- In DOME Tracking subwindow: click on “manual” to switch to “tracking” and dome automatically returns almost to home. Close the subwindow, and cycle Dome Tracking off/on a few times to bring it to true home of AZ=l80°.

Before taking flats, tilt the telescope in ALT manually so that it points at the screen:
- In mount control, click “open mirror cover.”
- Send co-observer to the dome while observer sits at TCS terminal.
- Observer: click “brake off” while co-observer is standing next to the telescope. (If telescope starts to fall down in ALT independently, co-observer should tel1 observer to put brake back on.)
- Co-observer: pull telescope down by muscle power, making sure to pull on the mirror cell or something robust and not on an instrument or anything delicate, while observer is watching and communicating the altitude; when telescope is stopped at ALT=30°, observer should click brake back on.

After finishing your flats, return Telescope ALT to 90° by reversing how you put it to 30°:
- Co-observer in dome ready to push up, after observer at console releases brake, and tells when ALT=90°. Then brake on, stow pins in. Close mirror cover.

in control room, on terminal running AZCAM:
open Internet Explorer,
click on “new tab”
click on star (favorites)
click on “Vatt flatfield LED GUI” this opens GUI with all the lamps OFF. So to turn on lamps, click on boxes or on sliders to select percent illumination
make test flats to your satisfaction. Keep exposure times above about 4 or 5 seconds to avoid shutter-effect dependence
when finished flats, click lamps off, then close IE browser