TRICK 101

This is an FAQ page for using TRICK, from observers' perspectives.

Can I use TRICK in the LGS mode?

Yes, TRICK can improve the performance in LGS mode when a a suitable IR guide star available.

What performance gains can I expect when a suitable IR TT star is within the TRICK usable field?

Can I use TRICK in the NGS mode?

Technically, it’s possible to use TRICK in NGS mode but NGS mode’s only purpose is for engineering and TRICK science capabilities are limited to LGS mode only.

How should I prepare LGS starlists for TRICK?

Use the same AO guide star tool at https://www2.keck.hawaii.edu/software/findChartV2/index.php.

What is the faintest IR tip tilt star I can use for TRICK?

14- 15 mag in H or K band. TRICK doesn’t go as faint as STRAP.

Do I still need an optical tip tilt star?

Yes, you still need an R band tip tilt star for target acquisition and LBWFS corrections.

How big is the TRICK detector field of view and what is the pixel scale?

The detector field of view is 102”x102” with a 50 mas pixel scale.

What is the usable field of view ?

How far off axis (offset from science target) can the IR TT star be located?

Can I dither? Can I switch from OSPEC to OIMAGE?

What IR science wavelengths are avaiable?

Can I change science the filter bandpass from K to H, K to J, etc.?

Do I need to identify IR TT star during pre-observing planning or can the star be identified in real time?

Does the IR TT need to be a point source?

Does TRICK perform well in poor seeing (1-2” Vband natural seeing)?

What is the overhead to acquire targets and close loops in TRICK?

In general, the overhead is about twice that of using optical tip tilt (STRAP) only.