The GMOS Nod & Shuffle mode applies techniques adopted for the infrared to optical MOS, long-slit, and IFU (Gemini-South only) spectroscopy whereby the sky is sampled with the same pixels used to observe the science target.

The advantages of observing with Nod & Shuffle include:

• Improved sky subtraction
• Potential increased density of slits

Disadvantages of observing with Nod & Shuffle include:

• Increased observing overheads
• Potential decreased field of view

Further details about Nod & Shuffle mode provided in this section are as follows.

• Basic concepts
• Band and micro shuffling
• Nodding
• Defining a Nod & Shuffle Observation
• Performance
• Focal plane masks
• Commissioning team