I. Bias Frames

• Problem: There is 2D structure in the bias frames which is not fully accounted for by the overscan region
• Solution: Take 10 exposures per binning setup
• Alternate Solution: Use an archived bias frame [known to be ok]

II. Flats

• Problem: There is significant scattered light with the internal flats
• Solution: Take >5 dome flats per slit width (note this is time consuming)
• Alternate Solution: Use an archived flat [not well tested]

III. Arcs

• Problem: All of the lamps are needed to get a solution across the entire wavelength range
• Problem: There isn't a lot of signal in some important CuAr lines
• Solution: Take exposures with all lamps on (start with all on and turn of Hg,Xe)
• Solution: Take multiple arc exposures (5 ideally per slit width)
• Alternate Solution: Use an archived arc [not well tested]

IV. Order Curvature

• Issue: The orders are significantly curved in the data images
• Solution: Take exposures with the multi-holes slit
• Problem: Tough to get sufficient flux in cornes of the CCD
• Solution: Take several exposures during twilight
• Alternate Solution: Use an archived map [works well]