Seeing

Sometimes seeing estimates are available, either from the observer at the eyepiece, or from a nearby seeing monitor. It might also be estimated from the core widths of images on CCD frames. Such values should go in a column headed SEEING.

While quantitative measures, such as FWHM in seconds of arc, are most useful, it may still be possible to obtain usable information from seeing expressed on some arbitrary scale. One should be careful not to mix the two types, or to intermix seeing estimated on different scales.