Pixel Scale (PSCALE) is in arc seconds.
The value can be entered in of three ways:
May be entered as a string or any numeric type for equality matching
May be a string of the format ‘(min) - (max)’ for range matching
May be a string of the form ‘(operator) (number)’ where operator is one of: lt gt le ge < > <= >=
Currently only implemented for SDO, which is 0.6 arcsec per pixel at full resolution for AIA.
Documentation in SSWIDL routine vso_search.pro.