One of the most important problems that still exist in AERONET is the well-known higher AOD uncertainties in the ultraviolet (UV) Cimel spectral bands due to higher extinction, temperature dependence, and tracking problems in this spectral range. Izaña will host a new Cimel CE318-T instrument developed by AERONET NASA at GSFC (Goddard Space Flight Center) headquarters to try to deep into these problems. This prototype, called NEON, has all its filter positions occupied by 340 filters. Some testing will be performed at Izaña to check the effect of pointing delay on the AOD at 340 nm.