  $\eta$ Tel is an 18 Myr system with a 2.09 M$_{\odot}$ A-type star and an
M7-M8 brown dwarf companion, $\eta$ Tel B, separated by 4.2'' (208 au).
High-contrast imaging campaigns over 20 years have enabled orbital and
photometric characterization. $\eta$ Tel B, bright and on a wide orbit, is
ideal for detailed examination.
  We analyzed three new SPHERE/IRDIS coronagraphic observations to explore
$\eta$ Tel B's orbital parameters, contrast, and surroundings, aiming to detect
a circumplanetary disk or close companion. Reduced IRDIS data achieved a
contrast of 1.0$\times 10^{-5}$, enabling astrometric measurements with
uncertainties of 4 mas in separation and 0.2 degrees in position angle, the
smallest so far.
  With a contrast of 6.8 magnitudes in the H band, $\eta$ Tel B's separation
and position angle were measured as 4.218'' and 167.3 degrees, respectively.
Orbital analysis using Orvara code, considering Gaia-Hipparcos acceleration,
revealed a low eccentric orbit (e $\sim$ 0.34), inclination of 81.9 degrees,
and semi-major axis of 218 au. $\eta$ Tel B's mass was determined to be 48
\MJup, consistent with previous calculations.
  No significant residual indicating a satellite or disk around $\eta$ Tel B
was detected. Detection limits ruled out massive objects around $\eta$ Tel B
with masses down to 1.6 \MJup at a separation of 33 au.
