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telescopeimpulssrespons

Telescope impulse response, sometimes written as telescopeimpulssrespons, is a concept in astronomical imaging describing how an optical telescope responds to a brief, localized light input. In practice, the impulse response of an imaging system is represented by its point spread function (PSF), which shows how a point source of light is distributed on the detector.

The PSF is determined by several factors. Diffraction from the telescope aperture imposes a fundamental limit

Measuring and modeling the PSF is essential for data analysis. Astronomers estimate the PSF from observations

In signal-processing terms, the telescope impulse response describes how the true sky image is convolved with

set
by
the
diameter
and
shape
of
the
opening.
Optical
aberrations,
obscurations
by
supports
or
secondary
mirrors,
detector
sampling,
and
atmospheric
turbulence
(for
ground-based
telescopes)
further
shape
the
PSF.
The
ideal,
diffraction-limited
PSF
for
a
circular
unobstructed
aperture
is
the
Airy
pattern;
real
systems
exhibit
diffraction
rings,
asymmetries,
and
wavelength
dependence.
of
bright
stars
or
from
dedicated
calibrations.
The
PSF
can
vary
across
the
field
of
view
and
with
wavelength,
and
may
change
over
time
due
to
atmospheric
conditions
or
instrumental
drift.
Adaptive
optics
and
post-processing
techniques
aim
to
stabilize
or
correct
the
PSF
to
improve
image
quality.
the
PSF
to
produce
the
observed
image.
The
Fourier
transform
of
the
PSF
is
the
optical
transfer
function,
relating
to
contrast
at
different
spatial
frequencies.
Applications
include
PSF
fitting
for
photometry
and
astrometry,
deconvolution
to
sharpen
images,
and
instrument
design
and
calibration.