An Imaging Polarimeter (IMPOL) has been constructed which has a field
of view of about 6.5
for a
1.2 m, f/13 telescope.
An off-axis acquisition and guidance unit capable of using stars as faint
as 
is
also built in the instrument so that long exposures of faint
extended objects like reflection nebulae etc. can be taken while keeping
the image fixed on the CCD face to within one half of a pixel - this stability
of the image is a necessary condition to achieve
a high accuracy in relative photometry between the different
frames used to estimate the polarization.
Observations of nearby standard polarized and unpolarized stars show that
for wideband observations, there is no discernible depolarization and the
instrumental polarization is less than 0.05%. Preliminary results of
wideband polarimetry of stellar fields, using a PSF fitting technique for
determining the centroids of the stellar images and aperture
photometry to derive the intensities of the
individual images, give close to photon-noise limited accuracy of
0.15% for 
stars with about an hour of total exposure
time. For extended objects with brightness about 20th mag per square
arcseconds and a background of
about the same brightness, it is estimated
that an accuracy of about 1%
is possible with 60 minutes
of total exposure time and an aperture of
10 sq arcsec.
Acknowledgements
The project has been funded by the Department of Science and Technology of the Government of India. The authors also wish to thank the Physical Research Laboratory, Ahmedabad for providing telescope time, P.A. Chordia and R. Bedade for their involvement in developing the electronic circuitry for the instrument and M.S. Deshpande for her assistance during its commissioning. Thanks are also due to Dr. A. Saha and an anonymous referee for their valuable comments.