Why are the Images in Black and White?
cameras on Hubble are equipped with a wide variety
of filters that allow astronomers to investigate
celestial objects as they appear over a broad
range of the electromagnetic spectrum from the
ultraviolet to the infrared. Images are obtained
one filter at a time and each individual image
can be represented in a variety of ways. The
simplest way is to represent the intensity at
each point in the image on a grey scale, i.e.
a black and white image. To make full color
images requires obtaining multiple exposures
of an object through three or more different
color filters. Many objects in the HST archive,
however, have been imaged well in only one filter.
The black and white gallery gives us the chance
to share more of these images with the public.
quality is the critical factor that will guide
us in selecting images for the black and white
gallery. We will include images that have sufficiently
long exposures to minimize noise and that cover
a range of astronomical objects. We are also
interested in images that have aesthetic appeal,
an admittedly subjective quality that is difficult
to define. We hope you will agree, however,
that these new additions to the Hubble Heritage
site open a new and exciting way for us to extend
our vision through Hubble.