54 ASTRONOMY • APRIL 2018
a remote trigger or intervalometer to open
your camera’s shutter so you don’t have to
touch the camera.The burning question
And now, the answer to the question that’s
been on your mind, and the one I get asked
everywhere I go: What settings do I use to
take a nightscape?
To answer that question, we must ask
another one first: What kind of nightscape
will you be shooting? For brevity, I’m going
to focus on the most basic nightscape, a
single exposure. Stacked images, pan-
oramic, and long-focal-length nightscapes
involve another level of technical complex-
ity around topics like image registration,masking, nodal points, paral-
lax, stitching, and tracking
hardware. It would take quite a
few more pages to cover them
all adequately.
Earlier, I talked about the
trade-offs in nightscapes
between image quality and
light gathering. When decid-
ing on your camera settings,
this is where the rubber meets
the road. If you want lower noise (less
grainy images), use a lower ISO value.
Unfortunately, this comes at the expense of
light gathering.
If you want better details, especially
sharper stars at the edges of your images(less coma), close down your lens a few
f-stops from wide open. But again, this
comes at the expense of light gathering.
Likewise, if you want more pinpoint stars
across your entire field of view, you must
shorten your shutter speed.These two images illustrate leading lines. The one above shows
a meandering leading line, while at right is a vertical one.