Sky & Telescope - USA (2019-09)

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PHOTO OP AHOY by Greg Redfern

pSKY FROM THE SEA Capturing twilight phenomena, such as the Belt

of Venus (above the shadow of Earth hugging the horizon) and anticre-

puscular rays pointing towards the rising Moon — both seen above — is

easy out to sea where you can view the true horizon.

36 SEPTEMBER 2019 • SKY & TELESCOPE

T

aking an ocean cruise is a popular vacation activity

that’s growing by leaps and bounds. In 2019 alone,

roughly 30 million passengers are expected to embark

on luxury cruise ships worldwide. One thing many of these

cruises have in common is venturing far into the open sea,

where light pollution is minimal or even non-existent — well,

except from the ship itself. On the open ocean you can see

much of the night sky better than at most rural locations, and

you can even capture it in wide-fi eld images.

You may be asking yourself, “Wait, how can you take

astrophotos from a moving ship? Won’t they be blurry?

Aren’t cruise ships all lit up?” All valid questions. An online

search on the subject produces a paucity of information,

with blog posts asking “Can it be done?” and responses often

stating “You can’t because cruise ships are too brightly lit”

or expressing frustration from those who have tried to image

the night sky at sea.

With some effort, it can be done! Eclipses, conjunc-

tions, aurorae, and the zodiacal light are some of the many

astrophotographic possibilities from these giant pleasure

boats, some of which offer astronomically themed tours.

Two ships, Cunard’s Queen Mary 2 and Viking Cruises’

Viking Orion, even have onboard planetariums. The Orion

is also the fi rst cruise ship to have a dedicated astronomer

on staff, while Princess Cruises conducts regular stargazing

sessions. So astronomy is not only welcomed, it is, in many

cases, encouraged.

Cruise Gear

Successful astro-images from a moving ship require a good

camera setup and some knowledge of your “fl oating observa-

tory.” While most any camera can take astropics, your best

bet is to use a DSLR or mirrorless camera (S&T: Apr. 2019, p.

60). These cameras typically operate at high ISO speeds with

acceptable noise levels and accept a wide variety of high-

quality lenses.

I use a Nikon D810a full-frame DSLR (reviewed in S&T:

Feb. 2016, p. 56). It’s designed specifi cally for astrophotog-

raphy, with an extended spectral sensitivity to better record

hydrogen-alpha nebulosity. However, you don’t need a special

Take advantage of dark skies

on your next luxury cruise.

High Seas

Imaging on the