One of the most basic types of astrophotography and yet equally stunning is that involving star trails, particularly
around the celestial poles or immediately due east or west. In addition to capturing the motion of stars around the
north pole which are circumpolar and, hence, never rise or set, we also have the ability to capture seasonal
constellations and stars in such photos, thus allowing for different opportunities during different seasons. Star trail
photos also provide direct evidence that our planet rotates and does so at a rate of 15° per hour. Furthermore, by
studying the arc for a particular star, especially as far away from the pole as possible, one can indirectly estimate
the length of the (total) exposure which often ranges from seven to eight hours in duration and is totally dependent
on the end of astronomical twilight one evening and its onset
the following morning.
Many star photos are centered on Polaris, a double star system which represents our quickest means to locating the
north celestial pole, for it lies less than 1.0° from it, and is an excellent starting point for the polar alignment
of a telescope (and finding your way home if you are lost!). Due to the extended length of the typical exposures
involved, the best film for such work is Kodak Elite Chrome (ISO 100) whose reciprocity failure is nearly zero or
Fujichrome Velvia and Provia (ISO 50 and 100) emulsions with equally impressive curves! With respect to equipment, it
is rudimentary, for a camera with extended exposure capibility is required along with a firm tripod and shutter
release and locking cable. It is also preferable that the camera used have a mechanical shutter so that battery
consumption and power does not become an issue during mid-exposure. The final requirement is a location with dark
skies - the darker the better so that the trails and their colouration will be as bright and contrasty as possible -
with, preferably, an interesting foreground which can be used to enrich the final result.
Note: With a coastline which measures 13,676 kilometers, Greece has the largest coastline
in Europe and the eleventh largest in the world. As a result, the number of shipwrecks above and below sea level which
characterize the extended greek coastline and waters should come as no surprise.
The shipwreck below involves the general cargo ship "Dimitrios" which finally run aground at its current location on
December 23rd, 1981 roughly 3.8 kilometers northeast of Gytheio and on the sandy beach of Valtaki in southern Greece.
The ship was originally docked at the port of Gytheio following unexpected and serious health problems involving its
captain but a variety of problems with the unpaid crew and the insurance company thereafter led to its eventual
confiscation by port authorities. Consequent mechanical problems and the influx of water into the ship's hull led to
port authorities deeming the ship unsafe and who requested that it be transported to open waters. Following two
heavy storms while in open waters, the cargo ship finally reached its current location and where it has remained since
late 1981.
Built in Denmark in 1950 and originally named Cornilia, the cargo ship measures 66.71 meters in length and 10.09 meters
in width and had a gross tonnage of 965 tons. The cargo vessel was later renamed Klintholm and finally Dimitrios.
Note: For additional results involving the Sun, Moon and other celestial bodies rising or setting
against well-known monuments and sites from around the world, please click
here.
Proper Star Name: Polaris Bayer Letter: á Ursae Minoris Tycho Catalog: TYC 4628-237-1 SAO Catalog: SAO 308 Luminosity 2290 +/- 282 x Sun Distance: 431 +/- 26 light yrs RA / Dec: 02h 39m 31s / +89° 17' 39" B-V Color Index: +0.570 mag Magnitude: 1.98 |
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Date: July 28-29, 2017 22:20 - 04:35 UT+3 Location: Valtaki Beach, Gytheio, Greece Equipment: Canon EOS 6D Baader BCF2 Filter Canon EOS EF 28mm/f1.8 USM @ f3.5 Exposures: 375 min (186 x 120 sec) (RGB) 012 min (006 x 120 sec) (Dark) ISO 1000 JPG Fine Image Format 5472x3648 Image Size Custom White Balance Manual Mode Continuous Servo Mode Software: Startrails V2.3 Photoshop CS5 Processing: Dark Frame Reduction Layers and Lighten Resampling Unsharp Masking JPG Compression |