If you already have a Seekey, you may try this out on
the illustration of lanterns above.
Arrange the filters side by side. Hold the Seekey close to your eye, or
in front of your binoculars, and close the other eye. Move the Seekey in order to look alternately through the red and the green filter.
Red is only visible through the red filter.
Green is only visible through the green filter.
White is on the other hand visible through both the red and the green
To detect buoys and marks at a distance
Arrange the filters side by side. Move the Seekey rather fast in order
to alternately look through the red and the green filter over and over
Different coloured things will now appear to have a twinkling effect and
will be easy to find. This works best with red things in blue or green
surroundings. Even a person with a normal colour vision will have an advantage
using the Seekey at long distances or in hazy weather.
See more on the chart
A great deal of the safety information is printed in red. The "twinkling effect" method works very well also in this case.
Much of the information in the charts is printed with thin lines and small symbols. In this case it is especially difficult to tell the colours apart without the Seekey.
You may see our special instructions for your navigation by clicking here
Dutsch instructions for your navigation
Also available in swedish
Some maritime links
The Swedish Sea Rescue Society
The Swedish Lighthouse Society
Briggen Tre Kronor
Identify navigational lights in surroundings with other
disturbing lights, e. g. from ashore
Fixed lights and leading lines you will find using the filter with the
colour opposite to the light you are looking for. Alternatively look alternately
through the filters, as described above.
Often it is difficult to detect other ships against a background disturbed
by other lights. E. g. when approaching a harbour or in fairways close
to populated areas. At such occasions the Seekey is very useful as you
often and regularly check for approaching green or red lanterns.
The different red-green colour vision is also called colour blindness or colour deficiency.
Comments from Seekey customers
- I want to take the opportunity to tell that the Seekey works well for my sailing friend who has a colour problem. The red buoys turn obvious and the method of elimination does the rest.
Eva Nordström, Editor.
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…as soon as I opened the packet I put it to the test around the house, and I was amazed with the results. It was rather like wearing a pair of spectacles for the first time and seeing the world un-blurred!...
…took it along to Dover harbour, close to my house, one night. Amazing! Port control lights and buoys, previously with the colour indistinguishable to me at a distance, lept out and were obvious! I can't wait to take the Seekey sailing…