Accuracy Of Mechanical Watches - Seiko 8L35 Instructions

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LUMIBRITE
LumiBrite is a luminous paint that is completely harmless to human beings and the natural
environment, containing no noxious materials such as radioactive substances.
LumiBrite is a newly-developed luminous paint that absorbs the light energy of sunlight or
artificial light in a short time and stores it to emit light in the dark.
For example, if exposed to a light of more than 500 lux for approximately 10 minutes, LumiBrite
can emit light for 5 to 8 hours.
Please note, however, that, as LumiBrite emits the light it stores, the luminance level of the
light decreases gradually over time. The duration of the emitted light may also differ slightly
depending on such factors as the brightness of the place where the watch is exposed to light
and the distance from the light source to the watch.
When you make a dive in dark water, LumiBrite may not emit light unless it has absorbed and
stored light sufficiently.
Before diving, therefore, be sure to expose the watch to light under the conditions specified
above, so that it fully absorbs and stores light energy. Otherwise, use the watch together with
an underwater flashlight.
< Reference data on luminance >
(A) Sunlight
[Fine weather]: 100,000 lux
(B) Indoor (Window side during daytime)
[Fine weather]: more than 3,000 lux
[Rainy weather]: less than 1,000 lux
(C) Lighting apparatus (40-watt daylight fluorescent light)
[Distance to the watch: 1 m]: 1,000 lux
[Distance to the watch: 3 m]: 500 lux (average room luminance)
[Distance to the watch: 4 m]: 250 lux
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[Cloudy weather]: 10,000 lux
[Cloudy weather]: 1,000 to 3,000 lux
* " LUMIBRITE " is a trademark of SEIKO HOLDINGS CORPORATION.

ACCURACY OF MECHANICAL WATCHES

The accuracy of mechanical watches is indicated by the daily rates of one week
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or so.
The accuracy of mechanical watches may not fall within the specified range
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of time accuracy because of loss/gain changes due to the conditions of use,
such as the length of time during which the watch is worn on the wrist, arm
movement, whether the mainspring is wound up fully or not, etc.
The key components in mechanical watches are made of metals which expand
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or contract depending on temperatures due to metal properties. This exerts an
effect on the accuracy of the watches. Mechanical watches tend to lose time at
high temperatures while they tend to gain time at low temperatures.
In order to improve accuracy, it is important to regularly supply energy to
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the balance that controls the speed of the gears. The driving force of the
mainspring that powers mechanical watches varies between when it is fully
wound and immediately before it is unwound. As the mainspring unwinds, the
force weakens.
Relatively steady accuracy can be obtained by wearing the watch on the wrist
frequently for the self-winding type and winding up the mainspring fully
everyday at a fixed time to move it regularly for the wind-up mechanical type.
When affected by external strong magnetism, a mechanical watch may loss/
l
gain time temporarily. The par ts of the watch may become magnetized
depending on the extent of the effect. In such a case, consult the retailer from
whom the watch was purchased since the watch requires repair, including
demagnetizing.
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