Comparison Seiko SPB383J1 vs Seiko SPB221J1

A device primarily used in mechanical watches that provides continuous winding of the watch by moving the wearer's hand. Most often, it is made in the form of a rather massive plate in the form of a sector, which is fixed with a narrow end on an axis in the centre of the mechanism. When the hand and the watch attached to it oscillate — for example, while walking — the plate rotates, providing a spring winding.

One of the advantages of self-winding watches is obvious: they do not need to be wound as often as classic mechanical ones, and if worn constantly, they can do without manual winding at all. The course of such watches is more uniform, since the spring is constantly in an almost compressed state — this has a positive effect on accuracy. Also , automatic winding in mechanical watches is useful for waterproof models, in which the crown is attached to the thread during non-working hours, sealing the case — since the thread does not have to be used often, it wears out less, which has a positive effect on reliability. On the other hand, the self-winding plate increases the weight and thickness of the case, as well as the cost of the watch. In addition, the use of this function in miniature female models is associated with a number of difficulties, and if the owner leads a sedentary lifestyle (for example, due to old age), all the advantages of self-winding come to naught.

Note that there a...re also self-winding quartz watches — these are models with Kinetic technology. For more information about them, see "The source of the move."

The number of stones provided in the design of the watch.

This parameter is relevant for models that have arrows and corresponding moving parts in the "stuffing" (wheels, gears, etc.). The stones in this case are, in fact, a specific kind of bearings used to fasten rotating parts. "Stones" are made from synthetic minerals (for example, artificial sapphires). They provide slightly less friction than traditional metal bearings, and most importantly, they are more reliable and less prone to wear, which accordingly affects the durability of the entire mechanism. However, it is worth noting here that these advantages are relevant mainly for mechanical watches (see “Mechanism type”), quartz models in this sense are not so demanding on bearings.

It is believed that the more stones, the better, but here it is worth considering the functionality of the device. So, for a watch with a central second hand, 16 jewels are considered sufficient, with a side one - 17, but if there are additional functions (calendar, days of the week, etc.), this number can increase accordingly. In addition, the presence of 40 or more stones is often not so much a real necessity as a publicity stunt.

A caliber can be described as the type of movement used in a watch. It is expensive and impractical to design a unique movement for each watch model, so most manufacturers often use the same movement in different watch models, sometimes with significantly different designs. The term "caliber" is due to the fact that initially the type of movement was designated by a number (in inch lines) corresponding to its largest size; however, today unique names or alphanumeric indices that are not directly related to sizes are widely used.

Knowing the name of the caliber on which the watch you are interested in is built, you can, if desired, find more detailed information about the mechanism and determine how its characteristics meet your requirements.

The accuracy of the rate is usually determined by the largest error — the deviation from the reference time, which can occur in a month when the watch is constantly running in normal mode. Accordingly, the smaller the number in this paragraph, the more accurate the clock. In addition, the accuracy of the movement is a kind of status indicator: if the error exceeds the values stated in the characteristics, this may indicate a malfunction in the mechanism.

If the accuracy indicators are the same both in advance and in lag, one number is indicated in the characteristics — for example, 30 sec / month (i.e. +/-30 sec / month); however, many mechanisms have unequal deviations, for example -15/+25 sec/month. Also note that this parameter is relevant only for quartz watches (see “Movement type”): in mechanical models, the accuracy of the rate is noticeably lower, it is measured in seconds not per month, but per day.

An indicator showing how long the watch can run without winding, changing the battery, recharging, etc. It is found in models with any type of mechanism (see the relevant paragraph). Although the power reserve indicator is quite approximate, it still makes it easier to monitor the status of the device and reduces the risk of being left without a working watch at the wrong time.

Note that the End Of Life function (see below) in this case is not considered a power reserve indicator, although its role is generally similar.

The amount of time that the watch is able to operate normally without winding the spring or changing/recharging the battery (for more details, see "Power source"). Modern mechanical watches (see “Movement type”) have a standard power reserve of 40+/-5 hours. However, this parameter is usually indicated for the simplest mode of operation, without the use of additional functions such as a chronograph(see “Functions / Capabilities” ), which also “eat up” the plant. Thus, such a watch is supposed to be wound every day, but nothing will happen if you miss the usual time and remember to wind it a few hours later than usual.

In turn, for quartz watches, the power reserve is often not indicated in the specifications. This is due to the fact that this parameter, firstly, is quite large compared to mechanical models (it would be measured in tens of days rather than hours), and secondly, it strongly depends on a number of external factors (for example, the quality of the next batteries). Therefore, it is very difficult, if not impossible, to reliably determine the power reserve in such cases.

The rotating bezel is a swivel ring around the dial, with marks applied to it (ring).

Usually the bezel scale is similar to the minute/second scale of the dial, it is marked from 0 to 60, most often with marks every 5 or every 10 minutes (seconds). In such cases, this function is a somewhat simplified analogue of the timer or stopwatch / chronograph used in watches with analogue dials. To work in the stopwatch mode, you need to align the zero on the bezel with the position of the second or minute hand (depending on how long the period needs to be detected), and at the end of the measurement, look at what division on the bezel this hand has reached. To work in the timer mode, zero on the rotary scale is set at the end of the countdown, and the user can only monitor whether the arrow has reached zero. Thus, you can turn the watch into a timer or stopwatch mode with just one turn of the ring — it's faster and more convenient than digging into the settings. Such features are appreciated, in particular, by scuba divers who use a timer to control air supplies; at the same time, in diving watches, the rotation mechanism is often made one-sided, so that the bezel cannot be accidentally turned in the direction of increasing the remaining time.

There are other types of rotating bezels — for example, in the form of a scale with cardinal points used in watches with a compass.

The presence of a case back made of transparent material in the design of the watch, allowing you to see the mechanism.

This element does not play a practical role, but it gives the watch an original appearance. Note that the transparent cover can be combined with a Skeleton, open balance (see below) and/or a transparent case (see above) case. The key differences between these features are that Skeleton and the open balance allow you to see the movement from the front, while the transparent case can be seen through, but the movement may not be visible.

As the name suggests, this parameter determines the degree of resistance of the watch to moisture. It is traditionally stated as the maximum depth under water at which the watch is able to remain watertight; however, it must be borne in mind that this number is very arbitrary. The fact is that when calculating the maximum immersion depth, only the static pressure of water is taken into account, that is, the pressure at complete immobility; at the same time, any movement creates dynamic pressure, which significantly increases the load on the body. In practice, this means that a mark of, for example, 50 m does not mean that you can dive to a depth of 50 m with a watch.

Modern water protection markings correspond to the following practical possibilities:

— 30 m(same as “Water Resistant” without any numbers). Entry level, drops of water are allowed, but not strong splashes. For example, such a watch can be left on in the rain or when washing, but when showering or washing a car, it should be left in a safe place. Of course, there is no talk of immersion in water.

- 50 m. Minimum water resistance, allowing the watch to be immersed in water. These watches can usually be used for swimming, and in some cases even jumping into the water (but not from towers), but they are not suitable for more serious tasks like surfing, snorkeling or scuba diving. As a rule, buttons are not allowed to be...used underwater.

- 100 m. This degree of water protection allows not only swimming, but also diving to shallow depths, however, it is still considered insufficient for surfing, jumping from towers and scuba diving.

- 200 m. Watches with such water protection are classified as “divers”; models and can withstand scuba diving to depths of up to 20 m.

- 300 m or more. Professional diving models suitable for diving to significant depths.

Please note that the characteristics described are approximate. Specific indicators of water resistance and the possibility of using the watch with water should be clarified according to the official data of the manufacturer.