SKU: 03129

  • ₱42,500.00
    Unit price per 


The YS-D3 DUO is a high-specification underwater strobe with three shooting modes: DS-TTL, RC mode, and manual. This delivers even and uniform light distribution with a large light output of GN33. Custom settings allow the strobe to be used with high precision with a variety of cameras and shooting styles.


The mode switch can be used to switch between "DS-TTL", "RC mode", and "Manual". It is conveniently identifiable by color.

Blue : DS-TTL
Red : RC mode
Orange : Manual 1


Highly accurate DS-TTL dimming

DS-TTL dimming accuracy has been greatly improved by adopting a newly designed light-receiving sensor.

By applying detailed custom settings, it can be used with high accuracy with a wide variety of cameras of multiple brands.

*When shooting TTL with a camera of a brand other than OM SYSTEM (OLYMPUS), select DS-TTL as the shooting mode.
*Pre-custom settings must be made for each camera in advance when shooting with DS-TTL.
In DS-TTL mode. Exposure compensation can be made with the light level control dial on the right. +2.0 to -2.0


Highly accurate DS-TTL dimming

The "RC System" is a flash system for OM SYSTEM digital cameras, and the YS-D3 DUO was developed in collaboration with OM Digital Solutions to incorporate the RC mode.

RC mode is a light control mode in which the camera automatically controls the flash output based on the brightness through the lens. The YS-D3 DUO is equipped with a more precise "RC mode" that was developed based on system information officially provided by OM Digital Solutions. The YS-D3 DUO is equipped with a more precise "RC mode" developed based on the system information officially provided by OM Digital Solutions.

*Since the strobe is system-linked to the camera, flash output compensation can be adjusted not only on the strobe side but also on the camera side while shooting in RC mode.
*Setting the camera to RC mode can prolong (save) the camera's battery life.
In RC mode. The light level control dial on the right can be used for exposure compensation.


Manual mode has 11 steps

In manual mode, light intensity can be adjusted in 11 steps. The settings are (GN: 1 / 1.4 / 2 / 2.8 / 4 / 5.6 / 8 / 11 / 16 / 22 / 33). The value can be easily seen on the scale on the light intensity adjustment dial. Compatible with digital cameras that do not have a pre-flash function.

*Only manual flash is available, but if your camera housing is equipped with a strobe connector/converter connector, you can also use a sync cord to connect the strobe.

In manual mode. Select the guide number with the light level control dial.

YS-D3 DOU can also be connected with a sync cord



The YS-D3 DUO can be set up with high precision to accommodate a variety of shooting styles with different cameras by making custom settings. Refer to the table for settings according to the shooting mode used and the method of synchronizing the camera and strobe.


Shooting in DS-TTL mode and manual mode

  • Click here to shoot with DS-TTLusing an optical/TTL converter.

*Custom settings are not required when using manual trigger. Use the default settings.

  • When shooting in DS-TTL/Manual using the built-in flash.

Nikon Canon Sony Others

*See page E-28 of the instruction manual for procedures to change custom settings.


Shooting in RC mode

When shooting in RC mode with an OM SYSTEMS (OLYMPUS) camera, no custom settings are required. Select "RC mode shooting" in the flash mode setting on the camera side; YS-D3 DUO should be set to "RC" for shooting mode.

*For details on "RC mode shooting," please refer to the user's manual of the camera to be used.



This is a high-performance strobe that pursues quality of light, and its high luminous flux and wide beam angle are effective for wide-angle photography with fish-eye lenses and other wide-angle lenses. The strobe also features our proprietary light distribution technology.

High light intensity GN33

The light output has a guide number (GN) of 33, one of the highest among general-purpose underwater strobes. The use of two discharge tubes increases power and achieves GN 33 at full flashing.

Two discharge tubes


Uniform and even light distribution

The originally developed "aspherical toroidal lens" is placed in front of the light-emitting tube, and the two discharge tubes and the "aspherical toroidal lens" provide uniform and even light distribution to the periphery, making it an ideal light source for external illumination.

Aspherical optical troidal lens




Adjust beam angle with diffuser

The beam angle is 80°×105° without the diffuser and 100°×110° with the included diffuser for soft lighting.

When the optional dome diffuser is attached, the beam angle increases to 150°×170°. The dome diffuser is effective when using a fisheye lens or when lighting with soft light (guide number is reduced by approximately -1.5 EV).

Without diffuser

With attached diffuser

Dome diffuser installed

Without diffuser

With attached diffuser

Dome diffuser installed



We placed particular emphasis on ease of use, especially underwater handling. The more you use it, the more you will appreciate its easy-to-turn dial, easy-to-see panel display, and good underwater balance.

Large dial

Underwater operation is performed with the mode switch and light intensity control dial. The large dials are non-slip and the height difference allows smooth operation even when wearing thick gloves. It is designed to stop in steps with a click-click to minimize malfunctions.

Large dial


Easy-to-read backlit panel

The indicator color changes each time the mode switch is repositioned. Blue (in DS-TTLII mode), red (in RC mode), yellow (in manual mode with pre-flash), and green (in manual mode without pre-flash) are the different colors for identification, so positioning of the controls is easy to see even when night diving.

In DS-TTLII mode

In RC mode

In manual non pre-flash mode



Underwater Balance

YS-D3 DUO has almost zero buoyancy with the ball mount and clamp in place. Heavy underwater weight requires unexpected force to operate the clamp, but the YS-D3 DUO is unaffected by buoyancy, so operation is smooth. Even if you change the strobe position, the underwater balance of the entire housing set does not change significantly and you can feel how easy it is to handle.


Two patterns of target lights

The LED target light function is useful for focusing and checking the beam angle of the strobe. Choose either 300 lumens or 150 lumens depending on the situation.

300 lumen

150 lumen


One-touch battery replacement

The power source is AA batteries, which are widely distributed in general. Four of the same type (1.5V alkaline AA batteries and 1.2V nickel-hydrogen AA batteries). The battery box is opened and closed by a bayonet type that does not put a burden on the O-ring. It is a one-touch operation and does not require force like the screw-in type.


Hook for Fiber Optics

A hook for fiber-optic cable on the strobe body smartly guides the fiber-optic cable.


How to connect with the arm of your choice

A straight type ball base is included, but the YS base or Strobe Ball Base 35 can be attached as an option depending on the application.

YS base

Diagonal ball base


Diagonal ball base system example




A wide variety of accessories expand the shooting range.



An adapter that turns a strobe light into a spot light. An internal prism allows the optical axis of the target light to be perfectly aligned with the optical axis of the strobe light. The beam aperture is 25mm and the use of a snoot cuts off light around the subject to make only the subject stand out.


Dome diffuser


Diffuser that widens the beam angle to 150° x 170°. Light intensity is reduced by approximately -1.5 EV (GN28).


Flash prism


Light guiding prism that can emit YS-D3 DUO light without using





  • [Beam Angle] : 80°x105° (without Diffuser), 100°x110°(with Diffuser)
  • [Usable Batteries] : 4xAA A: 6V Ni-MH: 4.8V
  • [Number of Flashes *1] : A: 140 Ni-MH: 220
  • [Recycle time (full) *2] : A: 3.5 sec. Ni-MH: 1.7 sec.
  • [Color temperature] : 5800K (w/diffuser 5500K)
  • [Depth rating] : 100m / 330ft
  • [Dimensions (WxHxD)] : 92x111x147mm / 3.6 x 4.4 x 5.8 inches (excluding ball base)
  • [Weight] : 610g / 21.5oz (w/o batteries) (excluding ball base)
  • [Underwater weight] : Approx.-20g / -0.7oz (incl. batteries ball base)
  • [Others]
  • Exposure control: DS-TTL II, Light level control dial (GN): 1 / 1.4 / 2 / 2.8 /4 / 5.6 /8 / 11 / 16 / 22 / 33 (11 steps)
  • Pre-flash cancel function
  • Auto power OFF function
  • Sync cord: 5-pin Sync cord/N, Fiber-Optic Cable
  • Over-pressure relief valve
  • LED target light (output is adjustable in 2 steps [300lumen/150lumen])
  • Audible charge signal
  • [Set Items] Ball Mount Strobe Adaptor、Diffuser、Slicon grease
*1 Number of flashes and recycle time depends on the battery brand, temperature and frequency of use.
*2 Number of flashes and recycle time of Ni-MH batteries were tested on 2500 mAh batteries.



* Use of genuine SEA&SEA Fiber-Optic Cables is recommended. SEA&SEA strobes may not function properly if a third-party Fiber-Optic Cables are used (functions such as TTL auto exposure in particular).
*Do not use non-recommended batteries (such as lithium primary batteries). Use of non-recommended batteries may cause battery leakage and overheating and may cause the strobe to rupture, which could result in personal injury.