Sea & Sea YS-D1

Manufacturer: Sea & Sea
Type: strobe
Year introduced: 2012
Discontinued: ~2015 (replaced by YS-D2)
Price at launch: $750

Overview

The Sea & Sea YS-D1 was announced in January 2012 as “the most advanced strobe Sea & Sea has produced in its 40-year history,” drawing inspiration from the YS-110, YS-110 Alpha, and YS-50Pro (^[1]). It was 25% more powerful and 10% smaller than the YS-110 Alpha. Originally previewed at DEMA Show 2011, where it was noted as having the same guide number (GN 32) as the much larger YS-250, though with a narrower beam angle producing a less powerful overall output (^[2]). The strobe shipped from February 2012 at a retail price of $750 (^[3]).

The YS-D1 became one of the most widely used underwater strobes of its era, employed by both professional and amateur underwater photographers. It remained in production until 2015 when it was superseded by the YS-D2, which retained the same core specifications while adding audible confirmation, glowing control dials, and a redesigned battery compartment (^[4]).

Specifications

(^[5])

Guide Number in Context

Alex Mustard, in his 2017 preview of the Retra strobe, conducted comparative guide number testing of the YS-D1 against other major strobes. He measured the YS-D1 with diffuser at GN 18 (ISO 100, in meters) — slightly higher than the Inon Z-240 (GN 16), Retra Flash (GN 16), Sea & Sea YS-250 (GN 16), and Ikelite DS-161 (GN 16) — but cautioned that this reflected the YS-D1’s narrower beam angle rather than superior power. He noted: “When the Sea & Sea D1 was released it was marketed as having the same guide number as the much bigger, more expensive Sea & Sea YS-250… but it of course has far less power than its big brother (it achieves the Guide Number because it has a narrow beam). The solution many Sea & Sea D1 owners use is to add a dome diffuser, which increases the angle of coverage, but also drops the Guide Number considerably” (^[6]).

Key Features

• DS-TTL II exposure control with exposure compensation adjustment of +/- 4 EV steps — the first Sea & Sea strobe with this capability (^[7]).
• Built-in high-intensity LED target light for focusing assistance in dark conditions (^[8]).
• Auto-sensing slave switch that automatically detected slave triggering mode (^[9]).
• Pre-flash cancellation mode for compatibility with digital camera pre-flash systems (^[10]).
• Three LED indicator lights: red (ready), green (TTL confirmation), blue (Slave TTL mode) (^[11]).
• Auto power OFF function to preserve battery life (^[12]).
• Safety valve on the battery cap for gas venting in case of battery malfunction, hidden under the label of the battery cap. Brook Peterson confirmed this feature worked during an actual battery explosion: “The back cap of my Sea&Sea YS-D1 strobe had a safety valve that burst with the explosion” (^[13]).

TTL Triggering & Converter Compatibility

The YS-D1 was supported by a wide ecosystem of TTL converters and flash triggers:

• Nauticam Flash Trigger for Canon (July 2013, $220): Provided manual-mode fiber optic triggering for Canon cameras without pop-up flashes (5D Mark III, 6D, 1D X). The YS-D1 required an optional flash prism (model 26312 or 26313) for reliable triggering (^[14]).
• TRT-Electronics Turtle TTL strobe trigger (November 2016, EUR 599): Supported the YS-D1 in both electrical triggering (via Nikonos sync cord) and optical triggering modes. Compatible with all Canon and Nikon DSLRs (^[15]).
• TRT-Electronics o-Turtle for Olympus (November 2017): Tested with the YS-D1 in both electrical triggering mode and optical triggering (with included LEDBOARD and multicore cables). Compatible with Olympus MILC systems including OMD E-PL3, E-M5, E-M5II, E-M10II, E-M1, and E-M1II (^[16]).
• UW Technics External Optical TTL Converter (2017): The first external optical TTL converter available for the YS-D1 with Nikon cameras. In TTL mode, the strobe was simply set to TTL; in manual mode, it was set to manual without pre-flash, with output controlled by the strobe’s light level control dial (^[17]).
• UW Technics TTL Converter for Canon (August 2017, $450): Internal converter for Nauticam housings supporting the YS-D1 alongside Inon Z-240, Sea & Sea YS-D2 and YS-250, and Ikelite strobes. Strobe type selectable via camera dial switch (^[18]).
• UW Technics TTL circuit for Nauticam NA-EM1X (June 2019): Firmware contained accurate TTL profiles for the YS-D1 among other strobes, with strobe type set by onboard 10-position rotary switch (^[19]).
• UW Technics TTL Converter for Sony (July 2019): Compatible with Sony A7 series (A7S II, A7R III, A7 III, A7 IV, A9) in Nauticam housings, with YS-D1 listed among supported strobes (^[20]).

The YS-D1 was also compatible with electrical triggering via Ikelite sync cables with Sea & Sea connectors, allowing use with Ikelite housings (^[21]).

Third-Party Accessories

• Retra Prime LSD (Light Shaping Device): Compatible with the YS-D1 for light control in macro photography (^[22]).
• CM Diffusers dome diffusers: The Series II dome diffuser for the YS-D1/D2 was completely redesigned in 2018 with frosted material for enhanced light transmission and improved center-to-edge fall-off, priced at $75 each (^[23]). Professional photographer Allison Vitsky Sallmon used YS-D1 strobes with “40% CM dome diffusers” for wide-angle work (^[24]).
• 10bar Macro Snoot Set: Compatible with the YS-D1, YS-D2, YS-D2J, and Inon Z-240/Z-330. Featured a laser aiming light and removable front sections to adjust beam size (^[25]).
• Saga ring flash: Could be used with the YS-D1 for macro photography, as demonstrated by Allison Vitsky Sallmon (^[26]).
• YS base mount: Shared across the YS-D1, YS-D2, and YS-D3 strobe families (^[27]).
• Flip Snoot Pro (onderwaterhuis.nl): Used by photographers with the YS-D1 for macro snooting, including a Hugyfot-housed Nikon D7100 configuration (^[28]).

Notable Users & Usage

The YS-D1 was used by a range of underwater photographers, from professionals to serious amateurs:

• Justin Hofman used dual YS-D1 strobes with a Sony A7R II and Sony 16-35mm F4 lens in a Nauticam housing with a Sea&Sea 240mm dome to capture his famous viral seahorse image — a small estuarine seahorse (Hippocampus kuda) clinging to a plastic cotton swab. The image was shortlisted for Wildlife Photographer of the Year 2017 (^[29]).
• Allison Vitsky Sallmon and Andy Sallmon used dual YS-D1 strobes for macro photography with Canon 7D and 70D cameras, including snooted lighting for nudibranch photography and ring flash setups for whip coral shrimp. Allison’s setup included an Aquatica housing for a Canon 5D Mark III with a 9.25-inch dome port, four strobes total — two Sea and Sea YS-120s and two YS-D1s, “all four using 40% CM dome diffusers” (^[30]).
• Robert (Wetpixel contest winner) used dual YS-D1 strobes with a Nikon D300 and Tokina 10-17mm fisheye at 16mm to photograph the wreck of the Satil off Eilat in the Northern Red Sea (f9 at 1/125) (^[31]).
• Kraken de Mabini (prolific forum contributor) used YS-D1 strobes with a Nikon D800E and Nikkor 105mm in a Subal housing for macro work in the Philippines (^[32]).
• phxazcraig continued using older YS-D1 strobes with a Nikon Z9 in a Nauticam housing as late as 2022-2023, later noting they were “much better” after eventually switching to newer alternatives (^[33]; ^[34]).
• toque used YS-D1 strobes with a Sony A6600 and UW Technics flash trigger as late as July 2023, encountering sync issues at higher power settings (^[35]).
• Sea & Sea provided YS-D1 strobes as prizes for the 2014 SoCal Shootout underwater photography competition (^[36]).

Compatibility with Housing Systems

The YS-D1 was widely supported across housing manufacturers:

• Sea & Sea MDX housings: The YS-D1 was a native companion strobe for Sea & Sea’s Internal Optical YS Converter, introduced with the MDX-70D housing. The converter provided sync-cord-like TTL accuracy via fiber optics, compatible with YS-D1, YS-01, and YS-110alpha (^[37]).
• Nauticam housings: Fiber-optic triggering with optional flash prism for reliable firing. Many Nauticam housing announcements listed the YS-D1 as a compatible strobe option (^[38]).
• Subal housings: Featured optional optical strobe connectors for fiber optic triggering with YS-D1 and Inon Z-240 “no sync cords needed.” A visual and audible leak alarm came as standard (^[39]).
• Hugyfot housings: Used by at least one photographer (with a Canon 7D) complemented with a YS-D1 strobe and Flip Snoot Pro (^[40]).

Alex Mustard’s Assessment

Alex Mustard provided the most comprehensive comparative assessment of the YS-D1’s lighting performance in his 2017 Retra strobe preview. Comparing it head-to-head against the Inon Z-240, Sea & Sea YS-250, Ikelite DS-161, Seacam 150, and Subtronic 270 in the Bahamas, he found:

The YS-D1 recorded a slightly higher guide number (GN 18 with diffuser) than the other mid-range strobes (all GN 16), but “had a noticeably narrower coverage than even the INON Z240.” He positioned the YS-D1 as the primary upgrade target for the Retra Flash, noting it was “a similar size to both [Inon Z240 and Sea & Sea D1]” and used the same 4x AA batteries and Sea & Sea electronic sync cables. The Retra “out-guns its Japanese rivals with much wider, more even light and a bit more power” (^[41]).

In the 2023 “Which strobe for FF system” thread, Mustard offered a characteristically wry assessment of Sea & Sea strobe quality: “I recommend people use crappy strobes. For years I have enjoyed superior lighting to other photographers and it has been very annoying that now so many photographers have Retras, I have lost this advantage… So don’t spend money on good light. When has light ever been important in photography” (^[42]).

Successor: YS-D2

The YS-D2 was announced in July 2015 at a retail price of $719.95, described as keeping “the same great performance specs as the YS-D1” while adding several usability improvements (^[43]):

• Audible confirmation of TTL exposure and ready state
• Rear glowing panel with illuminated, easy-to-read controls
• Wing nut style fixing bolt
• Redesigned control knobs and battery compartment
• Dual powered target light with red filters
• Slightly faster recycle time: 1.5 seconds (vs. 1.9 seconds for YS-D1)

The YS-D2 maintained the same guide number (GN 32), diffuser system, and triggering compatibility as the YS-D1. The strobe line was later revised as the YS-D2J (Japanese-produced version in 2017) and eventually replaced by the YS-D3 Lightning in 2020, which introduced a new aspherical toroidal lens, dual flash tubes, a higher guide number of 33 with a wider native beam angle of 105 x 80 degrees, and a more powerful target light approximately four times brighter than the YS-D2. The YS-D3 also featured larger capacity condensers and a newly designed charging circuit enabling continuous firing at GN 16 with no interval time, and firing at GN 22 with only 0.8 second recycle (^[44]).

Reliability & Known Issues

Community discussion on Wetpixel forums documented several recurring issues with the YS-D1 — and these reliability concerns became one of the defining narratives of the Sea & Sea strobe line through the D2 and beyond.

Battery Compartment & Moisture Ingress

Multiple users reported moisture entering the electronics compartment, leading to short circuits, burned transformers, and erratic behavior such as continuous random firing and the target light staying permanently on. The battery cap O-ring was identified as the most common failure point due to daily opening and closing (^[45]). One user (Karim) reported finding “marks of fire explosion inside” the electronics compartment after a flood, with a burned humidity/desiccant sac inside. Kraken de Mabini, who had “opened and disassembled several Sea & Sea YS-D1 strobes,” confirmed that none had desiccant packs from the factory, suggesting a previous owner had added it after detecting a leak (^[46]).

Another user (DiveDude) reported moisture visible in the front of the housing after fresh water use, with the LED glowing solid and the flash not firing — a similar failure pattern. Adam Hanlon cautioned about the dangers of working on strobe internals: “The capacitors generate and can hold a significant charge, which can damage you if you don’t discharge it safely” (^[47]).

A third user reported the strobe flooding and bursting during a safety stop, with the water entry traced to the electrical cable socket (^[48]).

Battery Safety

Photographer Brook Peterson reported an Eneloop battery exploding inside a YS-D1 strobe while diving. The battery cap’s hidden safety valve burst with the explosion, demonstrating the safety mechanism worked but requiring the cap to be replaced afterward. This incident was reported in the comments of a Wetpixel article noting that Panasonic specifically warns against using Eneloop batteries in “underwater lights or other airtight appliances” due to the hydrogen gas venting risk (^[49]). The article noted that despite this guidance, “many, many images have been taken with strobes that have been powered by Eneloop batteries since they were first released in 2009.”

Cracking Housing

At least one user reported the YS-D1 cracking around the battery housing, rendering it unfixable (^[50], community comment).

Sync Issues at Higher Power

Forum user toque reported that YS-D1 strobes paired with a Sony A6600 and UW Technics flash trigger would sync correctly only up to the 0.7 mark on the power dial, with “any notch higher all the way to ‘Full’ and the strobes were not in sync with the camera.” This was attributed to pre-flash interaction issues, though the exact cause remained unresolved (^[51]).

Repairability

Forum member Kraken de Mabini, who disassembled several YS-D1 strobes, provided the most detailed description of the internal construction. The electronics consisted of “two parts: the transformer and capacitor circuit for high voltage, and a second circuit with micro-computer chips and dozens of tiny components.” The first circuit was “easy to inspect and repair,” but the second was “a set of highly complex and very delicate circuits; for example with two micro-computer chips, plus dozens of tiny chips that break off easily. As such the electronics are non-repairable by us ordinary mortals.” He noted that “the wiring that connects the boards is delicate, and soldered, not connected by plugs,” making reassembly extremely risky. Adam Hanlon also cautioned that strobe capacitors can hold dangerous charges even after batteries are removed (^[52]).

Regarding servicing options, Kraken de Mabini reported: “I asked two major US outlets if they repaired defective S&S or Inon strobes, their reply was to buy a new one” (^[53]). For the YS-D2 (which shared similar construction), he recommended “sending the strobe back to Sea&Sea” at their Tokyo headquarters as the best approach (^[54]).

Broader Sea & Sea Reliability Concerns

Community members frequently noted Sea & Sea strobe reliability issues compared to competitors. Forum user Barmaglot observed that while the YS-D1 and its successor YS-D2 used “very similar or the same components” as older models, manufacturers pushed components harder in newer designs, “resulting in reduced service life and higher failure rates.” The YS-D2 was described as “particularly badly affected,” with the Japanese revision (YS-D2J) “also known for fairly frequent failures” (^[55]).

Multiple users reported migrating from Sea & Sea strobes to Inon or Retra alternatives. Forum user pooley stated they were “much better than my old Sea and Sea YS-D1’s” after switching to Retra Pro strobes (^[56]). Forum user Architeuthis reported four YS-D2 strobe failures since 2017, leading them to consider Sea & Sea YS-D3 “out of discussion” and instead evaluate Retra Pro X, Seacam 160, or Ikelite DS230 (^[57]).

In the YS-D3 vs. Inon Z-330 comparison thread, oneyellowtang noted that “Sea & Sea struggled with quality & support for a few years” and recommended the Inon, while Kraken de Mabini stated he had “owned several Sea&Sea and Inon Z strobes, and still prefer the Inon Z240’s” (^[58]). Canadian user stoo reported that “Sea & Sea seem to regularly have issues and in Canada, that means shipping to Japan for repair and from what I’ve heard, that literally never ends well” (^[59]).

Market Context

The YS-D1 competed primarily with the Inon Z-240, which was considered “pretty much indestructible” and held its resale value well, with even quite old examples selling “very quickly at a surprisingly high fraction of their original price” (^[60]). Other competitors included the Ikelite DS-160/DS-161 series (which used proprietary batteries rather than AA cells) and the Subtronic Pro series. The YS-D1’s use of standard AA batteries was seen as an advantage for travel and availability, with Barmaglot noting that Eneloop Pro 4-packs cost “less than $20” compared to “$200” for Ikelite proprietary battery packs (^[61]).

The Retra Flash (later Retra Pro), which began shipping in 2017, was explicitly designed as a “performance upgrade for photographers currently shooting INON or Sea & Sea D1/D2 etc strobes,” matching their form factor, battery type, and sync cable compatibility while offering wider, more even light (^[62]).

The strobe was shown at The Dive Show 2012 following its DEMA 2011 debut (^[63]). It was also frequently bundled as a compatible strobe option with housing announcements from Nauticam and Sea & Sea throughout 2012-2015, appearing in product specifications for numerous housing packages.

Wetpixel Live Coverage

Adam Hanlon and Alex Mustard discussed strobe longevity and maintenance in Wetpixel Live Episode 211, “How Long Do Underwater Strobes Last?” The episode addressed the lifespan of underwater strobes including the YS-D1 and its successors, covering topics such as capacitor degradation, O-ring maintenance schedules, and when to replace aging strobes (^[64]).

Resale Market

The YS-D1 appeared regularly on the Wetpixel classifieds. In June 2022, a pair of YS-D1 strobes was offered at $500 (approximately $250/strobe) (^[65]). The used market for YS-D1 strobes remained active into 2022-2023, with some buyers seeking them as budget options despite the reliability concerns (^[66]).

Timeline

• 2011-11: Previewed at DEMA Show 2011 in Orlando, Florida. Same GN 32 as YS-250 noted, but with narrower beam (^[67])
• 2012-01: Officially announced by Sea & Sea USA, priced at $750 (^[68])
• 2012-02: Shipping begins (^[69])
• 2012-10: Displayed at The Dive Show 2012 (^[70])
• 2013-02: Compatible with Retra Prime LSD light shaping device (^[71])
• 2013-07: Nauticam Flash Trigger for Canon adds YS-D1 compatibility with flash prism (^[72])
• 2013-12: Listed as primary compatible strobe for Sea & Sea MDX-70D housing with Internal Optical YS Converter (^[73])
• 2014-08: Sea & Sea provides YS-D1 strobes as prizes for the SoCal Shootout competition (^[74])
• 2015-07: Superseded by YS-D2 at $719.95, with same GN 32, faster 1.5s recycle, audible TTL confirmation (^[75])
• 2016-11: TRT-Electronics Turtle TTL trigger supports YS-D1 (^[76])
• 2017-02: Alex Mustard publishes comparative strobe test positioning YS-D1 against five competitors (^[77])
• 2017-03: UW Technics External Optical TTL Converter reviewed with YS-D1 support (^[78])
• 2017-08: UW Technics Canon TTL Converter supports YS-D1 (^[79])
• 2017-09: Justin Hofman’s seahorse image, shot with dual YS-D1 strobes, shortlisted for Wildlife Photographer of the Year 2017 (^[80])
• 2017-11: TRT-Electronics o-Turtle for Olympus tested with YS-D1 (^[81])
• 2018-02: CM Diffusers releases redesigned Series II dome diffuser for YS-D1/D2 (^[82])
• 2018-04: Brook Peterson reports Eneloop battery explosion inside YS-D1 strobe; safety valve functioned correctly (^[83])
• 2020-04: YS-D3 Lightning ships as next-generation successor, with new aspherical toroidal lens and dual flash tubes (^[84])
• 2022-2023: Still in active use by some community members; used YS-D1 pairs selling for approximately $250/strobe on secondhand market (^[85])
• 2023-07: Forum user reports sync issues with YS-D1 strobes on Sony A6600 at higher power settings (^[86])

References

Wetpixel Live