Keldan

Type: Manufacturer (underwater video lights, filters, accessories)
Founded: Switzerland
Founder/Owner: Daniel Keller
Website: keldan.ch (formerly keldanlights.com)
Key products: Solaris, Luna, Video 4X/8X/8M/18X/24X series, Spectrum and Ambient filters, RC1 remote control

Overview

Keldan is a Swiss manufacturer of high-end underwater video lights, founded and run by engineer Daniel Keller. The company is known for precise color rendering, exhaustive lab-tested specifications, modular design, and professional build quality. Keldan distinguishes itself from competitors by emphasizing Color Rendering Index (CRI) accuracy over raw lumen output, providing detailed measured spectral data rather than calculated estimates. (^[1])

Eric Cheng described Daniel Keller as “the understated engineer who runs Keldan” and noted that “Keller is not afraid to show detailed test results from the exhaustive measurements he conducts in his lab.” (^[2]) This engineering-first approach has been a consistent hallmark of the brand: all Keldan specifications are measured at operating temperatures in real-world conditions, not calculated from LED vendor datasheets. (^[3])

Keldan’s distinctive purple-colored light housings make them easy to identify at trade shows and underwater. (^[4])

History

Early HID Era (pre-2006)

Keldan’s earliest products were HID (High Intensity Discharge) dive lights. The Solaris line used a medical-grade HID burner that emitted pure white light, distinguishing it from the typical bluish cold light of competing HID lights. The Solaris was available in multiple configurations varying in burn time from 60 to 400 minutes, including handheld and canister models. The reviewer Eric Altermann noted the Solaris Pro used NiMH batteries, had two power settings (45W and 60W halogen-equivalent), featured integrated charging electronics, an emergency LED backup light, and was depth-rated to withstand professional diving conditions. Retail price was approximately $800-$1,430 USD depending on model and exchange rates. (^[5])

At DEMA 2006, Keldan debuted the Luna 8 WA video light alongside the existing Solaris line. Eric Cheng described Keldan’s booth as “just about the brightest area at DEMA.” Daniel Keller demonstrated the Luna 8 WA, which featured variable power (8 levels from 14-28W), a removable lithium-ion battery, 100 minutes burn time at full power, 5200K color temperature, and a 20-degree beam angle (60 degrees with diffuser). The Luna 8 WA was self-contained and priced at $1,872 including diffuser, bracket, and ULCS ball adapter. The Solaris Tec 24 was also shown, with a similar design but detached battery and light head. (^[6])

At the same show, Keldan was noted in the video products roundup as “a swiss company” with “2 video lights on display, the component (lamp and battery separated).” (^[7])

HID to LED Transition (2007-2009)

At DEMA 2007, Keldan showcased the Luna 8 WA-V, an adjustable 18-25W HID video light with five power levels and 60-degree beam angle with diffuser. The Luna 8 ran for 130 minutes on high or 180 minutes on low, charged in 7 hours, and weighed only 0.27 kg in water. Also displayed was the Movie 24 WA-V video light set. (^[8])

At DEMA 2008, Keller showed two HID video lights: the Luna 4 BS-V (30W, 1400 lumens at 5500K, CRI 70, $1,256) and the Luna 8 WA-V (25W, 1500 lumens at 5000K, CRI 85, $1,608). Both were also available as dive lights. Eric Cheng noted that “Keldan lights feel great in one’s hands, and the on/off switch is easy to operate.” (^[9])

The transition to LED technology was a pivotal moment. By DEMA 2009, Keldan showed the Luna 8 LA-V, their first high-CRI LED light, which would ship in 2010 with a measured CRI of 95 (Ra) — remarkable because LED efficiency typically decreases as CRI increases. (^[10])

LED Breakthrough and US Distribution (2010-2013)

In March 2010, Nocturnal Lights became the official North and South American distributor for Keldan. The Luna 8 LA-V was the flagship product: a 40W LED video light with 2100 lumens, CRI of 95, 80-minute burn time at max power, and a 90-degree beam angle. (^[11])

Eric Cheng’s review of the Luna 8 LA-V praised the light’s quality extensively. He tested two units in the Maldives and described the light as “absolutely beautiful — the smoothest, most even lights I have used.” The proprietary 40W, 5000K LED produced 3100 lumens at the bulb (2100 measured lumens). The light weighed 2.5 lbs on land and 0.31 lbs underwater, was rated to 200 meters, featured a magnetic switch with lock, five output levels, and full thermal protection allowing use on land. At $1,996 per light, Cheng acknowledged the premium price but concluded that “cameramen who are working at a high level will definitely find these lights to be worth every penny.” (^[12])

At DEMA 2010, Equinox announced plans to sell the Keldan range of video lights. (^[13])

In January 2011, Keldan increased the Luna 8 LA-V CRI’s output by 50% to 4000 lumens (3000 measured at the window) while maintaining the CRI of 95. (^[14])

Steve Douglas published an extensive review of the updated Luna 8 LA-V CRI in July 2011, testing it in Kona, Hawaii during the famous Night Manta Dive. He noted the light “easily outshone” a competing top-of-the-line light “with both a wider dispersion, cleaner light, and longer throw.” The review explained that Keldan produced two models: the Luna 8 LA-V Flux (5000 lumens, optimized for maximum output) and the Luna 8 LA-V CRI (3000 lumens, optimized for color accuracy at CRI 95). Both offered power settings from 15 to 65 watts and 90-degree coverage. The CRI model retailed at $2,199. (^[15])

In 2012, the Luna 4V compact video light shipped at $1,500, designed for smaller video setups and DSLRs. It offered 4000 lumens with five power settings, 5000K color temperature, and 80-degree beam angle in water. (^[16])

At the London Dive Show 2012, Keldan displayed the Luna 4V alongside their other products. (^[17])

Modern Video Light Era (2014-2017)

Distribution in the Americas shifted from Nocturnal Lights to Nauticam USA by 2014. (^[18])

In September 2014, Keldan launched the Video 4X — 6000 measured lumens, 110-degree usable beam angle, CRI of 82, 45-minute burn time at full power, and a new custom reflector and dome lens unit. Priced at $1,540. (^[19])

In December 2014, two major products shipped simultaneously:

• Video 8X — 10,000 measured lumens at 5000K with CRI 82, 90-degree beam angle, 42-minute burn time, $2,190. This was described as “the brightest KELDAN to date.” (^[20])
• Video 8M (modular) — Available in two variants: 8M Flux (9000 lumens, CRI 83, $1,980) and 8M CRI (8000 lumens, CRI 96, $2,090). The modular design allowed swappable LED modules including Flux, CRI, Cyan (30,000K for ambient light matching), UV (400nm for fluorescence), Blue (450nm for yellow-filter fluorescence), and Deep Red (655nm, invisible to fish for nocturnal observation). (^[21])

The 8M modular system was a significant innovation, allowing professionals to choose the optimal light module for each shooting situation. Owners of previous “8” series lights could upgrade by purchasing new LED modules. (^[22])

In May 2016, Keldan announced three updated products: the new Video 8X CRI (8000 lumens, CRI 96, $1,990), an upgraded Video 8X Flux (now 12,000 lumens, $1,890), and an upgraded Video 4X (now 7000 lumens, $1,370). (^[23])

In April 2017, the Video 8X 11000lm CRI92 was announced — a significant step forward combining 11,000 lumens with a CRI of 92 at 5400K. The light featured 9 step power regulation ranging from 270 lumens (20-hour runtime) to 11,000 lumens (45-minute runtime). (^[24])

At DEMA 2017, Keldan showed across-the-board upgrades powered by new batteries: the 4X reached 9000 lumens, the 8X reached 15,000 lumens, the 18X reached 25,000 lumens, and the 24X reached 30,000 lumens. All lights were standardized to 5600K color temperature. The domes were manufactured from tougher material with scratch-resistant coating, and battery packs featured graphical status displays with digital readout of remaining burn time. New flotation brackets were also introduced. (^[25])

Spectrum and Ambient Filter System (2017-2019)

Beginning in 2016-2017, Keldan developed an innovative filter system to address a fundamental challenge of underwater videography: matching artificial light color temperature with ambient light for natural-looking footage.

At DEMA 2017, Daniel Keller introduced the Spectrum gel color correction filter, a dichroic filter constructed of multiple thin layers that would never bleach like colored filters. Designed to fit behind the lens, it extended the usable color spectrum at depth. Keller recommended that white balance be set at 20 meters and held at greater depths for best results. A specific Spectrum filter for the Nauticam WWL-1 wet lens was also announced in three strengths: S1 (2-7m), M2 (5-12m), and D2 (7-15m). (^[26])

In December 2017, Keller published a video demonstrating the filter system’s effectiveness, using a side-by-side rig with two Canon 70D cameras (one with Spectrum filter, one without). The tests showed that the effective complete absence of red below about 18-20 meters causes many cameras to fail at white balancing or produce inaccurate results. (^[27])

The filter system shipped by early 2018, as confirmed at Boot Dusseldorf. (^[28])

In February 2019, Keldan released animated tutorial videos explaining how Ambient Light filters and Spectrum filters work together. The Ambient Light filters attach to Keldan’s 4X and 8X lights and correct their output to match the spectrum of light occurring underwater at specific depths. The Spectrum filters attach to the camera lens and compensate for colors lost in the water column. The two systems can be used independently or in combination. (^[29])

Massimo Franzese (Interceptor121) published a detailed review testing the revised Spectrum and Ambient filters at Tiger Beach, Bahamas. The Spectrum -2 filter offered 4 meters of depth color compensation at the cost of 2 stops of light; the -4 filter offered 8 meters at 4 stops. Ambient filters were available in 6m and 12m depth simulations and in blue, green, and blue-green variants for different water types. Franzese found the color rendering “truly superb across the whole frame” and noted that “both divers and fish a few meters behind the subject are perfectly in color balance with the foreground.” He also tested the filters for still photography with strobes, concluding the color rendering was “genuinely phenomenal.” Keldan does not recommend filter use past 20 meters depth. (^[30])

Remote Control and Recent Products (2020-2023)

The 2020 product line brought comprehensive upgrades: the 8X CRI reached 15,000 lumens with CRI 95, the 8X Flux hit 18,000 lumens with CRI 85, and the compact 4X reached 10,000 lumens with CRI 85. Two new high-output models were introduced: the Video 18X (30,000 lumens) and Video 24X (35,000 lumens), both at 5600K with 9 power levels. The Spectrum and Ambient filter ranges were streamlined and refined, and a buoyancy collar accessory was introduced for 8X/8M lights providing 150g of buoyancy. (^[31])

In July 2020, Keldan shipped a pocket-sized underwater Color Checker — a rigid fiberglass card with a 24-patch X-Rite ColorChecker on one side and an 18% neutral grey card on the other, designed for precise underwater color calibration. (^[32])

In December 2020, Keldan introduced the RC1 Remote Control, a wireless underwater controller using ultrasound (sonar) technology. The RC1 could control the brightness of 24XR and 18XR lights across two independent channels, with a range of 50 meters that worked “around corners and through walls.” Each channel could address an unlimited number of lights, and separate IDs prevented interference when multiple controllers were used at the same dive site. The Video 8M Flux was also upgraded to 11,000 lumens (from 9,000). (^[33])

Daniel Keller demonstrated the RC1 to Adam Hanlon on Wetpixel Live, explaining the ultrasound technology that enables control even without line-of-sight. (^[34])

In March 2022, the Video 8XR shipped — a 20,000-lumen light (CRI 86) that brought RC1 remote control compatibility to the compact 8X form factor. Keldan noted that fitting all the remote control electronics into the smaller housing was a significant engineering challenge. (^[35])

Natalie Gibb, a cave explorer and underwater image maker, tested the 8XR and RC1 combination and discussed the creative opportunities of true remote control of off-camera lights on Wetpixel Live. (^[36])

In July 2022, Keldan shipped barn door light shapers for the 4X and 8X/XR series, featuring four hinged doors for shaping light output underwater. (^[37])

By late 2023, Keldan had introduced ambient-colored light models (the 8XR Ambient), emitting blue/cyan light directly to match ambient underwater light without requiring separate filters — a 18,000-lumen solution aimed at professional videographers. (^[38])

Product Lines

Compact Video Lights (4X, 8X, 8XR)

The 4X and 8X series are fixed-head, travel-friendly lights. The 8XR adds ultrasonic remote control compatibility. All feature Keldan’s signature dome lens and custom reflector for smooth, even light with gradual edge falloff, magnetic power switches, field-replaceable lithium-ion batteries with LED status indicators, and 200m depth ratings.

Modular Video Lights (8M)

The 8M series accepts interchangeable LED modules (Flux, CRI, Cyan, UV, Blue, Deep Red), allowing professionals to match lighting to specific shooting conditions. Previous-generation light owners can upgrade by purchasing new modules. (^[39])

High-Output Lights (18X, 24X, 18XR, 24XR)

Introduced in 2020, these cinema-grade lights deliver 30,000-35,000 lumens. The XR variants support the RC1 remote control system. (^[40])

Filters

• Spectrum filters — lens-mounted dichroic color correction filters in -2 and -4 stop variants, available for blue, green, and blue-green water types, plus dedicated versions for the Nauticam WWL-1 wet lens
• Ambient Light filters — light-mounted filters in 6m and 12m depth simulations that modify Keldan light output to match ambient underwater spectrum (^[41])

Accessories

• RC1 ultrasonic remote control (2020)
• Color Checker/grey card (2020)
• Barn doors for 4X/8X series (2022)
• Buoyancy collars (2020)
• Flotation brackets (2017)

Distribution

• Americas: Initially Nocturnal Lights (from 2010; ^[42]), later Nauticam USA (from 2014; ^[43]), and subsequently broader dealer networks including Reef Photo
• Asia-Pacific: Scubacam Singapore (2007; ^[44])
• Global: Direct dealer network via keldan.ch

Notable Users

Keldan lights have been used by professional underwater filmmakers and photographers including:

• Eric Cheng — tested Luna 8 LA-V lights in the Maldives with a 3D rig (^[45])
• Natalie Gibb — cave explorer who tested the 8XR and RC1 in cenotes, and used Keldan 8X lights for photogrammetry surveys (^[46])
• Erick Higuera — used Keldan 4X lights filming the documentary “Finisterra” (^[47])
• Hergen Spalink — used Keldan 8X CRI92 lights with Ambient and Spectrum filters shooting in Raja Ampat with the Z CAM E2 (^[48])

Community Discussion

Forum discussions reveal Keldan’s reputation among enthusiasts:

• Keldan 8X vs Big Blue 15000 vs Sola 15000 (22 replies) — Users compared high-output video lights; one Swiss-based user noted Keldan was “15min by car from my home” and praised the modular design and depth rating. (^[49])
• Keldan Ambient Lights vs Traditional Mixed Lighting (30 replies) — Discussion of Keldan’s ambient-colored light technology versus traditional white lights with filters, with users debating trade-offs for different diving environments. (^[50])

Wetpixel Live

Daniel Keller appeared as a guest on multiple Wetpixel Live episodes focused on underwater color science: Episode 74 (“Color Masterclass for Underwater Filmmakers and Photographers”), Episode 76 (“Color Rendering Index Primer”), Episode 81 (“Color Correction Filters”), and Episode 120 (“Off-Camera Remote Control”) (^[51], ^[52], ^[53], ^[54]). Two extra episodes provided detailed explanations of Keldan filter products: “KELDAN Ambient Light Filters Explained” and “KELDAN Spectrum Filters Explained” (^[55], ^[56]). Episode 243 featured cave explorer Natalie Gibb reviewing the Keldan 8XR lights and RC1 remote control (^[57]).

Trade Show Presence

Daniel Keller personally represented Keldan at trade shows throughout the company’s history, appearing regularly at DEMA Show (2006-2017), Boot Dusseldorf (2012, 2018), ADEX (2007, 2018, 2019), and the London Dive Show (2012). His hands-on presence and willingness to discuss engineering details in depth built the brand’s credibility with professionals and press. (^[58]) (^[59]) (^[60]) (^[61])

At Boot 2018, Keller and Wetpixel editor Adam Hanlon discussed collaborating on a guide to underwater color for imaging. (^[62])

Significance

Keldan occupies the high end of the underwater video light market. Their focus on CRI accuracy distinguishes them from competitors who emphasize raw lumen output. The company’s product evolution — from HID dive lights through high-CRI LEDs to modular systems with remote control and integrated filter solutions — reflects a consistent engineering philosophy centered on color quality.

The Spectrum and Ambient filter system represents a sophisticated approach to the fundamental challenge of mixed lighting underwater, enabling videographers to achieve color-balanced footage across entire frames rather than just within the reach of artificial light. The RC1 ultrasonic remote control opened creative possibilities for off-camera lighting setups previously impractical underwater.

Keldan’s transition from a niche HID dive light maker to a comprehensive video lighting ecosystem — encompassing multiple light families, modular LED modules, precision filters, remote control, color management tools, and light-shaping accessories — demonstrates sustained innovation over nearly two decades.

Product Timeline

• Pre-2006: Solaris HID dive lights — handheld and canister models, medical-grade white-light HID burners (^[63])
• 2006-11: Luna 8 WA and Solaris Tec 24 debut at DEMA 2006 (^[64])
• 2007-11: Luna 8 WA-V shown at DEMA 2007, 18-25W HID, 5 power levels (^[65])
• 2008-10: Luna 4 BS-V and updated Luna 8 WA-V shown at DEMA 2008 (^[66])
• 2009: Luna 8 LA-V LED video light shown at DEMA, first high-CRI LED (CRI 95) (^[67])
• 2010-03: Nocturnal Lights becomes Americas distributor (^[68])
• 2010-09: Luna 8 LA-V reviewed by Eric Cheng: 2100 lumens, CRI 95, $1,996 (^[69])
• 2011-01: Luna 8 LA-V CRI upgraded to 4000 lumens (^[70])
• 2011-07: Steve Douglas review confirms Flux (5000 lm) and CRI (3000 lm) variants (^[71])
• 2012-03: Luna 4V ships: 4000 lumens, $1,500 (^[72])
• 2014-09: Video 4X ships: 6000 lumens, CRI 82, $1,540; distribution moves to Nauticam USA (^[73])
• 2014-12: Video 8X ships: 10,000 lumens, $2,190 (^[74])
• 2014-12: Video 8M ships: modular system with 6 LED module types (^[75])
• 2016-05: Video 8X CRI (8000 lm, CRI 96), upgraded 8X Flux (12,000 lm), upgraded 4X (7000 lm) (^[76])
• 2017-04: Video 8X updated to 11,000 lumens CRI 92 (^[77])
• 2017-11: All lights upgraded at DEMA: 4X to 9000 lm, 8X to 15,000 lm, 18X to 25,000 lm, 24X to 30,000 lm; Spectrum gel filters introduced (^[78])
• 2017-12: Daniel Keller publishes filter effectiveness research video (^[79])
• 2019-02: Keldan releases animated filter tutorial videos (^[80])
• 2019-05: Massimo Franzese publishes Spectrum and Ambient filter review (^[81])
• 2020-03: Full 2020 range: 8X CRI to 15,000 lm, 8X Flux to 18,000 lm, 4X to 10,000 lm; 18X (30,000 lm) and 24X (35,000 lm) introduced (^[82])
• 2020-07: Color Checker card ships (^[83])
• 2020-10: Daniel Keller appears on Wetpixel Live color masterclass (^[84])
• 2020-12: RC1 ultrasonic remote control ships; Video 8M Flux upgraded to 11,000 lm (^[85])
• 2022-03: Video 8XR ships: 20,000 lumens, CRI 86, RC1 compatible (^[86])
• 2022-07: Barn door accessories ship for 4X and 8X/XR series (^[87])

References