Ikelite DS51 User manual

Product Registration
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DS51 TTL Strobe
Product Number 4044.1

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About this Product
Thank you for your purchase of Ikelite equipment. Please read this
instruction manual completely before attempting to operate or dive
with this product. Please visit ikelite.com to register your product
to receive information on any updates or notices pertaining to your
equipment.
Included in the Box
• DS51 strobe
• Diffuser # 0561.2
• Bulkhead cap # 9104.5
• 1” Ball Mount # 4081.4 (Strobes produced after October 1, 2016)
• Silicone lubricant 1cc tube # 0184.1
• 2 year manufacturer warranty
Specifications
• Weight ....................................................0.6kg (1.3 lbs.) with
batteries
• Energy Rating ........................................50 watt-sec.
• Coverage Angle ....................................70° (80° with diffuser)
• Widest Angle Lens ................................28mm SLR
• Guide Number (ISO 100) feet ...............56 surface, 28 underwater
• Guide Number (ISO 100) meters ..........17 surface, 9 underwater
• Firing Modes ..........................................TTL/Auto, Full, 5 fractional
powers
• Color Temperature 5700°K
• Power Source ........................................4 AA-cell alkaline, NiCad,
or NiMH

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• Flashes ..................................................200 full power
• Recycle Time..........................................3.5 seconds (full power)
• Depth Rating ..........................................90m (300 feet)
• CE - Compliant with applicable EU directives
• Complies with FCC part 15, subpart B, Section 15.109 for Class “B”
Products
Overview of DS51 Features
• Mode switch features TTL/auto and manual exposure settings.
• Battery compartment accommodates four AA batteries: alkaline,
NiCad, or NiMH.
• Ready light indicates when strobe has recycled.
• Diffuser provides softer lighting, wider coverage angle and reduces
strobe output by one f-stop.

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Important Notices
»To prevent salt build-up and sticking controls, submerge the
strobe in clean, freshwater. Operate the knobs several times
each while underwater to ush out any residue.
»Do not use cleaning agents, spray lubricants, Rain-X, or
other solvents on strobe. Use of an incompatible chemical
compound can damage the plastic and o-rings, and may result
in leaking.
»The DS51 bulkhead connector is not waterproof and must
be capped when not connected to a cord or sensor. Using a
DS51 underwater with the bulkhead connector uncapped or
unconnected will cause the strobe to ood.
»The strobe is factory sealed; do not disassemble. Disassembly
will void your Ikelite DS51 limited warranty.
»Do not continuously re the strobe more than 15 times above
water in rapid succession. If this does happen, allow the
strobe to cool down for at least 10 minutes.
»Lithium-ion batteries are NOT recommended

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Contents
Product Registration 1
About this Product 2
Included in the Box 2
Specications 2
Overview of DS51 Features 3
Important Notices 4
Getting to Know Your Strobe 7
Mounting the Strobe 8
Ikelite Arm/Mounting System 8
Attaching a Sync Connector 9
Battery Compartment 10
Opening the Compartment 10
Opening the Compartment 10
Changing the Batteries 10
Battery Compartment - continued 11
Closing the Compartment 11
Compartment Flooding 12
Strobe Ready Light 13
Ready Light with TTL Housing 13
Ready Light with Remote Optical Slave Converter #4403 13
Mode Switch 14
OFF position 14
TTL/Auto Exposure Position 15
Manual Exposure Position 15
Strobe Diffuser 16
Using the Diffuser 16
Diffuser Installation and Removal 16
Maintenance 17

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Post-Dive 17
Cleaning, Travel and Storage 18
Troubleshooting 18
Photos are over-exposed (too light) 18
Photos are under-exposed (too dark) 19
Strobe will not re 19
Strobe will not re when using sync cord 21
Strobe will not re when using an optical sensor 21
Ready light does not come on 22
Limited Warranty 22
Service and Repairs 23
Contact Us 24

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Getting to Know Your Strobe
ikelite
SUBSTROBE
DS
51
ikelite
Knob Battery Door Mode Switch
Strobe Ready Light
Waterproof
Bulkhead
Cap
Bulkhead
Connector
Flashtube
Mount

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Mounting the Strobe
Ikelite Arm/Mounting System
The DS51 will accept several Ikelite strobe arms and mounts on the
underside of the strobe body. A 1-inch Ball Mount Mark II is included
which will allow attachment to 1-inch diameter ball arms from Ikelite,
TLC, Ultralight, Nauticam, and others. For further information, please
visit ikelite.com.
51
ikelite
SUBSTROBE
DS
4080.05 Compact Ball Arm
4081.4 1-inch Ball Mount
Mark II (Included)

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Attaching a Sync Connector
»A bulkhead cap or waterproof connector must be attached
to the strobe for waterproof operation. Never submerge the
strobe without either a bulkhead cap or compatible waterproof
connector attached.
1. Remove the bulkhead cap.
2. Lightly lubricate the connector O-ring. We recommend using only
Ikelite silicone lubricant to eliminate the possibility of swelling due to
incompatible compounds.
3. Line up the pins and receptacles and insert the Sync Cord Plug into
the bulkhead. The plug should slide easily into the bulkhead. If you
feel resistance, do not force it. Remove the plug and check
alignment.
Sync Cord Plug
Connector O-ring
Bulkhead
Waterproof
Bulkhead Cap
4. Rotate the knurled retaining ring until snug on the housing
bulkhead. Do not use pliers or tools to tighten the retaining ring.

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Battery Compartment
Opening the Compartment
Always turn the strobe to OFF before opening the battery door located
at the back of the strobe. To access the battery compartment, rotate
the knob counter-clockwise several times and gently pull the door
off. Tilt the rear portion of the strobe down while removing the battery
door to eliminate the possibility of water droplets falling into the battery
compartment after a dive. Do not remove the knob from the battery
door. The battery compartment is sealed separately from the main
electronics. Do not disassemble the strobe. Disassembly will void your
Ikelite limited warranty.
Opening the Compartment
Be aware of the position of the o-ring around the perimeter of the
battery door. Keep the o-ring and sealing surfaces clean.
Lubricant is not necessary for proper sealing of the battery door o-ring.
To extend its life, you can lightly lubricate the exposed part of the
door’s o-ring before storing.
Changing the Batteries
Install four AA-cell batteries: alkaline, NiCad, or NiMH. Refer to the “+”
and “ – “ markings in the battery compartment to help properly install
the batteries. If the batteries are installed incorrectly, it may damage
the strobe’s electronics. Always carry spare batteries; weak batteries
cause many camera and strobe problems. It’s time to replace the
batteries when the ready light remains dark for 15 seconds or longer
after a ash.
Note: It is possible to buy bad “new” batteries, so check the voltage
output with a meter. Lithium-ion batteries are not recommended due
to their effect on the strobe’s recycle time and the batteries’ thermal
switch characteristics.