Hogarthian
Configuration Guide.

You've decided to set up a Hogarthian configuration. You have a backplate, a wing, and a harness. Now what? This guide walks through every decision, from backplate position to D-ring placement, so your first Hogarthian setup is correct from the start — not after three dives of trial and error.

This is the most comprehensive free guide to Hogarthian configuration available online. Whether you're setting up your first backplate and wing or refining a system you've used for years, this covers everything: harness geometry, regulator routing, weighting, D-ring positions, and the practical first dives that make the system second nature.

What is the Hogarthian
configuration exactly?

The Hogarthian configuration is the standard equipment layout used in DIR diving. Named after William Hogarth Main, a founding figure in the DIR movement, it specifies not just what equipment to use, but precisely where each item goes and why. The core components are:

• Backplate (steel, aluminium, or soft) with a single-tank adapter or manifold
• Wing (internal-bladder, behind the diver)
• Webbing harness, fitted to the diver's body — no quick-release buckles
• Primary regulator on the right first stage, secondary on the left
• Long hose (150–200cm) on the primary second stage, arriving from the right side
• Inflator corrugated hose on the left shoulder
• Five D-rings in fixed positions: 2 chest, 1 left hip, 2 on the crotch strap
• Backup lights, SPG, and accessories clipped to correct D-rings

Every element of the configuration has a reason. Nothing is there for aesthetics. Understanding why each item is where it is makes the system genuinely intuitive — rather than a set of rules to memorise.

Step 1: Backplate selection
and what it means for your diving.

The backplate is the foundation of the entire system. Three materials are available, each with different buoyancy characteristics:

• Steel backplate (approx. 2 kg negative) — ideal for cold water diving with thick wetsuits or drysuits, where you need significant ballast from the plate itself. Steel divers typically need less belt weight. Not ideal for travel due to airline weight restrictions.
• Aluminium backplate (approx. neutral to slightly negative) — the most versatile choice. Near-neutral buoyancy in warm water with a 3mm suit. Works well in most recreational diving conditions without requiring excessive weight. Travel-friendly.
• Soft backplate (lightest option) — positively buoyant, requiring additional ballast weight, but the lightest and most packable configuration available. Purpose-built for travel where pack weight is the primary constraint.

For most recreational travel divers, an aluminium backplate is the correct starting point. It balances buoyancy, weight, and durability without the constraints of steel.

Step 2: Harness fitting
on land, before the water.

A correctly fitted Hogarthian harness has no quick-release buckles — this is a deliberate safety choice. Quick-release points are failure points. Losing the BCD and cylinder underwater can cause uncontrolled buoyancy changes. The fixed harness, adjusted once to fit the diver precisely, eliminates this risk entirely.

The key measurements:

• Shoulder strap length — with the backplate flat against your back, the shoulder straps should lie flat across your shoulders with no excess webbing bunching at the top.
• Crotch strap (sottocavallo) — this is the most commonly skipped element. It is not optional. Without it, any positive buoyancy causes the entire system to ride up your back at depth. It also hosts two D-rings (front and rear) and is essential when using an underwater scooter. Route it between your legs and adjust so it sits firmly against your body without restricting movement. The chest belt buckle must be positioned on the right side to prevent the crotch strap from accidentally opening it.
• Hip straps — snug enough that the backplate does not shift laterally. Not so tight that they dig in during a long dive.
• Chest strap — locks the shoulder straps together. Position it at mid-sternum.

Step 3: D-ring placement
five positions, five reasons.

The Hogarthian configuration uses exactly 5 D-rings: 2 on the chest, 1 on the left hip, and 2 on the crotch strap (front and rear). No more, no fewer. Every additional D-ring is a snagging risk and a drag point.

• Left chest D-ring — primary clip point for emergency backup lights. Both chest D-rings hold backup lights positioned under the armpits, secured under elastic bands on the harness. The diver must be able to switch on the light without unclipping it first — if the light is dropped accidentally while on, it is immediately visible.
• Right chest D-ring — second backup light, and secondary clip point for the primary regulator when not in use.
• Left hip D-ring (at waist height) — this is where the SPG (submersible pressure gauge) is clipped via a small bolt snap. The SPG hose comes from the left first stage and must be long enough for easy reading when unclipped, but not so long it extends beyond the diver's profile. The SMB and reel also clip here.
• Crotch strap front D-ring — attachment point for the underwater scooter (DPV) in use. No other items should be clipped here as it sits too low relative to the diver's profile.
• Crotch strap rear D-ring — attachment point for a spare scooter, stage cylinders, or other equipment close to the backplate.

The knife is positioned on the chest strap, slightly left of centre, reachable with both hands. Avoid hook-type knife attachments that make extraction difficult.

Step 4: Regulator routing
and the long hose.

Regulator configuration in the Hogarthian system is standardised for a critical reason: team gas sharing. The primary regulator is always mounted on the right first stage. This is not arbitrary — a contact against a cave wall or wreck structure rotates the right valve handle toward open, not closed. If the handle breaks, the regulator continues to function. The same contact on the left valve could close it, cutting off the primary air supply.

The standard routing:

• Primary second stage — on a long hose (150cm minimum, typically 200cm for recreational monobottle), arriving from the right side of the diver. This is the regulator you breathe from normally and donate in an emergency. The hose runs behind the right side of the wing and must not create a large loop at the front of the diver.
• Secondary second stage (backup) — on a short hose from the left first stage, held in position in front of the mouth by a collar. It must be reachable without using the hands. It does not pass the right chest D-ring and does not extend beyond the right shoulder.
• BCD inflator hose — from the right first stage (same as primary), arriving at the left shoulder. This means in a right first stage failure, the diver loses both the primary second stage and the inflator simultaneously — but retains the backup second stage from the left. If the inflator and backup second stage shared the same first stage, a single failure would leave the diver without both backup and inflation.
• SPG hose — from the left first stage, clipped to the left hip D-ring via bolt snap.

The corrugated inflator hose is kept in position on the left shoulder by a ring just above the left chest D-ring. This allows immediate location of the inflator without looking.

Step 5: Weighting.
Get it right first.

The goal of correct weighting in the Hogarthian system: neutrally buoyant at 3 metres depth with an almost empty cylinder at the end of the dive. This means at the start of the dive, with full cylinders, the diver will be slightly negative — by approximately the weight of the gas in the cylinder. According to UTD data, a fit diver can manage up to 2 kg of negativity using fins and lung control alone, without undue effort. The BCD is used at the start of the dive to compensate this initial negativity, not to carry permanent ballast.

Weight distribution matters as much as total weight. The best approach combines multiple systems:

• Weight belt (removable) — the preferred primary weight system because it can be ditched in an emergency. A diver must always be able to surface even with a failed BCD and full cylinders.
• V-weight or keel weight — fixed weight behind the cylinder that improves trim without affecting the removable weight system.
• Backplate weight — the steel backplate itself provides ballast. With an aluminium backplate, integrated weight pockets on the plate distribute weight centrally.

Never place all weight on the belt, and never rely entirely on fixed weight. The optimal solution uses all systems together. Over-weighting and compensating with a larger BCD is a common error — a BCD that is too large increases hydrodynamic drag, bulk, and entanglement risk without providing real benefit.

Step 6: Wing inflation
less than you think.

Because the wing is positioned behind you rather than around you, it requires significantly less gas to achieve buoyancy than a jacket BCD. New backplate and wing users consistently over-inflate. The correct approach: add the minimum gas needed to achieve neutral buoyancy, then use breathing to fine-tune. A diver with correct weighting should be able to maintain neutral buoyancy at depth using breath control alone, with the wing acting as a gross adjustment rather than a constant management task.

The wing volume should not be excessively large. The diver must be able to surface even if the BCD fails completely — with all equipment and full cylinders. A correctly weighted diver needs only the gas to compensate the weight of the gas at the start of the dive, not a large reserve of lift.

Instruments and
information tools.

The Hogarthian approach to dive instruments follows the same principle of minimalism and streamlining. A console combining multiple instruments is not recommended — it increases bulk, drag, and entanglement risk.

• SPG — clipped to the left hip D-ring via bolt snap on the SPG hose from the left first stage. No rubber cover on the hose (rubber covers hide corrosion and wear). No console.
• Compass — worn on the left wrist, like a watch.
• Depth gauge / dive computer — worn on the right wrist. This allows reading the compass with the left hand while managing the inflator with the left arm simultaneously.

Your first Hogarthian dives:
what to focus on.

• Dive 1: check harness fit and D-ring positions in shallow water. Don't worry about trim yet.
• Dive 2: focus on horizontal trim. If your legs sink, check your weight distribution.
• Dive 3: practice inflator use with eyes closed. Practice buoyancy control with breathing alone.
• Dive 4 onwards: practice frog kick and modified frog kick. The frog kick is the standard propulsion technique in DIR diving: knees and ankles bent slightly, feet and ankles brought together as in breaststroke. It produces no downward water movement, does not disturb silt, and is highly efficient. The helicopter turn (single-leg frog kick) allows 360° rotation without changing position.

Most divers report that by dive 5, the Hogarthian configuration feels completely natural. By dive 10, they cannot imagine diving any other way.

Common Hogarthian setup mistakes
and how to avoid them.

• Crotch strap not used — the single most common beginner error. Without it, the harness rides up at depth. The BCD shifts. Your trim suffers. The crotch strap is not optional.
• Over-weighted — moving from a jacket BCD to a backplate and wing almost always requires less weight. Check buoyancy at 3 metres with near-empty cylinders. Never compensate over-weighting with a larger BCD.
• Wrong D-ring count or positions — the standard is exactly 5 D-rings. Extra D-rings create drag and snagging risk. SPG goes on the left hip, not the chest.
• Primary regulator on the left first stage — always mount the primary on the right. Left-side contact with walls can close the left valve; right-side contact only opens it further.
• Long hose creating a loop at the front — the long hose must run behind the right side of the wing and not create a large forward loop. In a donation scenario it must deploy cleanly.
• Compass and computer on a console — wear instruments on your wrists. A console increases drag and entanglement risk with no benefit.
• Skipping the land check — always assemble and check on land. Confirm D-ring positions, hose routing, inflator function, and dump valve positions before entering the water.