A channel-depth label placed beside a ship can easily be mistaken for the space beneath its hull. If a marine project film discusses access, commission a section that identifies the water surface, vessel and bed separately. The audience should not have to guess which vertical interval a number measures.
The graphic is an explanatory aid, not a navigational assessment. Production should not calculate an available passage or imply that an illustrated vessel can safely use a channel.
Start every dimension at its proper reference
AMSA's under-keel-clearance information concerns the water beneath a vessel and the conditions relevant to assessing it. For a film, the key distinction is that water depth, vessel draught and remaining space are different quantities.
Ask the marine specialist to identify the approved references and terminology. Use separate dimension marks where necessary, keeping their endpoints visible. A single arrow from the water surface to the bed should not be relabelled clearance once a vessel appears in the frame.
If the section is schematic, avoid plausible-looking numbers that resemble a passage calculation. If it represents an actual project assessment, retain the approved condition, vessel identity and source. Do not derive hull depth from a side photograph.
A hypothetical harbour-project brief
A contractor wants to explain a completed marine-access package. The first animation lowers the seabed and immediately sends a large vessel through, implying that the visual change establishes navigational suitability.
The revised commission separates the construction scope from the specialist's approved access account. A labelled section explains the relevant intervals without inventing a safe transit. Any actual operational result is presented with its own evidence and authorised wording.
This gives a prospective infrastructure buyer useful context while respecting the boundary between delivered works and marine operations. A construction film need not become a simplified pilotage guide to explain why depth information mattered.
Keep changing conditions visible in the claim
A coastline view can locate the site, but it cannot replace the submerged reference geometry that this particular explanation requires. A fixed waterline can make the section look timeless. If the approved explanation depends on a particular water level or condition, keep that context attached to the image. Do not use one generic tide animation to imply that every other factor has been considered.
Likewise, a static ship model should not be presented as a complete account of vessel movement or dynamic clearance. The specialist decides what simplification is suitable; the filmmaker preserves its stated limits.
At review, trace each dimension from start to finish and ask what a viewer would call it. Check that short versions retain the waterline and bed references. Discuss the sequence with Live Images using the approved marine information, while leaving navigation, clearance assessment and operational permission with the responsible authorities and specialists.
Prepared with AI assistance for Live Images. Planning guidance is general; suitability and production scope must be agreed for your project.