At the end of the specialty, a successful student deliverable should include:
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A raw bathymetric CSV or export preserved without edits.
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A cleaned and interpolated bathymetric surface or DEM with notes on any deleted false returns.
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A Dive 2 photogrammetry product or image set with scale-reference documentation.
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A Dive 3 orthomosaic or image set suitable for draping over the bathymetric surface, when conditions allow.
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Registration notes identifying control points, checkpoints, scale references, and any residual error or uncertainty.
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A short accuracy and limitations statement explaining what the map is good for and what it is not good for.
Common Failure Modes
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The surface float submerges and GPS lock is lost.
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Grid turns become arcs because the Surveyor's Pivot pause was skipped.
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Photo spacing is too wide, so the software cannot find enough overlap.
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Images are blurred, backscattered, overexposed, or shot from inconsistent distance.
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The scale bar is missing, too small, moved during capture, or visible in too few frames.
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Control points are all in a line, making the registration weak.
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Raw files are overwritten during cleaning or export.
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The team gets so focused on the camera, app, or float that gas, depth, NDL, or team awareness is neglected.
Sample Accuracy and Limitations Statement
Every map you publish needs one of these. You will produce a much better statement if you start from a template. Adapt the wording to your actual site, equipment, dataset, and the residuals you actually measured — do not just copy the numbers.
This map combines a bathymetric DEM from acoustic survey (Deeper Smart Sonar Max, narrow beam, towed at the surface) with a photogrammetric orthomosaic captured by underwater camera on a nadir-pointing parallel-strip pass. Datasets were registered using three control markers placed within the survey area, refined by surface alignment over a high-relief region. One independent checkpoint, not used in the fit, showed a residual of approximately 1.4 m horizontal. Absolute horizontal accuracy is estimated at ±5–8 m, limited primarily by consumer GPS on the surface float and float lag during turns. Vertical bathymetric resolution is sub-meter. Photogrammetric relative shape is estimated to be sub-meter where the scale bar was visible. The orthomosaic is suitable for diver orientation, site documentation, and change detection between surveys. It is not suitable for navigation, legal boundary work, salvage planning, archaeological excavation planning, or any safety-of-life application. Single-pass coverage in the northeast quadrant is documented as a single-pass limitation due to gas and visibility on Dive 3.
What makes this a good statement:
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It says what was measured, not just what was hoped for. The 1.4 m checkpoint residual is an actual number from an independent test.
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It names the dominant error sources by name (GPS, float lag) rather than waving at "some inaccuracy."
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It states approved uses and explicitly disclaims unsupported uses. Someone who reads this map knows whether they can use it for their purpose.
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It honestly documents the single-pass quadrant. Hiding that would be a small lie that quietly becomes a bigger problem if anyone tries to rely on the map for change detection later.