DJI Terra to DJI Modify Workflow: Clean, Review and Deliver 3D Models in Canada

01Before opening DJI Modify: three gates

Start with the client’s decision, not the repair tool. A textured mesh for a stakeholder presentation, a model used to navigate an inspection, and a surface used in an engineering calculation do not have the same acceptance criteria. Write down the intended use, required format, coordinate reference system, units, target software and reviewer before editing.

Evidence gate: is the reconstruction defensible?

Confirm that imagery, project settings, control information, aerotriangulation and reconstruction outputs are available. Resolve unexplained offsets, incomplete coverage and failed project checks in Terra first. If a checkpoint or independent validation is required, retain its result separately from any visual cleanup record. A convincing texture cannot explain a coordinate error.

Coordinate gate: will the handoff stay in the right place?

Document horizontal and vertical references, units and any transformations applied upstream. Modify is not a coordinate-conversion stage. The v1.6 manual excludes mesh inputs with custom coordinate systems or seven-parameter transformations; the product notes also identify custom elevation limitations. Check a proposed coordinate workflow against the current documentation before committing editing time.

Compatibility gate: is this the supported mesh path?

DJI documents Terra v4.0.0 or later for this mesh workflow, with Work with DJI Modify enabled to generate the editable output. The current manual also excludes models reconstructed from photos without image POS data. A generic OBJ or PLY from another application is not proof that all Modify mesh tools will work.

Check the workstation and authentication path as well. DJI documents Windows, an NVIDIA GPU and substantial RAM/VRAM requirements. An offline Terra licence does not establish that Modify can be used offline. Test a representative block on the intended machine before allocating a large editing job.

02A controlled Terra-to-Modify handoff

Before creating the linked editing project, preserve the raw imagery, Terra project, reconstruction results and QA evidence under your organization’s backup policy. Keep an untouched deliverable that can be reopened. This independent preservation is different from renaming or copying folders after Modify has established its links.

Generate the right editable output

Enable Work with DJI Modify in the supported Terra reconstruction workflow. The v1.6 manual describes generating a DMEP editable-project file and opening Modify from Terra after reconstruction. Existing compatible Terra projects can generate the required outputs without repeating the entire reconstruction process. Follow the current Terra instructions rather than treating every missing DMEP as a reason to reprocess all source data.

If creating a project manually, check the requested model and aerotriangulation inputs. The manual identifies B3DM, PLY, AT XML and undistorted-image inputs in the mesh project setup. Undistorted imagery matters when projecting texture onto repairs. Verify access to these supporting files on the editing workstation, not just the presence of a model that initially opens.

Protect linked names and paths

Once linked, leave the Terra task name and modelling-result folders in their established locations. DJI warns that moving, copying or renaming those linked results can make files inaccessible. Do not tidy the working directory, rename the Terra task for a client, or delete the source project as a routine disk-cleanup step. The manual warns that deleting the Terra project can also delete its linked Modify project.

Record Terra and Modify versions, the active workspace path, backup location and project owner. On a second machine, perform an import-and-open check before the original workspace is retired. If dependencies are missing, stop and restore the documented structure; repeatedly moving folders makes diagnosis harder.

03Build a defect register before batch editing

Review the model in both overview and close-up views. Give each questionable area a block reference, a screenshot and a decision: keep, repair for presentation, or return to reconstruction/capture. Record what the source images show and which intended use is affected. This prevents “select all” from becoming an undocumented editorial decision about the site.

The register below is a planning template. On small screens, scroll horizontally to read all three columns.

For example, a vehicle can legitimately be absent from a cleaned public presentation while remaining important in the original construction record. Those are different deliverables, not competing versions of the truth. Agree on the distinction with the client before removing it.

04Repair conservatively, one defect type at a time

Use a small, representative area to establish the editing standard. Review the result, agree what must remain visible and then work through the register. Batch repair is useful after the selection rules are understood, not before. Save at deliberate milestones and keep an independent record of consequential edits.

Choose the editing level and blocks deliberately

The v1.6 manual describes high-quality PLY and low-quality B3DM mesh levels. Local flattening, texture repair and hole filling use enabled high-quality blocks; broad floating-part and water work follow the lower-quality path. These are editing representations of the same project, not interchangeable quality labels for every export extension.

Load only the blocks needed for the current repair. If RAM or VRAM runs out, unload high-quality blocks, save explicitly and reopen as needed. Check the current DJI block-splitting guidance before processing another large job. Hiding a block and unloading its high-quality representation are different controls; inspect which blocks are actually included in the operation.

Floating parts: review several views

DJI’s FAQ explains that floating-part removal depends on what is visible in the current view. After one pass, zoom and inspect again as blocks update. Remove known artifacts while deselecting objects that should remain. Pay particular attention to thin structures, isolated assets and site-edge objects that could be mistakenly treated as noise.

Flattening: select the right surface, not just the vehicle

Use an appropriate near-top-down view for vehicle recognition and inspect the selected boundary manually. Preserve curbs, ramps, steps and nearby structures. The v1.6 manual includes flattening direction and height controls, including custom height. Setting a height still does not verify that it matches the measured ground, preserves the correct slope, or meets an engineering tolerance.

Inspect every block boundary crossed by the repair. A locally convincing surface can leave a seam or height discontinuity at its edge. Compare it with the untouched model and neighbouring geometry, and record any area that is acceptable for presentation but excluded from downstream measurement.

Hole filling: identify the gap before closing it

A mesh opening may be incomplete reconstruction, an actual doorway, an underpass or an occluded surface. Inspect the source evidence before filling it. For a permitted visual patch, check the selected perimeter and resulting surface from multiple angles. Confirm that the repair did not bridge separate objects or cover a real opening.

If the result receives an unsuitable or solid-colour texture, check access to the supporting aerial/undistorted imagery and aerotriangulation files before painting over the symptom. A visually improved patch remains edited geometry. If that wall or surface is central to the client’s task, disclose the gap or return for better source coverage.

Texture and water repairs: review what the tool changes

Erase and Clone can improve appearance, but copied pixels are not a new observation. Do not clone a road marking, crack, façade feature or asset label into a location where the source does not show it. Keep evidence-bearing details in the original record and describe presentation edits separately.

For water, review the polygon, height and mesh-deletion range before committing the operation. The manual describes removal of mesh below the water surface and within an adjustable range above it. Inspect bridges, quay edges and nearby assets after rendering. A smooth water plane is not a measurement of the lakebed or proof of a surveyed water level.

05What cleanup can and cannot prove

Cleanup can make a model clearer, easier to navigate and more suitable for a defined presentation. It can also remove or change information. The central release question is therefore not “does it look better?” but “can the recipient distinguish captured evidence from the edited representation?”

Keep the untouched master as the reference for the captured condition. Link each substantive repair to the defect register and identify areas where geometry, texture or an asset’s presence has changed. For decision-critical surfaces, agree whether the original evidence is sufficient, whether an independent check is needed, or whether the area must remain excluded.

For Canadian projects requiring professional survey interpretation or sign-off, involve the responsible qualified professional in the acceptance criteria. Software editing alone is not that sign-off. Avoid blanket “survey-grade,” “engineering-ready” or accuracy-improvement claims unless the specific deliverable has supporting validation.

06Render, export and test the client’s actual viewer

Save the editing state explicitly before rendering. The v1.6 manual describes a pre-render history backup, but not an automatic backup of the post-render version. Directly closing or exiting Modify is not a reliable autosave strategy. Name important saved versions and retain an independent backup before irreversible workspace cleanup.

Render synchronizes edits between model levels. Inspect the rendered result again rather than approving only the editing view. Check repaired areas, block seams, textures and objects near selections. If the rendered result differs from the intended repair, resolve that discrepancy before exporting or sharing.

Confirm formats against the installed version

The v1.6 manual lists B3DM, OSGB, PLY, OBJ, S3MB and I3S in its mesh export section. It also documents format-specific merging/simplification controls, with FBX appearing in those controls and in the release notes. The FAQ’s shorter default-format list is not a complete substitute for version-specific documentation. Confirm the exact option in your installed build and test it with the client’s software.

Merging blocks can simplify file management. Reducing triangles and texture can improve loading, but it changes the derivative delivered to the recipient. Retain the full-detail reference and record the simplification settings. Test thin objects, façade detail and texture readability before approving a reduced export; a smaller file is not automatically the better operational model.

Use a short acceptance test

1. Open: load the delivered files in the agreed viewer, on a machine outside the editing workspace.
2. Completeness: confirm the expected blocks, textures and supporting files are included.
3. Position: compare a known reference location and documented CRS/units with the expected project position.
4. Edited areas: revisit register entries at overview and close-up scale, including seams.
5. Usability: confirm the recipient can navigate and use the model for its stated purpose.

Record viewer/version, export settings, reviewer, date and unresolved limitations. Agree project-specific thresholds rather than inventing a universal loading-time or accuracy target. A successful Export message proves that files were produced, not that the client’s downstream workflow has accepted them.

07Decide whether cloud sharing is allowed in Canada

Separate authentication connectivity from permission to upload a model. The fact that software needs a network licence does not mean the client has authorized cloud distribution of site data. Decide the sharing route before creating a public-facing link.

DJI’s current FAQ states that models uploaded from outside mainland China are stored on US servers and that coordinate information is removed before upload. Under that regional rule, a Canadian upload would use US storage. Coordinate removal does not establish anonymity: geometry, textures, signs and recognizable buildings may still identify the site.

Ask the client’s data owner to approve the destination, recipients, access controls, sharing period and any applicable procurement or cross-border restrictions. Municipal, utility and sensitive-infrastructure projects may have contractual requirements beyond the software’s defaults. This guide does not determine legal compliance for a particular organization.

If cloud sharing is approved, verify the available permissions and expiry options in the current version, test access as the intended recipient and record who owns the link. The manual describes sharing permissions, validity period and cloud capacity controls. A link is a viewing route, not the sole archive, editable project or proof that a file has been accepted.

If upload is not approved, use the agreed local/exported handoff and client-controlled transfer method. Do not upload a confidential sample just to test convenience. The broader municipal GIS workflow resource provides context for downstream data ownership and GIS-ready delivery.

08A client handoff package that survives review

Deliver more than a model and a link. The recipient should know which file represents the untouched reconstruction, which is cleaned, what changed and what has not been checked. The following checklist is a recommended editorial control, not a mandatory DJI packing list.

• Untouched master and evidence locationIdentify the reference output and the retained source/QA record. State who maintains it and how the client can request access, subject to the project’s data rules.
• Clearly named cleaned derivativeUse a revision and purpose label, such as site-model-presentation-r02. Keep original and edited deliverables distinguishable; do not silently overwrite the reference.
• Format, coordinates and settingsList export format, horizontal/vertical reference, units, software versions and any merging or simplification. Include required companion textures and viewer instructions.
• Edit registerFor each substantive change, record block/location, symptom, action, reason, evidence reference, operator, reviewer and date. Include before/after views where they clarify the decision.
• QA, limitations and exclusionsState what was tested, what remains approximate, which areas were not checked and which uses are excluded. Do not hide incomplete source coverage behind a repaired surface.
• Sharing and acceptance recordRecord the approved transfer route, any cloud use, recipients and access period, plus the client’s viewer test and acceptance outcome.

A small example of a useful edit record

Illustrative example, not a customer case: “Block B07, courtyard vehicle area: vehicle mesh removed from presentation derivative; source condition retained in untouched master. Evidence: capture image reference and before/after views. Boundary/texture checked by reviewer; repaired area excluded from surface measurements. Approval status and date recorded in the project register.”

The valuable part is the decision trail, not the amount of paperwork. If a reviewer later asks why an object disappeared, the team should be able to answer without reconstructing the operator’s memory. Release only when unresolved issues are either corrected or explicitly accepted for the stated use.

09Choose the software purchase path after defining the job

Start with representative source data, the required mesh output, workstation and client handoff. Then confirm the edition, term, activation/network requirements and exact features required. A Terra licence name should not be treated as proof that Modify access is included.

SpeedyDrone’s current DJI Terra collection includes the following two purchase paths. These links identify the live listings; they are not a claim that the editions have identical entitlements or that either includes Modify.

For Modify licensing or an unclear software configuration, contact SpeedyDrone with the installed versions, source/output type and intended delivery. For a broader acquisition-to-delivery plan, use the Surveying and Mapping Solutions page or the DJI Enterprise hub. Do not buy a new aircraft to solve a post-processing issue until the source of the problem is understood.