Stan Zaslavsky

5 Steps to Effective VCAT-Compliant Architectural Visualisations

Over the years, we have worked on numerous planning applications that required highly accurate photo-montage visualisations to allow the members of the VCAT tribunal to compare the impact of the proposed buildings on the streetscapes. Since then, we’ve become a VCAT-compliant render specialist and have created a number of proprietary processes to ensure technical accuracy in both our visualisations and statement of methodology.

There are two crucial elements to consider in VCAT photo-montages – technical accuracy and ‘intuitive’, or perception, accuracy. One can be defined by having an absolute technical accuracy to the modelling and the montage and the other has a lot more to do with how the members of the tribunal will feel about the images and whether they appear as a true representation of the proposed project. The intuitive aspect of the imagery is determined by how the ‘before’ photography was obtained and how it relates to human eyesight.

As visualisation software has improved, the expectation for high quality, process-driven 3D photo-montages for VCAT hearings is as high as ever. While technical accuracy is often assumed from reputable suppliers, intuitive accuracy has been under scrutiny a lot more, as different opinions exist about the focal length of the human eye. Although some believe that it’s in the order of 20-22mm, others feel that 50mm is much more representative of how we perceive the world around us.

Whatever idea you subscribe to, this article will discuss 5 key steps to effective 3D photo-montages for VCAT hearings, as well as explore the factors specific to them to ensure both technical and intuitive accuracy – and that the 3D images presented can stand up to cross-examination, if required.

Requirements for 3D Photo-montage Visualisations for VCAT Purposes

There are several key requirements for 3D photo-montages that have been prepared for a VCAT hearing.

Firstly, they must be circulated to all relevant parties for review no later than 10 business days prior to the hearing date – and this is an absolute must. Otherwise, the risk is that they will be completely disregarded by the tribunal members and potentially discredit the application.

Secondly, all VCAT-compliant 3D visualisations need to be in line with the rules set out from the decision of Austcorp Group Limited v Monash City Council [2006] VCAT 692. During that hearing, visual amenity evidence was thoroughly cross-examined and, ultimately, a set of requirements were established that must accompany all 3D photo-montages or visual impact assessment:

A written statement explaining the methodology used for the preparation of images, including:

  • The identity and qualifications of persons involved in the preparation of the images including data collection;
  • The name and version of the software programme(s) used to prepare the images;
  • The methodology used to collect relevant data (for example whether survey data has been obtained from topographical maps or fieldwork);
  • The camera brand and model including whether digital or SLR;
  • Camera lens size and the type and whether the camera was horizontal or tilted. If tilted, the angle should be stated;
  • Time of day and date of all relevant data (including when photographs were taken, survey information obtained and the like);
  • The height above ground level from which all images have been taken / would be viewed;
  • Details of any existing elements that have been reconstructed or modified (other than the proposal itself) such as modifications to existing vegetation, reinstatement of cross-overs and the like;
  • Any assumptions relied upon;
  • A plan showing the location from which all images have been prepared / would be viewed and the angle of view;
  • A photograph of the existing conditions;
  • A photo-montage of the proposal based on the same lens type/size and location as the photograph of the existing conditions (to enable direct comparisons) without the inclusion of any proposed landscaping;
  • A second photo-montage image showing the proposal with any proposed landscaping, including delineation of the proposed building outline in the background.


The points above are summarised in a Statement of Methodology report – some examples of which can be found online or, if you would like to see one of ours, feel free to get in touch for a sample.

We have found that the following 5 key steps always need to be absolutely spot on in order to achieve the right result and produce VCAT-compliant renders.

They are:

  • Photography
  • Camera Point Survey
  • 3D Model
  • Proposed Landscaping
  • Statement of Methodology

Step 1 – VCAT Photography

Aside from using professional photographers with the right equipment, there are a lot of nuances to getting the right kind of photography for the project.

This is where photography direction is very important and, if the principal needs to be involved in the hearing as an expert witness, then being present at the time of photography is essential to be able to make decisions on the best vantage points of the context.

Keys to VCAT-Compliant Photography

1.       Photography Basics

The photo should be taken with a 2-second timer delay – then the sensor has time to stabilise and not move as the trigger is pressed, thus giving the best quality photo possible.

2.       Mark out Camera points

Mark out position of camera point on the ground with an easily identifiable marker. I use a surveyor’s spray paint available from a local hardware shop to mark out ground points. It’s weather-proof, so if the surveyors need to come to survey the points in a day or so – the marks will still be there.

Then take photos of the locations with a second camera to be able to supply to surveyors, as required.

3.       GPS Locations / Timestamp details

In the Statement of Methodology, we are required to submit as much data about the photo as possible – most of this information can be obtained from the photo metadata. Some cameras either have a built-in GPS sensor and that information can be included, while other cameras allow an external GPS unit to be fitted to provide the details of the camera point location.

In our methodology process, we have removed the critical need to have this information as accurate as possible, by having a 3D point cloud of the context surveyed. Then the photo is matched in the 3D space to the actual point, as surveyed. It reverse engineers the camera position and increases the accuracy of photo-matching.

4.       Understand Tilt/Lens size

There has been a lot of discussion around the choice of the camera lens and how it relates to human eyesight. We’ve written about it extensively in this article, which has also been published in the VPELA magazine: Achieving Accuracy in View Align 3D Photo-montages for VCAT Appeals. In short, the wider the lens, the more the edges of the photo will be distorted – but more streetscape can be fitted in the shot. We prefer to stay to a lens above 20mm width, which is closer to human eyesight rather than some of the wider lenses.

However, if the case calls for it (ie: if the streetscape façade of the project is quite large and a wide lens needs to be used to fit everything in the shot) – the evaluation at VCAT is typically about seeing a ‘before’ and an ‘after’ scenario, and so, as long as this is described in the methodology statement, then that should be acceptable for the Tribunal members.

If the proposed building isn’t going to fit in the photo, you may need to tilt the camera vertically. Be aware that the more the camera is tilted up or down, the vertical lines are no longer straight and it may appear that the buildings in the photo are falling down – so the presentation of the images suffers and photo-matching of the 3D context to the photo becomes a bit trickier.

Step 2 – Camera Points Survey

One of the most important factors to ascertain is the location of the camera point relative to the proposed building. In 3D space, the virtual camera needs to then be positioned exactly in the same location, in order to be able to photo-match and place the proposed rendered out model in the photo.

There are a number of ways of obtaining the accurate camera point location. By far the best is to have a surveyor with a theodolite device able to produce a 3D point cloud together with a camera point location and the tripod location. We are then able to plot those points in 3D space and create objects that represent physical objects to assist with photo-matching. An effective instruction document and immediately visible marks for the camera point on site are the main keys to working with an external surveyor that may well need to be on site without the 3D studio member there at the same time.

Alternatively, if the budget for the project doesn’t allow for an additional surveyor – then a surveyor’s measuring wheel with one decimal point accuracy can be used to triangulate the location of the camera point to the nearest identifiable point on the survey. We use a Lufkin survey measuring wheel, which suffices for this purpose.

It is very important to obtain a CAD formatted survey of the site from the architect or client as you’ll need to draft the camera points accurately on the survey to be able to use it effectively in 3D software. Check the scale of the surveyor’s CAD file, as it is often in metres, rather than millimetres.

Step 3 – Model Accuracy & Fluidity

Once the photo-matching stage is completed, the model needs to be well organised and able to be adjusted swiftly, as required. Often, we are given minimal time to process the model / CAD information from the architects and have it ready for the rendering stage.

Whilst a lot of architects we work with utilise 3D architectural software, the models created in Sketchup, ArchiCAD or Revit 3D packages need a lot of work to convert across into a usable 3D Studio Max model. Quite often, those models have been developed from the concept stage and, although sufficient for preliminary visuals in council meetings, they are not enough for accurate 3D photo-montage visualisations.

Keys to Model Accuracy

1.       Massing Neighbouring Context

As well as matching up the camera through the survey or 3D data, it is very useful to also block model some of the neighbouring buildings. These can further confirm photo-matching –  especially if the subject site is a long distance away or obstructed.

2.       Model Conversion for Photo-Montage

Time pressure goes with the territory of 3D visualisation. This is especially pertinent when it comes to revising the architectural model and getting it ready for 3D rendering. Because the images need to be circulated within a specific time limit, being able to get working on the 3D model as soon as possible is one the most important keys to the success of the overall process.

Building Information Modelling (BIM) software, which allows architects to document straight from 3D models, has come a long way – however, for specialised processes, like 3D rendering, we still need to work a lot on the 3D objects from those programmes for the models to be useful.

We also utilise ArchiCAD in-house so we can natively work on the architectural files to simplify some of the models before they are converted. And if the architects have a change of heart and need to adjust anything? We can rapidly work in ArchiCAD first, before taking the models over to 3D Studio Max.

3.       Focus on Key Model Areas

As the renders are directed by the photographs, the camera angle can be used to infer which area of the model will be seen. We then focus all our attention on that area of the model to speed up production and delivery, especially if it’s a very large project.

Step 4 – Landscaping Accuracy & Species Selection

Delivering accurate proposed landscaping is extremely important to VCAT 3D photo-montage visualisations. Formal landscape plans often get scrutinised at tribunals for how the building is softened and blended into the neighbourhood character.

Our responsibility is then to show the proposed species in their most accurate form, based on height and maturity. With 3D Studio Max, we have unlimited flexibility in adjusting objects as required – however, when visualising projects for assessment, accuracy and care need to be exercised for how the planting is shown. Height at maturity, in some cases, may obscure the buildings too much – so most of the time trees are shown at around 70-80% of maturity and, if need be, in some cases, less, to show a medium point.

Keys to Landscape Accuracy

1.       Research & Placement of Plant Species

Using reference images found online, we either create custom 3D models or adjust existing library models of trees and plants to reflect the proposed landscaping on photo-montage renders. Accurate positioning of the plants – especially trees and large shrubs – is very important.

2.       Establish Maturity Level & Height of Tree Species

To have a clear picture of how much of the building is going to be obscured by proposed planting, we put a plan together, with town planners and landscape architects – how the proposed planting is going to be visualised. Showing a completely obscured proposed landscaping 3D montage may be questioned by the tribunal members as an over exaggerated representation of the proposal. Establish what the town planners would like to see in the montage, as these are very important tools to support the argument for the proposed development.

3.       Present the 3D Photo-montages With and Without Proposed Landscaping

In the practice note PNVCAT 2, there is a specific requirement to show two versions of the 3D montages – with and without proposed landscaping. The second part of this note also refers to showing an outlined building on top of the existing photograph – often planners ask us specifically not to produce this version of the montage, as it sometimes causes more confusion, rather than creating clarity about the proposal.

Step 5 – Statement of Methodology

Statement of Methodology report summarises the overall process and collates all the elements together, including the 3D photo-montages with their respective key inputs that were used to create them.

Keys to the Methodology Report

1.       Less is More

The report needs to be specific and concise and not waffle on. To be effective, barristers are trained to look out for anomalies and statements that look out of place. If a certain camera angle was decided on, then a brief explanation to this would suffice, rather than just making the statement about the decision without clarification, which could then raise a question about why it wasn’t explained.

Often, because there is so much information that parties on both sides need to process, the statement of methodology just needs to comply to the practice note and be specific to how the visuals were created.

2.       Ensure Key Elements of Process are Explained

The Statement of Methodology report is not an argumentative piece of information – it is there to concisely explain how specific steps were taken to arrive at the completed 3D photo-montages.

3.       Identify Key Consultants

In the process of creating the montages, we often take either instructions or get feedback from planners, architects and landscape designers. If they took part in the creation process, every one of them needs to be identified to ensure that, in case questions about the process come up, relevant consultants can be contacted to clarify, if necessary.

Effective 3D Photo-montages for VCAT Hearings are Essential

Accuracy and precision are keys that drive effective 3D photo-montages for VCAT hearings. And to support the visuals, a clearly defined and explained process is essential to the production. We are often told that when there are no questions from the opposition about the 3D renders, that’s a very positive sign and the montages have done their job.

This is exactly what we strive to achieve with our proprietary process that ultimately delivers a photo-realistic representation of the ‘after’ completed construction scenario to illustrate how the neighbourhood will be impacted.

To your development success,


Stan Zaslavsky

LREA, BEng (Mech with Honours) / BTech (Industrial Design), VPELA

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