Week 1 – The Age of the Image and the Trend of the Lens

What was covered in the lecture:

What do you consider to be a Current Trend of VFX? Talk about possible meanings – what do you think a trend is?

A current trend in VFX is a pattern or direction in which the industry is evolving, based on recent innovations, technology, and audience demand. Trends often reflect what is gaining traction, either because it’s solving a problem, creating new opportunities, or reshaping how filmmakers tell stories. In VFX, these trends tend to emerge as technology advances and filmmakers seek more efficient or immersive ways to bring their visions to life.
For instance, de-aging is a trend because it taps into a growing demand to seamlessly alter an actor’s age without the need for extensive makeup or new casting. It’s being used in major films and series, making it a technique that’s gaining relevance.
A trend can also hint at the future. For example, real-time rendering is pushing VFX to become faster and more interactive. It’s reshaping the industry by making it possible to make real-time decisions on-set, blending virtual elements into live-action scenes on the spot.

Impact of Lenses on Cinematography:

Lenses play a crucial role in how a scene is captured and presented, influencing not only the visual quality but also the emotional impact of a shot. Different lenses affect focus, depth of field, perspective, and how the audience perceives the space and characters within a scene. Directors and cinematographers use lenses creatively to convey mood, tension, and storytelling.

Examples of Lenses Used for Dramatic Effect:

1. Dolly Zoom (Vertigo Effect): One of the most famous uses of lens manipulation is the dolly zoom, where the camera moves forward (or backward) while zooming in the opposite direction. This creates a warping effect where the subject remains the same size, but the background appears to stretch or compress. In Harry Potter and the Prisoner of Azkaban (2004) when Harry experiences a moment of dread at the sight of the Dementors near the lake. The effect amplifies his fear and isolation.

2. Wide-Angle Lenses: Wide-angle lenses exaggerate space and perspective, making objects in the foreground appear larger while creating a sense of vastness in the background. Directors use these to emphasize isolation or tension between characters, as seen in The Boys (2019), particularly during scenes where Homelander’s dominance is portrayed, such as when he’s flying or standing over his enemies, emphasizing his power.

3. Telephoto Lenses: Telephoto lenses compress depth, making objects at different distances appear closer together. This can create a sense of claustrophobia or emotional closeness. In Game of Thrones, telephoto shots are utilized during intense battles to emphasize the chaos and confusion among characters, particularly in the Battle of the Bastards.

Lens Effects Replicated in Visual Effects Context:
In visual effects (VFX), similar principles are applied digitally to enhance or replicate these dramatic lens effects:
1. Digital Dolly Zoom: The dolly zoom effect can now be created digitally in VFX, allowing filmmakers to simulate the same dramatic feeling without needing precise in-camera movements. In Avengers: Infinity War (2018), a digital dolly zoom is subtly used when Thanos retrieves the Soul Stone, intensifying the gravity of the moment as Gamora’s sacrifice becomes clear.

2. Simulated Depth of Field: In scenes with heavy VFX, artificial depth of field is often added to digital shots to mimic the way a lens naturally blurs the background, giving focus to the subject. In House of the Dragon, a good example of simulated depth of field happens during the scene where Rhaenyra Targaryen and Alicent Hightower. The background is blurred, which helps to highlight the strong emotions between the two characters. This technique shows the rising tension in their relationship, allowing viewers to really connect with their expressions and the seriousness of the situation, while also showing the impressive setting around them.

Also, they use artificial depth of field to make the background blurry and focus on the main subject in dragon scenes, where it helps show their size and impact.

3. Virtual Lenses in 3D Software: Filmmakers use virtual lenses in 3D programs to imitate how cameras work. They can add effects like blur and light flares to make digital scenes look more real. In House of the Dragon, during the big dragon battles, virtual lenses help create a sense of realism and make the action more exciting.

The Workshop Activity:
Can we spot any current trends of VFX?
1. De-aging: A visual effects technique used to make an actor or actress look younger, especially for flashback.
Avengers Endgame –

Captain Marvel –

Marvel –
With the complicated timeline of the MCU, there are a lot of flashbacks. Instead of using new actors, the original stars can travel back in time with the magic of technology to portray their characters at a younger age.

The Weekly Activity:

‘A New Reality‘ (2020) Age of the Image, Series 1, episode 1. BBC 4, Television, 24 February, 21:00.

In The Age of the Image, Dr. Fox explores how we live in a visually dominated era where images have an high influence on our daily lives, culture, and even how we see reality. He emphasizes that unlike past centuries that were defined by philosophy or novels, today’s world is defined by an overwhelming creation and consumption of images, due to advanced technologicies like smartphones and digital media. The availability of images has not only changed what we see but also how we interpret and interact with the world.

Dr. Fox discusses the growth of new image-making techniques, which were inspired by scientific developments such as Einstein’s theory of relativity, which suggested that space and time are flexible. This idea is represented in the work of artists like Salvador Dali, whose famous soft clocks in The Persistence of Memory are supposed to represent the bending of time, illustrating Einstein’s ideas. Dali’s art, alongside the rise of film and photography, created a visual language that is capable of manipulating time—freezing or stretching it in ways that the human eye cannot detect. The manipulation of time and space in his art reflects scientific advances such as high speed photography and nuclear images, which expose what was once hidden from the naked eye.

Fox also discusses on how visual culture has grown into the “age of the lens,” in which cameras not only catch but also shape our realities. This era has enabled people to create and edit images. He questions the legitimacy of these photos, wondering if we can actually trust what we see in a time based on digital editing, deepfakes, and visual illusions.

In conclusion, Dr. Fox suggests that today’s era is deeply influenced by both the artistic and scientific manipulation of images, comparing how we now experience time, space, and reality itself through the lens of modern technology.

Week 2 – The Photographic Truth Claim: Can we believe what we see?

What was covered in the lecture:
Allegory of the Cave – Video
The Allegory of the Cave is a famous philosophical theory by Plato that explains how people mistake shadows for reality. In the story, prisoners are chained in a cave, only seeing shadows on the wall, believing these to be the real world. The allegory shows how images are signs and not the actual thing, with everything tied to image projection—mere phantoms. It represents the journey of enlightenment, where most people live in the shadows until they uncover true knowledge.
This relates to the Socratic method, where learning new truths can be overwhelming at first.

Photographs as Indexical signs
Peirce’s definition of “index” was a sign that shows evidence for the existence of what it refers to e.g. a footprint or a crack. In terms of photography, indexicality refers to the fact that a photograph is created by the direct action of light on a photosensitive surface.
They often called reference object.

What is Semiotics?
Semiotics is the study of signs and symbols and how they are used to communicate meaning. It explores how words, images, and other symbols represent ideas, concepts, or objects in society, helping us understand how meaning is constructed and interpreted.
For example, in advertising, a red rose often symbolises love or romance. The rose itself is just a flower, but through semiotics, it has come to represent deeper meanings in our culture, such as passion or affection.

Perceptual Realism
Refers to the way visual media, like films or photos, try to mimic the way we naturally perceive the world. By using techniques that match our real-life visual experiences, it creates a sense of realism that makes viewers feel like what they are seeing is genuine.
In movies like The Matrix, visual effects are designed to look as natural as possible, even when showing impossible things like slow-motion bullets. This helps create a world that feels real to the audience, even though the events are fictional.

Photographic truth claim
The photographic truth claim is the assumption that photographs reflect reality as it is. Because photos are captured by a camera, people often believe they are an objective record of events. However, photographs can be edited or framed in ways that shape how we interpret them, meaning they don’t always show the full truth.
News photos are often considered factual representations of real events. For example, an image of a protest might be seen as proof of the event’s occurrence, but depending on how it’s framed (focusing on the crowd or an isolated act of violence), it could give different impressions of what happened.

The Workshop Activity:
Examples where image becomes more reality and reality becomes more image:
CGI ads:

Environment Building:

The impact of VFX on Photographic Truth:
Visual effects have a strong impact on the way we perceive images. It challenges the traditional photographic truth claim, which assumes that images captured by a camera are direct representations of reality.
Using semiotic concepts such as indexicality (the link between the image and reality) and iconicity (how much the image resembles reality), VFX challenges this traditional understanding by creating images that blend reality with digital fabrications. While photographs were once considered to have a direct connection to the real world, VFX blurs the line between the real and the artificial, making it harder for viewers to distinguish truth from fiction.

Semiotic Analysis:
– Indexicality: In House of the Dragon/Game of Thrones , many scenes involve characters interacting with fully CGI dragons. While the actors and some sets are real, the dragons and some of the environments are completely made using VFX. This breaks the direct connection between the image and the physical world, as the dragons don’t exist in reality.
– Iconicity: The CGI dragons designed to look like real animals with realistic textures, movement, and lighting effects, making them look real. Although the audience knows that dragons are fictional creatures, their realistic appearance and interaction with real actors makes it hard to tell that they are not real.
– Photographic Truth: The show does not claim to show historical reality, but it builds a world where viewers are drawn into a believable narrative. The presence of dragons and other digital elements challenges the photographic truth claim by mixing real and digital, making it difficult to see where reality ends and fiction begins, even in a fantasy setting.

How VFX Challenges Photographic Truth in House of the Dragon/Games of Thrones:
VFX in House of the Dragon/Games of Thrones combine digital creatures like dragons into scenes with real actors and environments. This challenges the idea that images are always a true representation of reality, as the scenes show a mix of real and fake. The dragons appear real enough to make audiences momentarily forget they are watching CGI.

Do Viewers Accept These Images as “Real”?
Although viewers know that dragons are not real, they still accept these digital creatures as part of the story. The detailed VFX allows audiences to believe in the dragons while watching. The dragons behave like real animals, which makes their actions easier to understand and relate to. This connection helps viewers see them as real, even though they are made with VFX. This shows how VFX can create a compelling and believable image that challenges traditional concepts of photographic truth, despite being entirely CGI.

The Weekly Activity:
What do you think is meant by the theory: The Photographic Truth-Claim?
The Photographic Truth-Claim is the idea that photographs provide an accurate and objective representation of reality. This belief comes because photos are created through a mechanical process leading people to assume that what they see in a photo is exactly what happened. This assumption creates trust in photographs as true proof of reality. People feel that because a photograph captures a moment directly from the world so it must be true.

However, even when a photo captures true reality, how we interpret it can still be shaped. The photographer influences the narrative through choices like angle, framing, lighting, and lenses. Tom Gunning in his article “What’s the Point of an Index? Or, Faking Photographs”, explains that both traditional and digital photography involve choices and manipulation that affect the final image. Although photos have an indexical link to reality, it does not guarantee truth. Manipulations like editing can change how reality is presented, making the photographic truth claim less reliable.

Visual effects greatly impact how we interpret images and challenge the photographic truth claim. VFX uses semiotic concepts like indexicality (the link between the image and reality) and iconicity (how closely the image resembles reality) to blend real-world elements with digital fabrications, making it hard to tell real from fake. For example, in “House of the Dragon”, CGI dragons interacting with real actors break the indexical link, as dragons don’t exist. However, the iconic nature of the dragons, which were created with realistic textures, movements, and lighting, gives them a real and convincing appearance. The show blends digital creatures and real actors so smoothly that viewers forget for a moment that they’re watching CGI and accept the images as real.

In summary, the Photographic Truth Claim is the belief that photographs capture true reality. I believe this theory is wrong because photographs can be manipulated and modern technologies like VFX further blur the line between reality and fake.

Week 3 – Faking Photographs: Image manipulation and computer collage

What was covered in the lecture:
A Trend of Fakery and Hoaxes
Fakery and Hoaxes usually involve creating fake images to trick people. In the past, before digital technology, people used non-digital photographs in hoaxes. They would stage photos or use tricks with cameras to make things look real, even though they weren’t. With digital editing today, it’s even easier to make fake images. People can use software to change pictures, making them look convincing even though they’ve been altered.
In politics, fake images are sometimes used to create false stories or change how people feel about a person or event. This trend has grown with the internet, as these fake pictures can spread fast.
Conspiracy theories:
Conspiracy theories often use these fake or hoax photos to make their stories seem real. When people see a picture, even if it’s fake, they might believe the conspiracy is true because it looks convincing.

The Workshop Activity:
Collect four famous faked photographs (non-digital) that were later proven to be fake.
The use of doctored photographs to achieve political ends:
In this 1937 publicity photograph taken at filmmaker Leni Riefenstahl’s villa in Berlin, Nazi propaganda minister, Joseph Goebbels, can be seen standing beside Adolf Hitler.
Experts believe that Goebbels was removed from the published photograph to dampen rumors he was having an affair with Riefenstahl.

Stalin used a large group of photo retouchers to cut his enemies out of supposedly documentary photographs. One such erasure was Nikola Yezhov, a secret police official who oversaw Stalin’s purges.
Stalin knew the value of photographs in both the historical record and his use of mass media to influence the Soviet Union, they often disappeared from photos too.
Conspiracy theories:
Fairy Hoax and Loch Ness Monster

What techniques were used to fake these imaged?
Retouching: Artists would physically alter the negatives or prints of photographs using tools like brushes and inks to carefully erase or paint over unwanted details.
Airbrushing: This involved using an airbrush tool to blend parts of the photo, effectively smoothing over areas where a person or object had been removed.
Cropping: Sometimes parts of the photo were simply cut out or cropped to remove the subject.
Double Exposure: Another technique involved overlaying multiple negatives to combine or remove elements from an image.

Collect four famous faked digital photographs digital that were later proven to be fake
A photo of a lion strapped onto a machine in order to make the iconic MGM intro of a lion roaring is actually a photo of a lion being diagnosed at the vet’s office.

This photo of an explosion was actually taken 7 years after Einstein’s death
Politics:

Events:

Collect four historic examples where visual effects shots were faked to look like real documentary or TV footage:
Chernobyl (HBO):


The Crown (Netflix):

The Irishman:

VFX were used to recreate historical New York City and various environments from the 1950s to 1970s
The Queen’s Gambit (Netflix): 00:48-00:58

this show uses VFX to recreate the look and feel of various cities in those decades, including New York, Paris, and Moscow. The environments were digitally altered to match historical footage of these cities.
VFX by Chicken Bine FX

How does the use of visual effects contribute to the story?
The use of VFX in movies and TV shows that recreate old environments helps make the story feel more real and believable. By recreating historical places and events it allows the audience to be fully immersed in the time period without distractions. It brings places that no longer exist or have changed a lot over time back to life, so viewers can feel like they are actually there.

For example, in “The Crown” and “Chernobyl,” VFX makes it possible to recreate 1940s London and the Chernobyl disaster site in a way that looks real and matches old footage. This makes the audience feel like they’re witnessing history as it happened, which helps tell the story more effectively. VFX allows filmmakers to show events or environments that are difficult to film today, making the story richer and more authentic.

The Weekly Activity:
Find two composite VFX shots from a movie or TV show. Try to pick ones that are not obvious VFX shots. Period dramas or more subtle scenes can be great choices.

A composite in visual effects VFX means combining different visual elements from different sources into one smooth realistic scene. These elements could include live action footage, CGI, and practical effects like props or fake smoke. Compositing is used to create environments or effects that would be hard and sometimes impossible to film in real life and blending them together in a way that looks natural and convincing.

In The Queen’s Gambit, many scenes use VFX compositing to create realistic environments that combine real actors and objects with CGI. One example is the use of set extensions with green screen to expand the look of streets and buildings. While the actors and part of the building and street were filmed on set, the rest of the environment, such as additional streets and background elements, was added digitally.

In another scene, green screen was used for background compositing when actors were filmed inside a car or standing on a balcony. The actors and parts of the set were filmed live, while the surrounding environment, such as buildings, skylines and other objects, was created using CGI.
 
Both examples required strong attention to optics, perspective, and framing to ensure that the CGI extensions and backgrounds followed the same angles, lighting, and shadows as the real world elements. Proper alignment of lighting and reflections was important to make the scene feel realistic, blending the real footage with digital effects.
Another example involves adding CGI elements, like snow, in a winter scene. The house and trees were filmed practically, but the snow and stairs were added digitally, making the scene look like a real winter setting. The snow followed the shape of the roof and ground naturally, and the lighting and shadows were adjusted to make it look convincing.

In all these examples, VFX compositing was essential in expanding and improving the real world footage, and visual composition techniques, such as the rule of thirds, helped frame the shots in a natural way. This allowed the VFX to blend smoothly with the live-action parts, making the final scene look realistic.

Chicken Bone FX “The Queen’s Gambit” VFX Breakdown

Week 4 – Trends of Photorealism

What was covered in the lecture:
What is Photorealism?
Photorealism is an art style where the artist creates a painting or image that looks as realistic as a photograph. Artists use detailed techniques to capture the subject with a high level of precision, including shadows, reflections, and textures, so the final result appears almost identical to a photo.
Trend of Photorealism:
Recently photorealism has become popular in digital media, with advancements in 3D modeling, computer graphics, and CGI. Artists now use software to create highly realistic images that are used in movies, video games, and advertising. The trend is moving towards creating digital environments and characters that look incredibly real so its really hard to tell what’s real and what is fake.
Richard Estes:
Richard Estes is an American artist, best known for his photorealist paintings. The paintings generally consist of reflective, clean, and inanimate city and geometric landscapes.

The Workshop Activity:

Photorealism in visual effects refers to creating digital images or scenes that are so realistic they look like actual live action footage. VFX artists achieve this by replicating real world details, making it hard to tell the difference between what’s real and what’s CGI.
Key Elements:
– Lighting: Accurate light sources and natural light behaviour.
Example: The dragons are in the shadow because the angle of the camera and the sun    
– Texture: Realistic surfaces/skin with fine details.
Example: Castle texture, Wall texture.


– Shadows: Correct placement and depth of shadows based on light sources.
Example: The dragons are in the shadow. The soft shadows reflected on the sand because of the cloudy environment.

– Reflections: Proper reflection of objects in water or glass.
Example: A car’s body reflecting the surroundings.

– Motion: Natural movement that mirrors real-life physics.
Example: The dragon flies/diving with realistic gravity and wind effects.

– Proper scale and proportions – of objects and scenes.
Lighting, texture, and motion are the most important elements of photorealism.
These elements distinguish Photorealism from other styles because it focuses on replicating real life visuals as closely as possible.

In visual effects, there are two main trends of Photorealism:
CGI: This version of photorealism is completely constructed using 3D rendering techniques. It involves building everything digitally, including objects, lighting, and textures, to achieve a highly realistic image. This approach is often used in animated movies or fully virtual scenes where all elements are generated from scratch.
Problems with CGI Photorealism:
High cost: Creating realistic 3D renders, requires significant computing power, which can be expensive and time consuming.
Uncanny valley: Sometimes fully CGI scenes or characters can feel “almost real” but slightly off, which can be unpleasant to viewers.
Lack of realism: Certain elements like human facial expressions or natural environments can be hard to recreate digitally.

Avatar: The Way of Water
 
House of The Dragon: city and dragon

Dune: Dessert and sand warms

Queen’s Gambit:

Composite Photorealism: This method combines real world footage with CGI elements. Artists mix live action with CG assets to create scenes that look realistic. This approach is commonly used in films to combine visual effects into real life settings, like adding digital characters or backgrounds to real world environments.
Problems with Composite Photorealism:
Mismatch between real and CGI elements: Integrating live action with CGI can sometimes lead to inconsistent lighting, shadows, or textures, making the combination less believable.
Complexity in blending: The process of blending real and virtual elements requires precise matching of angles, lighting, and colour, which can be challenging and time-consuming.
Limited flexibility: Since some elements are real, there may be limitations in terms of camera movement or scene adjustments compared to fully CGI environments.

The Umbrella Academy- JFK assassination – 1960s Dallas.

Peaky Blinders: CGI is used to enhance the industrial setting of 1920s Birmingham.

The Crown:
Queen’s Gambit: Moscow

The Weekly Activity

What is Photorealism?
Photorealism is an art style that its goal is to create images that look as realistic as photographs. Artists aim for high accuracy by capturing small details like lights and shadows, reflections, textures and perspective to make the subject appear lifelike.

Trend of Photorealism
In recent years, photorealism has become more popular in digital media, thanks to developments in 3D modelling and computer graphics. Artists now use software to create digital environments and characters that are so realistic it’s hard to tell what’s real and what’s digitally created. This trend is most noticeable in movies and tv shows, where digital elements blend smoothly with live action footage.

Photorealism in Visual Effects
Photorealism in VFX is the creation of digital elements that are identical to real world footage. VFX artists replicate real world details such as lighting, texture, shadows, and movement to make the scenes appear realistic.

Composite Photorealism
Composite photorealism is a trend within VFX, where real-world footage is combined with CGI elements. This technique is often used to extend sets, add digital characters, or create environments that would be difficult or impossible to film in real life.
For example, in TV shows like The Queen’s Gambit, Peaky Blinders, and The Crown, compositing was used to extend streets and buildings by using green screens and other techniques to blend live action shots with CGI backgrounds or elements.

The key to achieving photorealism in compositing is by making sure the lighting, shadows, and perspective of the CGI elements match the real-world footage. However, this process can be difficult because any difference between real and digital elements, such as inconsistent lighting or textures, can make the scene less believable.

CGI Photorealism
CGI photorealism is a trend in visual effects in which complete scenes are created digitally using 3D rendering techniques. This approach is often used to create virtual environments, characters and objects that would be too expensive or impossible to film in real life.
For example, in animated films or fully digital scenes in movies and TV shows like House of the Dragon and Avatar, CGI is used to create entire worlds, characters, and action scenes that are entirely digital yet designed to look as realistic as possible.

Week 5 – The New Indexicality in Digital Media Trend: Other Indexes

What was covered in the lecture:
What is capture in VFX?
Capture in VFX is recording a real life information like movements, textures, how people look, objects and places to build digital models, animations, or simulations. This data helps VFX artists make realistic or stylised virtual scenes.

The Workshop Activity:
Types of capture used in VFX:
– Motion Capture (MoCap) – This technique records an actor’s body movements using sensors which then implemented on a digital character. MoCap creates realistic movement and is often used in movies and games to make animated characters move naturally.

– Performance Capture – An advanced type of mocap that also records facial expressions and small details. This is used for creating realistic characters like Hulk in The Avengers, Pogo in The Umbrella Academy and Avatar.

– LiDAR and 3D Scanning – LiDAR stands for light detection and ranging. This method uses lasers to map the shape of real places or objects, creating precise digital versions. It’s useful for adding realistic locations to scenes or making digital copies of real objects.

– Green/Blue Screen Markers – These are on screen reference points, used when shooting a scene. They are strategically placed on-set to save time in post-production.The size, shape, and color of the markers can vary depending on the project.

– MatchMoving – A technique that allows to add 2D, live action or CG elements into live action footage with correct position, scale, orientation, and motion relative to the photographed objects in the shot.

What’s the pros and cons of MoCap?
Advantages of Motion Capture:
1.Realism and Accuracy: MoCap captures real human movements, making animations look lifelike and natural, especially for complex scenes.
2. Efficiency and Speed: Compared to manual animation, MoCap is faster and can capture complex motions quickly, saving time in production.
3. Consistency: MoCap data allows characters to move consistently across scenes, making it easier to maintain continuity.
4. Versatility in Function: MoCap is used across different media like film, games, and VR, making it a flexible tool for different types of projects.

Disadvantages of MoCap:
1. Cost: Setting up MoCap equipment can be expensive, requiring specific cameras, suits, and software.
2. Limited Expression: Small and subtle expressions or movements might not capture well, especially without real good equipment.
3. Technical Challenges: MoCap requires a controlled setup, and errors in data capture can take a lot of time to fix.
4. Actor Limitations: The captured performance depends on the actors abilities which may limit the range of characters or motions possible.

When and for what characters motion capture will be used?
Motion capture is used when filmmakers or game designers want realistic movements for characters. It’s usually used for:
1. CGI Characters: For creatures or characters that don’t exist in real life, like Pogo in The Umbrella Academy or Hulk in The Avengers.
2. Human like Movements: To capture natural human movements for animated characters in video games, films, or VR.
3. Fantasy or Sci Fi Characters: For characters with unique body shapes or abilities, like aliens or robots, where human like movement still needs to feel believable.

The Weekly Activity:
Compare motion capture and keyframe animation. Begin with definitions of each method, then discuss the advantages and disadvantages of motion capture.

Motion Capture and Keyframe Animation are two techniques for animating characters. Each has different advantages and disadvantages that make them ideal for different types of projects in films, TV, and video games.

MoCap is a technique that uses sensors on an actor to record real life movements which allows digital characters to move realistically. Actors wear suits with sensors that track their movement, and special cameras and software process this data, making digital characters to implement the actor’s movement naturally. MoCap now offers even more advanced options like performance capture, which captures facial expressions for even more lifelike characters.
Some of the films that used MoCap are Avatar: The Way of Water and Guardians of the Galaxy, and Avengers: End Game.

MoCap has many benefits, including making movements look natural, being faster than creating animations manually, keeping movements consistent across scenes. However, it also has some disadvantages. The equipment is expensive, it might miss small facial details, and technical issues can be hard to fix.