The Right Projector: A Balancing Act

 Assuming you are going for the authentic projector and screen set up, rather than a TV, choosing the right projector is one of the most important decisions you will make.

 Rather than splashing out on the most expensive projector available, it is better to use a scientific approach based on the amount of light projected and the ambient light levels of the room.

 Visible light output (luminous flux) is measured in lumens but this light has to be distributed over the area of an image. This is why a large image is experienced as less bright than a smaller one even though the number of lumens from the projector is the same.

 The way in which light radiation is dispersed over distance can be seen in the following diagram with the character ‘A’ representing a portion of the different-sized images created by placing the screen at various distances (d) from the projector (s).

Most commercial projectors have an output in the 2,000 to 4,000 lumens range, so this can be used as an example when comparing various sized images.

Using the 4:3 aspect range, an image of 6′ x 8′ gives us an area of 48′ square (the image at distance ‘2d’ in the diagram). A 2,000 lumens projector would, therefore, produce around 42 lumens per square foot.

A smaller image of 3′ x 4′ (the image at distance ‘d’) gives us an area of 12′ square – a quarter smaller. Therefore, the same projector would produce approximately 167 lumens and the smaller image would appear brighter.

However, if a 4,000 lumens projector is used to create the original 6′ x 8′ image, you would only get around 83 lumens per square foot.

In this case, it would be more economical to reduce the image size than to splash out on the more powerful projector. This may or may not be practical depending on the layout of your room and the effect you are looking to create.

This example illustrates how a little bit of technical knowledge can help you to balance your home theater design with your budget. However, the puzzle is incomplete because we haven’t yet looked at the effect of ambient light on the brightness of your movie images.

Ambient Light and Contrast

 Ambient light can also be measured in lumens but, unlike your projector output, it contributes to both light and dark levels. By dividing the two values you arrive at a number representing a contrast.

 A small contrast value (e.g. 20 and below)  indicates a ‘washed out’ image of grays and whites whereas a large one (e.g. 200 and above) indicates a crisp image with clear differences between dark and light areas.

 We can extend the earlier examples by looking at the effect of using a projector in both a typical movie theater and a normal room.

Movie theaters tightly control ambient light, producing around 0.1 lumens per square foot on average. A 2,000 lumens projector producing a 6′ x 8′ image in these conditions would provide a high contrast of 42.1/0.1 = 421.

However, that same projector producing the same size image in a room of average brightness (around 45 lumens per square foot) would provide a very low contrast of 87/45 = 2

Most homeowners will be able to reduce ambient light to the 1-2 lumens range and a luxmeter can be used to measure this value accurately. With the set up detailed above, 1 lumen of background light would produce a good contrast of around 43.

Measuring and Controlling Light Levels

Luminous flux can be measured using specialized luxmeters. Although a variety of free and ‘paid for’ luxmeter apps have been developed for mobile devices, tests have so far revealed that they are unreliable and shouldn’t be used as a cheap substitute for professional hardware.

 Real luxmeters are fitted with sensors which have been adjusted to mimic the brightness sensitivity curve of the human eye and to take account of the angle of incidence of the light as it reaches the sensor.

 Once you have a value for your ambient light you can work on reducing it to the required value to provide adequate contrast for the projector/image size set up you have planned.

Start by making the room as dark as possible by ordinary means (drawing curtains, turning off all unnecessary lights, etc.).

To eliminate light from windows you have several options. Black-out curtains are ideal as they also help create a movie theater feel. If you don’t want to replace your existing curtains, consider lining them with blackout fabric. You might find that some inset blinds or drapery panels work better in your home. Rails and drapery panels can be set up across doorways too if needed.

At the same time, work on removing or reducing sources of reflected light. Mirrors and glass doors are common culprits but anything reflective (metal trims, china ornaments, poster glass, etc.) can conspire to break the movie illusion. These should be removed, repositioned and covered as necessary.

Finally, LED indicators and LCD displays on electronic devices, including your home movie kit (speaker systems, TVs, etc.), can be surprisingly intrusive. Investigate settings to see if you can turn off or minimize any of these lights. If you have the budget or craftsmanship, you might be able to find ways to cover or retract equipment during the movie itself.

One of the advantages of measuring ambient light, rather than using your judgment, is that you may find that the ambient light levels of your room are fine as they are or require minimal expense to fix.

The Final Touches

The previous sections covered the fundamentals of lighting management in home movie theater design: a bright projector and tight control of ambient lighting. Now we get to the fun part.

There are many ways to get creative and replicate that real movie theater experience. Rather than running around switching off lights, consider investing in a dimmer system to slowly bring down the lighting levels and create that pre-movie excitement. If you really want to create an impression, think about integrating lighting, curtains, screen lowering and equipment retraction into one automated system controlled by a universal remote – or phone app.

Another neat touch, especially if you are designing from scratch, is to install LED step lights into the flooring. These can be switched on during an interval to allow people to safely find their way to the bathroom or popcorn machine whilst keeping the light levels low.

Exactly when humans first started working leather is unknown because even the hardiest, most well-preserved samples will eventually decompose. However, 40,000 year old neanderthal deer-bone tools found in the Dordogne region of France are thought to have been used to soften leather and make it shiny. Researchers have compared them with tools still used in the leather trade today and, by using them in the same way, managed to create the same ridges found on the prehistoric specimens.

 If the hypothesis is accurate, this dates leather-making to the dawn of modern humans who overlapped neanderthals at this time.

 A more clear-cut example of leather-working was discovered in 2008 by an Armenian excavation team in the Areni-1 cave complex. In the cool, insulated interior of the caves, undergraduate Diana Zardaryan found a complete leather shoe made from a single piece of leather. It was later dated to around 3,500 B.C., the earliest piece of leather footwear ever discovered. A slightly later example (around 3,200 B.C.) was worn by Otzi the Iceman, Europe’s oldest mummy.

 As humans moved from a nomadic, hunting lifestyle to more settled, farming-based civilizations the use of animal skins to make leather became more widespread and examples of everything from leather clothes, shoes and saddles to leather water-skins, bags, flasks and even scrolls have been found.

 By Ancient Greek times (12^th to 9^th Century B.C.), leather-working was well-established and Homer wrote about the methods people used to dry and decrease ox-hide in his famous Iliad. Leather was so popular in Roman times (8^th Century B.C. To 5^th Century A.D.) that the Roman army were sent to battle kitted out in it.

The first tanneries were banished to the outskirts of town, where the poor people lived, and when you understand the processes used to treat the skins prior to tanning, it is no surprise.

First, the freshly-removed skin was soaked before being scoured and pounded to remove the grease. Then they were either soaked in urine (collected from citizens for the purpose) or simply left to rot so that the hairs could be removed easily. Next, the skins would be softened – or ‘bated’ – using a solution containing animal dung or, in some tanneries, animal brains! The tanner would sometimes need to work the dung-soaked skin with their feet for up to three hours at a time.

 Unsurprisingly, the tanning profession was classified as a noxious trade and subject to specific public and environmental health regulations.

After the above preparation, the skin would be stretched while treated with a tanning agent. The name comes from the early use of wood tannin from oak trees but now refers to a range of chemicals used to alter the protein structure of hide and prevent it from decomposing. In the 1840s, tanners started using trivalent chromium for the purpose while today’s tanneries make use of a range of tannin including cedar oil and alum.

Today, many of the natural substances once used in the manufacture of leather have been replaced by a cocktail of chemicals including biocides, surfactants, degreasers, swell regulating agents, lime, sulfides, caustic soda, soda ash, formic acid and many more.

Leather Upholstery in Medieval and Modern Europe

The use of leather as a fabric for chair backs and seats is thought to date from the early Middle Ages (around the 5^th Century A.D.) although there is limited evidence since chairs were less common in the home at that time and the few that there were will have mainly decomposed.  Leather upholstery did grow in popularity throughout the Middle Ages and by the dawn of the 14^th Century the art of leather detailing had become well-established on the continent. The association of leather with status and luxury steadily grew and it is said that the walls of Pope Leo X’s palace were covered with velvet overlain by stamped and gilt leather.

The Renaissance period spawned a new era of ornamental seating with studded leather-upholstered high-backed chairs from Spain and Portugal becoming popular. Various types of hide were tried from calfskin to goat although cowhide emerged as the most economical option. In the late 1700s, the Chesterfield came on to the scene, a sofa design characterized by luxurious (often leather) upholstery, deep set buttons and arms and back set at the same height.

The first tanner to set up in the US was Experience Miller who arrived in New England in 1623. By 1650, there were 51 tanners in Massachusetts and the industry took a big step forward in the early 19^th Century when Billerica native Samuel Parker devised a way to split hides to increase productivity.

The use of leather as a fabric for chair backs and seats is thought to date from the early Middle Ages (around the 5^th Century A.D.) although there is limited evidence since chairs were less common in the home at that time and the few that there were will have mainly decomposed.  Leather upholstery did grow in popularity throughout the Middle Ages and by the dawn of the 14^th Century the art of leather detailing had become well-established on the continent. The association of leather with status and luxury steadily grew and it is said that the walls of Pope Leo X’s palace were covered with velvet overlain by stamped and gilt leather.

The Renaissance period spawned a new era of ornamental seating with studded leather-upholstered high-backed chairs from Spain and Portugal becoming popular. Various types of hide were tried from calfskin to goat although cowhide emerged as the most economical option. In the late 1700s, the Chesterfield came on to the scene, a sofa design characterized by luxurious (often leather) upholstery, deep set buttons and arms and back set at the same height.

The first tanner to set up in the US was Experience Miller who arrived in New England in 1623. By 1650, there were 51 tanners in Massachusetts and the industry took a big step forward in the early 19^th Century when Billerica native Samuel Parker devised a way to split hides to increase productivity.

Leather has become one of the most popular upholstery materials in the world although some people prefer fabric. This might be because they find it softer and less prone to fading or being scratched or sometimes because they dislike the way leather can get too hot or cold. On the other hand, leather tends to be easier to keep clean (less dusting and washing), more durable and with that enduring connection to luxury.

At Octane Seating, our My Octane program blends the best of both worlds by selecting premium, colorfast leathers tanned with hand-picked raw ingredients. Our leather home theater seats are designed to feel soft yet retain the long-lasting and low-maintenance characteristic of leather. Nevertheless, the choice will be mainly a personal one.

Shooting a movie on traditional 15/70 IMAX film stock presents big challenges in terms of cost and practicality. The 15 refers to the number of perforations that run through the IMAX movie camera at one time while the 70 refers to the width, in millimeters,  of the film stock (or height in this case as the film runs horizontally through a projector). The frame size in an IMAX film reel measures approximately 70mm x 49mm which is almost ten times bigger than the 16mm x 22mm frames in movies filmed using standard 35mm film stock or the 19mm x 22mm Academy Format stock. This enables a far greater image resolution.

IMAX cameras are over 200 pounds in weight and that is before taking into account the additional weight of the film which has to be three times as long as 35mm film stock due to its larger frame size. The supports and rigging needed to move such a bulky and heavy piece of kit around a film set are considerable and the noise an IMAX camera makes is so loud that actors get irritated and all sound production has to be done post-shoot.

Section 2:  IMAX Projectors

Before the introduction of its digital projectors in 2008, IMAX rolled out its four analog projectors.

15/70 film stock runs horizontally, a departure from the traditional method which feeds the film vertically through the projector. To prevent so-called ‘gate weave’ of this large film stock, the analog IMAX projectors use four stabilization pins at the corners of the frame and a vacuum system which sucks the film against a glass element set behind the lens. The lens is bigger than the frame and can be moved by a piston if it picks up dirt (although there is also a set of dust wipers for keeping the lens clean). A 15,000W water-cooled Xenon lamp provides the light source with projection assistants requiring body armor just in case the lamp should explode due to the intense conditions it operates under.

Unsurprisingly, the analog projectors are huge pieces of kit weighing as much as a car.

In 2008, IMAX revealed their much more compact digital projection systems. These combine two digital projectors which can be used to generate the separate images needed for 3D projections or two slightly out of phase identical projections in a standard movie. Together with a mechanism which uses feedback from screen-facing cameras to make sub-pixel adjustments, this dual image technology blends the pixels of the digital image to create an unlimited resolution. The colours in an digital IMAX projector are created by an ingenious mechanism involving chips, tiny mirrors and a glass prism. The downside of this is the creation of artefacts and wear and tear caused by constant temperature extremes. Contrast is also a big problem.

The latest addition to the IMAX projector family, first installed in Toronto,  replaces the lamp and prism set up with a colored laser system. The laser system also uses dual projectors, each displaying four times the detail of its digital equivalent. There is also much better contrast allowing fine detail to be seen in dark areas of a frame even when others areas are bright.

 Section 3: Sound and Other Extras

IMAX have also pushed the boundaries of sound experience with the latest systems adding six more audio channels (four speakers overhead and an extra two side speakers). Adding a headset, that increases the maximum audio channel capacity to 14.

The way IMAX deliver the 3D experience is also unique, combining polarized glasses and an LCD shutter system. With laser technology promising even greater color and detail to come, the potential for a jaw-dropping 3D experience is there.

3D is one area of movie experience that causes a lot of controversy and the same goes for HFR (High Frame Rate). HFR movies of 48 frames-per-second can be handled with IMAX cameras and projectors and have been experimented with by filmmakers such as Peter Jackson and James Cameron.

They produce a visually more realistic image than movies running at the traditional 24 frames per-second speed. HFR also makes the 3D experience less jarring to the eyes and there are fewer artefacts such as strobing during fast camera tracking. However, some viewers admit they don’t like the effect at all, complaining that the overall feel is of a documentary rather than a movie, so it may be wise not to make a 48fps movie your very first IMAX experience.

Section 4: The IMAX Canvas – Screens Over 20m High

The immersive IMAX experience is made possible by the vast screens in place at IMAX theaters and IMAX Domes. These screens are over 20m high with the biggest of them all (32m x 23m) currently housed in Melbourne Theatre, in a seven stories deep pit. Prior to its removal during renovation, there was an even bigger screen in Sydney at 35m!

Section 1: Where Did Ergonomics Come From?

Section 2: Ergonomics in Home Theater Seating

To maximize comfort and luxury, many DIY home theaters (though not all) incorporate recliners in their seating choices, one of the most iconic ergonomically designed pieces of furniture in modern homes.

The basic recliner contains two components: a seat back which tilts backwards and a foot rest that raises upwards. Recliners are also designed to look appealing through the combination of shape and choice of upholstery. As Ergonomic Design Blog puts it: “If I want to create a comfortable chair it not only has to be comfortable but it has to look comfortable. It has to make someone want to sit in it.”

In keeping with the principles of ergonomics, it is not enough to design a recliner that allows people to lay back and put their feet up. Most people like to watch the TV when they relax and this affects the angle of their neck. As a result, designers must ensure that the reclining chair provides plenty of support to the neck and back to avoid discomfort and damage to the musco-skeletal system.

The neck is a complex structure with lots of different muscles working together to tilt and rotate the head. For example, neck flexion (the action of raising and lowering the head) involves the sternocleidomastoid muscle, scalenes, trapezius, splenius capitis, spleniuscervicis and semispinalis among others.

What’s more, researchers studying the way people look at screens have found that we tend to use our necks more than other muscles (e.g. the eyes, thorax and trunk) when tilting the head up and down. For example, in an article for the International Journal of Occupational Safety and Ergonomics (2013) it was found that for a viewing angle 40 degrees above and below the horizontal (i.e. 80 degrees total flexion), the neck moved through around 50 degrees compared with the thorax and eyes which each moved through only 13 degrees.

A good recliner can allow the movie viewer to tilt their head backwards without putting undue tension on the neck muscles, supporting the back at the same time. However, that will not compensate for poor home theater design when it comes to enjoyment.

Section 3: Ergonomics and the Home Theatre Layout

It is not enough to simply buy some ergo design seating and place it randomly within your home theater. Instead, your seating – recliner or otherwise – needs to be seen as part of an overall design project focused on the needs of those who will be sharing your movie experience.

Going back to neck flexion, it is good practise that viewers should be able to see the top and bottom of the screen without tilting their head more than 15 degrees regardless of the type of seat they are in. In practise, this means that – reclined or upright – their eye level should be set at between one sixth and one third from the bottom of the screen. The actual minimum and maximum seating distances you will need to work to will also depend on the size of the screen. This can range from under 4 feet for a 35 inch screen to around 9 feet for a 60 inch screen. Time spent experimenting with screen height, viewing distance and seating layout will be worth it in the long run.

A general tip about maximizing home theater ergonomics is to think about everything that bugs you about going out to the movies. For example, one of the most common complaints is that rows are placed to close together to pack as many people in as possible.

When designing your seating layout, as well as factoring in the horizontal and vertical viewing angles and audio speaker positioning (explained in more detail in our other posts), you need to think about the leg room people will have as they stretch out. Ideally there should be enough room to walk between rows even with all seats reclined to their fullest extent – which can add up to 30 inches to the depth of each seat! When you take this into account you might find it better to set up two rows of seats with adequate leg room rather than squeeze in an extra row.

Where multiple rows are going to be needed, consider installing a riser so that people further back are not obstructed by the people sitting in front.

By adjusting the ergonomics of your home theater, both in the seating layout and the choice of ergo design seating, your friends and family can enjoy maximum comfort and pleasure as they take in the latest blockbuster.

Visual acuity is the term used to express the clarity or sharpness of the human vision. The term 20/20 vision corresponds to the normal visual acuity. In other words, if you have a 20/20 vision you can see an object clearly placed 20 feet away from you. When it comes to the home theater setup, visual acuity deals with the maximum distance beyond which human eyes won’t be able to see the picture due to the limitations of the eyesight.

This range is difficult to exceed in most home theater setups due to space constraint. However, if you were to exceed the visual acuity limit, the picture quality from an HDTV will appear similar to a traditional TV of the same screen size.

The optimal viewing distance and screen size will depend on the resolution of the video. It is the total number of pixels displayed on the screen. So a 720 x 480 resolution means 720 x 480 = 345,600 pixels, while an HD TV with a resolution of 1920 x 1080 will have 1920 x 1080 = 2,073,600 pixels. If you have a full HD TV with a 1080p (1920 x 1080) resolution, the safest viewing distance is 5 feet or closer. However, for a 4K (3840 x 2160) resolution display screen of the same size, the distance will come down to only 3 feet. In other words, the higher the resolution, the shorter is the viewing distance.

So, if you have a slightly bigger audience size and relatively small home theater room, you may have to buy a TV or projector with higher resolution. On the other hand, if you are comfortable seating at a longer distance, you are better off buying a TV with relatively lower resolution. The bottom line is the ideal resolution and therefore the screen size depends on the width as well as the length of your home theater room. Check out this simple TV size to distance calculator based on the resolution and aspect ratio.

The horizontal viewing angle also called the field of view is the angle subtended by from each corner of the display screen to the center of the seating position. If you are going to watch the TV alone (which is highly unlikely for a home theater setup) the horizontal angle wouldn’t matter that much. However, if you are going to have multiple row seating, a wider field of view can impact your viewing experience considerably.

Usually, the viewing angle, popularly known as the “sweet spot” is 40 degrees. You can use the following formula to calculate the viewing distance having a horizontal viewing angle of 40 degrees.

Distance X 0.84 = Screen Size

So, if your screen size is 60 inches, the distance should be 71.43 inches or around 6 feet. Alternatively, if you can arrange the seats at a distance of around 8 feet (i.e. 96 inches), the maximum recommended screen is around 80 inches.

The vertical viewing angle refers to the optimal height required to mount the TV. However, there is no universal standard for mounting your TV or home theater screen as they come in different sizes and shapes. However, you need to have the middle of the TV screen at eye level for an optimal and comfortable viewing experience. The optimal height is calculated from the center because most of the action takes place in the center third of the TV or screen.

Usually, most viewers experience physical discomfort when vertical viewing angle exceeds 35 degrees. That’s why you shouldn’t mount the TV or the screen higher on a wall. If the layout requires you to do so, make sure to a tilting TV bracket to adjust the TV to an optimal viewing angle. The best way to find out the optimal TV height is trial and error. Start at the lowest possible height and raise it until you can watch it comfortably from your favorite spot.

One more important factor you need to consider is the number of audiences. If you are going to have multiple row seating, you need to look for a comfort range rather an exact viewing angle.

Calculating the exact distance between the screen and the seating is usually tricky because of the less ideal layout of the home theater room. So, instead of calculating the exact distance, it is necessary to measure the maximum and minimum distances. Determining the range of viewing distance will also allow you to arrange multiple rows of seats. Use the following simple formula to calculate the maximum and minimum distance.

Width of your TV or Screen (Not the diagonal length) X 2 = minimum distance

Width of your TV or Screen (Not the diagonal length) X 5 = maximum distance

So, if the width of your TV is 55 inches, the minimum viewing distance should be 110 inches or around 9 feet, while the maximum distance should be 275 inches or no more than 23 feet. In short, the first row of recliners should be placed at least 9 feet away from the screen. The last row should be no further than 23 feet from the screen. However, this formula will provide you with a rough idea of the distances. You can try this calculator for exact calculations.

A home theater system allows you to enjoy your favorite movies without leaving the comfort of your home. However, you need to think seriously about viewing distance before buying any of the expensive home theater equipment. You also need to consider several factors including seating arrangement, screen size, image resolution, and visual acuity while setting up your media room. This post will ensure that everyone enjoys a remarkable picture quality in your home theater.

Key Points

Videography

• How to Create a Movie From Start to Finish With iMovie
• IMovie Tutorial
• How Do I Create a Movie in Windows Movie Maker?
• Create an iMovie Project
• How to Capture and Edit Video in Windows Movie Maker
• Video Pad Tutorials
• Final Cut Pro: How to Start a Project
• Introducing iMovie

Editing

• How to Add Titles in iMovie
• Final Cut Pro: Basic Editing
• What Is Video Editing?
• Video Editing with Adobe Premiere Pro for Beginners
• GarageBand: Basic Editing

Mobile/Online Video

• Producing High-Quality e-Learning Videos
• How to Make High-Quality Videos for YouTube
• A Guide for Designing and Developing e-Learning Courses
• Video-Making Guide

Audio

• How to Find the Right Music for Your Video Project
• How to Add and Edit Audio in Movie Maker
• Editing Audio
• How to Record Audio With Wavosaur

Writing

• Easiest Ways to Add Captions to Video
• How to Add Text to Video With iMovie in Mac OS X
• Adding Titles and Credits in Windows Live Movie Maker
• Grabbing Attention With Text: Writing for Video With Ann Handley

Copyright

• Copyright Basics
• What Is Fair Use?
• Code of Best Practices in Fair Use for Online Video