Displays, Projectors, LED, etc

Screens, Projectors, LED, LCD, CRT, etc

Projectors

Projectors

Projection Overview

Overview

In this section, you’ll learn all about projection:

Projector Technology Classifications

History & Types: Projectors have evolved from 35mm, slide, and overhead projectors to digital models used in various settings.

Digital Projector Technologies: Key types include DLP, LCD, LED, and LCoS, each with unique features and pros/cons.

Key Projector Technologies:

Projector Hardware

In general when you see a “K” after a number when talking about projections - it is referring to the brightness-Lumens in the thousands. So 5k = 5000 Lumens. This is not referring to color temperature or resolution. That said you might get a model name like 4k32 which means 4k resolution, 32k lumens. Confusing! (If you see 4k30 or 4k60 in a spec, this may refer to 30 or 60 fps, not lumens!, extra confusing!)

Projector Size Classifications

Projector Throw

Projector throw is the ratio between distance of the projector to the target surface and the width of the projected image at that distance. The example I always give is with a 1920x1080 projector, your aspect ratio is 16:9. If we want to project an image that is 16’ wide by 9’ tall, and our lens has a throw ratio of .5:1, we need the projector to be 8’ away from the target surface: 16’ multiplied by .5 is 8’!

Throw Distance = Target PRJ Width x Throw Ratio 

See more throw formulas here. 

Projector Lenses

There are a ton of different types of lenses. Different executions require different solutions. 

Projector lenses, like camera lenses, arelenses are either interchangeable (you can change the lens on the projector body) or fixed (you can’t change the lens). Fixed can also define whether a lens has zoom capabilities or not. 

In  addition to their throw ratio, here are some lens property variables:

Projectors

Lens Types

Ultra Short Throw Lenses

Usually a throw less than .4:1 is considered an UST. 

Classic UST lenses are mirrored, shoot from the back of the projector, and have complex offsets that are calculated with exponential formulas. Mirrored lenses on projectors with interchangeable lenses are often called “hammerheads” because they look like hammerhead sharks. There also isn’t a rounded lens diaphragm; instead there is a small rectangle. I would never use a hammerhead UST in a multi-surface projection mapping scenario – the distortion and focus falloff is aggressive.

Projection-Lens-UST.png

Later, a newer UST lens was developed that shoots at a 90° angle, this is called a “snorkel” because it peaks below the projector chassis in certain configurations. It has a normal lens diaphragm. This lens is superior because it can shoot with 0 offset and the math is a lot less difficult. Also, the distortion is a lot better and can be used for mapping fairly reliably. Epson has a version of this lens that is fixed at 180°, whereas Panasonic and Barco’s version shoot at 90° and can rotate in 90° increments when you adjust the lens collar. Snorkel lenses are kind of in their own category because they sometimes have zoom, they often have a good shift range, and their throw ratio is sometimes categorized as Short Throw and Ultra Short Throw

Projection-Lens-Snorkel.png

Traditional / Normal Optics Lenses

Projection-Lens-Normal.png

Why is this projector at the top of the image field? Learn about offset here.

Projectors

Projector Manufacturers

Optoma

Great, inexpensive, projectors. Never used anything of theirs above classroom range, but I’ve always been happy with them. Particularly the GT1080 (unfortunate name) and all of its children. 

BenQ

Great slightly more expensive projectors. Ditto re: projector types.

Epson

Even more expensive. Have used all types and: very reliable, except for color matching but that’s a problem with a lot of (all?) LASER projectors. Generally speaking - Epsons have great projector black. Also, their latest 4k lineup (as of 2024) is the sharpest pixel shift I’ve ever seen. Price point is incredible. 

Panasonic

Even more expensive. All types. Ditto re: color. Latest version of 4k pixel shift is not as good as previous generations (2023). Really good projector blacks 

Christie

Even more. All types. Have used this brand the least. Though have spent an intensive 10 days with 29 of their Gryffin 50ks and they are pretty good (except their black match). They are considered to be the best by many 🤷‍♀️

Barco 

Even more. All types. Projector black matching on higher end models but must be on a flat plane with straight blends (as of 2022, hoping this changes). Hire me if you want to learn! Their color loss and color bugs are really terrible on their lasers and they are infamous for this problem. Particularly the UDM-4k22 model. That said, it excels against some competitors who have even worse gremlins. 

Projectors

How To Draw a Projector Frustum

In order to get started drawing a frustum, you need the following information:

Projection-Frustum-02.png

My throw ratio for this lens is .5:1. The lens is a center (red +) cone (without any lens shift, the projector is in the horizontal and vertical center of an image when projected on a flat surface). My ideal coverage is 16’ wide by 9’ tall. To get the distance away from the surface to the projector lens, I can multiply the target width 16’ by the throw ratio of .5. This tells me the lens distance away is 8’. If you’re just looking to get basic info, this is all you really need to do. If you need exact projector positioning or whether or not the projector fits into a specific space, then you can make a frustum in 3D.

In Vectorworks, this is quite simple. You create a rectangle that is your target size and you throw a locus in representing the projector cone. You then select both things, and select Model→Multiple Extrude and extrude by your lens distance. With the extrude dialog present on your screen, you put in your throw distance. 

Projection-Frustum-03.png

Earlier, I had said “or sample coverage.” By that I mean, if you know your frustum, but you need to determine your distance, you can use a sample dimension to model the 3D frustum, and then extend (or reduce) that model proportionally until you get to your surface (in VWX this extrude option is called “Move Face Mode”). If you’re an After Effects person, working this way is kind of like putting your anchor point at the lens and then extending (or reducing) the length proportionally to the desired distance. This keeps the aspect ratio between the cone center and the image intact! 

The other very typical lens cone you might see is one that is aligned to the top or bottom of the image. For this type of lens cone, this is what the frustum looks like. 

Projection-Frustum-01.png

Projectors

Projector Math

Disclosure & Overview

In all the eexamples below, using a 1920x1080 projector at 8’ away projecting 16’ wide x 9’ high.

Special shout out here to Sean Leo who hooked me up with some of these.

You need to use projector math for all kinds of things – but mostly for Projector Positioning and engineering.

Throw Ratio Formulas

To get Projector Width = Distance x Throw Ratio

8 x .5 = 16

To get Projector Throw Ratio = Distance / Projector Width

8 / 16 = .5:1

To get Projector Distance = Throw Ratio x Width

.5 x 8 = 16

Diagonal Dimensions

// Based on a single Projector in a blend not the blended resolution

W Width = 16 ft to inches x 12 = 192 ″

H Height = 9 ft to inches x 12 = 108 ″

pxW Pixel Width = 1920//pixel Width = 1920

pxH Pixel Height = 1080//pixel Height = 1080

inW Inches in Width = W//inches Width = 192”

inH Inches in Height = H//inches Height = 108”

//functions

pxD Diagonal Pixels = sqrt (pxW^2 + pxH^2) = 2202.90717

inD Diagonal Inches = sqrt (inW^2 + inH^2) = 220.290717

Pixels Per Inch (PPI)

There are too many ways to calculate PPi. In an array of projectors, you should use values from a single projector, as the values from an array of projectors will give you different PPi for Height than Width (even though they are the same if the projectors are spec’d the same). I don’t really understand why it happens this way.

pxD Pixel Diagonal / inD Inch Diagonal of Screen = 10

Aspect Ratio

The basic “Aspect” is easily calculated. It’s the pxW / pxH: 1920/1080 = 1.7777777778

To get the ratio, that magical little 16:9, you need to find the GCD (greatest common divisor) of pxW and pxH. You can do this by using the GCD function in a spreadsheet: GCD(1920,1080) will return a GCD of 120. To get the aspect, you divide the pxW by that GCD: 1920/120 will return 16. To get your second number, you divide the pxH by that same GCD: 1080/120 will return 9.

// Spreadsheet formula - replace pxH, pxW with the cells that contain those numbers

=SUM(pxW/GCD(pxW,pxH))&":"&SUM(pxH/GCD(pxW,pxH))

Lumens

Foot Lamberts (fL) = (Projector Brightness in Lumens / Area of Screen in SqFt) * Gain



Projectors

Projector Positioning

Positioning Overview

A projectior’s physical location in a space is specified by someone who understands throw ratio and someone who understands physical limitations of a space. That could be you! In most cases, you can get a rough projector positioning using a generic or brand specific projection calculator. If you have a more complex situation, or you’re the type of person who just likes to make sure, you can calculate this yourself fairly easily. 

Understanding Projector Lens Types and Projector Math is critical to understanding where a projector can go. You can learn to draw a frustum to figure out, or you can use formulas on their own, or (my personal recommendation), is a combination of both. 

Projector positioning is based on a projector’s frustum, which is the light cone that is emitted from a lens. You can build a frustum in 2D space and do a top view and a side view to manually calculate your projector body position. 

I did this in Adobe Illustrator for 10 years before I moved into 3D space. It makes a huge difference. I use Vectorworks, which has a projector tool, but it is limited and working from scratch is a good way to learn anyway. 

Projector Fans

All projectors have fans, which means all projectors have clearance requirements. If you put a projector in a box without airflow, you’ll break it. The clearance requirements are mixed, per side, based on the airflow required from the intake fans and outtake fans. It’s usually something weird like 8” from one side, 16” from another, nothing in front (duh), 13” from the back, and 1’ above and below. If you want to be stupid about it, you can also just see what the biggest dimension is and use that for all sides (except the front). This, too, is a good example of RTFM.

Projector Rotation

Many projectors have specifications for how they can be rotated. Some can be tilted up or down a certain amount of degrees. Some can be in both a vertical orientation in addition to a traditional landscape orientation. Some can be rotated 360° in any direction and be just fine.

Technically all projectors will work when you rotate them, but certain projectors aren’t designed to be in non-traditional angles, and doing so will result in burning the lamp out faster, breaking the fans, voiding the warranty. This is a really good example of RTFM.

Projector Lens Shift

Calculating projector lens shift if you need the projector to live somewhere outside of the “home position” is very easy. For higher end projectors, the “home position,” where the lens has 0% shift, is usually the top (or bottom) middle, or the absolute center of the projected image. The projector living at the top of the image is usually good for “grid” or ceiling positions. The projector living at the bottom is usually good for floor positions.

Projection-Lens-Shift-01.png

Overshooting & Keystoning

If you need to put your projector in a position that the lens cone doesn’t support, you can overshoot and crop your image, or overshoot and keystone your image. These two options cover your target at the expense of both your brightness (fL) and your resolution. A good example of this is installing a home projector. You might install the projector in the ceiling, but there’s no shift on the lens and the lens cone is center aligned. If your projector is far enough away, you’ll tile the projector to hit the screen, and then you can overshoot your target (project slightly bigger than is ideal), and finally, you can keystone. 

In the below example, we want to cover the entire 16’x9’ viewing area with our 1.2:1 top-aligned center cone projector, but our projector lens’ center can only live at a height of 1’ above the projection field! What do we do? 

Projection-Ted-01.png

Under these requirements, we can achieve coverage with a little fine tuning. A 1.2:1 throw ratio to cover this target means we need to be approximately 19’3” from the surface. If we instead are a few inches further away, say 19’6”, we can place the projector at 1’ above the target field and angle it down a few degrees. It will result in an image that is just slightly trapezoidal (wider at the bottom).

Projection-Ted-02.png

From here, within the projector we can “keystone” the image to correct for the slight trapezoidal visual. We can also achieve this by corner pinning if the projector offers it, corner pinning via a media server, or corner pinning in content (baking). All of these solves will turn it back into a squared rectangle, which is what we want! 

Now we’re covering the target correctly.

Projection-Ted-03.png

Basic Positioning Example

If your projector doesn’t have lens shift, then calculating the position of the projector is determined by the throw ratio against your desired coverage and the frustum type. The simplest version of this is a center cone (where the projector is aligned in the center of the image). Where a projector has a center cone, your throw ratio is .5:1, and you’re projecting 16’ wide by 9’ tall, this means that your projector needs to be 8’ from the target surface and 4’6”’ off the ground. This is a good opportunity to mount your projector to a tripod or C-stand!

Projection-Lens-HV-Center-Dual.png

Projectors

Projector Rigging & Hardware

Disclosure & Overview

I (Cam) try not to do any projector rigging because I don't want to be liable for anything hung overhead. That said, I've hung many projectors either on my own, with a team, or supervising another vendor. My recommendations here are given with a massive stipulation: proceed at your own risk.

Pro Tips

Always try to install with a buddy and multiple ladders or a lift.

Little projectors are easy to install, and the weight is often low enough that you can even hang them in a drywall ceiling using toggle bolts or strong anchors. I always buy flexible projector mounts rather than fixed position projector mounts – even in a fixed installation environment. I do this because the positioning math that comes from a manufacturer's projection calculator has a margin of error. It's a slim margin typically, but having the flexibility to tilt, pan, and roll is often critical to getting things just right.

Medium sized projectors and greater often need something stronger to safely secure above head.

When you buy rigging hardware, they supply kit for tons of scenarios. Keep the leftover hardware in a bin from your mounts. When you have missing or stripped parts, or you need an extra leg, you’ve got some backup / a treasure chest.

Get security drill bits so you can use your own screwdriver or drill gun. Make sure to turn the torque all the way down and then back up to taste so that you don’t fuck up your projectors. This is an acquired skill. Proceed at your own risk!

Read up on Mastering Projector Reigging @ vidvox.net written by ProjectileObjects for Projectors weighing less than 50 pounds.

How The Hardware Works

Projector mounts come in many shapes and sizes.

In a professional situation, you typically have five main elements:

  1. A flange or cheeseborough that connects the projector pipe to a wall, ceiling, or another pipe
  2. A projector pipe that lives between the projector mount and the flange element
  3. A projector mount – this is where you have tilt, pan, and roll capabilities
  4. An interface bracket – this is literaly connected directly to the projector (in the tripod metaphor, this is the "plate").
  5. The projector

There are versions of this where you attach the mount directly to the target surface instead of using a pipe and a flange. There are also versions of this where instead of pipe and flange, you might have threaded rod coming down from unistrut. A good projector mount gives you the ability to do any of those options.

There are also versions of this where elements 3 and 4 are combined into a projector cage.

Projector Cages

When you rent a projector for an event or temporary install, it is likely to come in a projector cage. This is recommended when you are mounting projectors to truss, and for ease of installation. Bigger projectors (typically 15k lumens or brighter), are frequently permanently installed inside of cages.

Cages are great for micro adjustments and ease of installation, but they add a lot of bulk. Good for gird, strut, and truss installations but not typically a good use of space in permanent installations that are in-wall, above ceiling, etc.

Projector Enclosures

Ocassionally, you'll work with a vendor or manufacturer to enclose the projector within a ceiling or wall or to put it outside. Ventilation is critical here. You'll either need to hook it up to building HVAC, or you'll need to build filtered intake, outtake fans and ventilation ports. I recommend working with a company that does this professionally because a wrong move here can void the warranty and kill your projector. If you're in a situation where you are forced to ignore projector manufacturer intake and outtake minimum physical clearances, you need ventilation.

Mount Manufacturers

There are many projector mounts out there. I have found that the two below are the best.

Peerless - they make great mounts for projectors <50 pounds, but they can have QA issues, so order in advance. More than once, I’ve received a mount with missing pieces. Or with all the screws pre-stripped! The mount you want is the PRG-UNV. Buy one extra for parts / return it if all the rest are good. The price is good. Some models are a little finicky with their adjustment wheels. That’s what zip ties are for! The UNV mount is good because it adds a plate that you mount to the tripod that you can slide in or out of the mount attached to a pipe, ceiling, or wall. It's sort of like a quick release plate on a tripod.

Chief (Legrand AV) - they make great mounts for projectors of all sizes and weights. This is my favorite mount company. They have a really good portrait mount that holds projectors up to 75 pounds! Preferred. RPAU is their standard mount. VPAU is their 90°. Their mounts come in black/white/silver. They also sell great pipes, flanges, and solutions for weird situations - like hanging from a drop ceiling. They have a product for that. Pro-Tip from Projectile Objects: you can find these on ebay for $50-100 less than B&H. Not sure if warrantied on resale.

To read more about rigging and projection mount best practices and tools of the trade, read on to Projector Mounting Explainer.


Projectors

Projector Troubleshooting

Mapping is very difficult!

(Even though my projector covers the whole surface needed to map)

Chances are either your projector angle is too aggressive or the lens has a sharp angle built right in due to its lens offset. Traditional Ultra Short Throw projectors (eg “hammerhead” models) have an intense offset which makes them really hard to map with. Try using lens optics that don’t have a massive offset. Traditional optics: short throw, medium throw, long throw and snorkel lenses may solve your problem. See the sections about Lens Types and offsets.

Projector Black is Aggressive

(The lights are off and your content fades to black and suddenly you see the edge of the projection, or you see plaid across a blended projection field.)

Projector Menus Look Good, But Content is Dark. WTF?

Look for a setting on the projector called something like “dynamic black.” Probably developed by the same psychopath that designed “sports mode” or “dynamic contrast” for televisions to make your content look like 1980s 25FPS BBC programming. Point being: turn this off. Impress your clients when they’re disappointed by the brightness by “fixing” this.

Projector black is bigger than content - am I not using the entire sensor?


Projectors

Projection Surfaces

You can project on almost anything to varying degrees of success. Water? Not so good. Mist? Can be good. A grey wall? Perfect. A black wall? Not so good.

The one hard-and-fast rule is that you can't really project on to a surface that is getting direct sunlight during the day – why? The sun is brighter than the projector.

Projector Paint

I've used all kinds of things. The thing that looks best is Screen Goo IMHO.

The version of Screen Goo I like best is: Screen Goo 2.0,Max contrast (.7 gain)

Have A/B’d against Paint on Screen Projector Screen Paint G005(S1 Screen Plus Silver) (1.4 gain). The difference is marginal, but enough to notice that the Goo looks better. How these compare to just a basic matte grey: also marginal.,

You can blend on the Goo and not worry about brightness changing based on the viewer’s relationship to the screen. If you walked through Penn Station between 2017 and 2020 you would have seen a 2 projector blend using a screen that’s treated with reflective properties in order to increase the projector’s gain, that when standing in the middle of the room, looked good, but when you were offset from the middle, one side of the projection would appear way brighter than the other – making the final projection look like complete shit. It's a miracle it was a live presentation for that long given that I would call it “very bad.” (FYi, a few of us worked with the company who developed this screen material, they’ve since gone out of business, and I think now are getting into edible products… rich people am I right? yikes!).

What else works is : gray paint. A gray that is 75-85% white (or 15-25% black) looks fine 95% of the time. Budget for Screen Goo, then when things get tight, hit up Benjamin Moore. Just make sure you do an eggshell finish! None of that glossy nonsense.

Projectors

Projector Mounting Explainer

Projector Mounting Overview

Safety note. For all of these options you need to have a back up plan if the mount fails. In most cases that means a safety cable attached from the body of the projector to the grid or solid architecture of the building. Anything that goes over a person’s head requires backup plans in case something fails. Also consider how far the projector could fall and if it would swing. 

 

Pipe Style Mounts

A grid is a permanent structure built in a space and attached to the architecture to support equipment rigging. It is typically schedule 40 pipe but can be a lot of different things. Galleries typically use what is called Unistrut. You can adapt with something like this and still hang from a pipe!


Pipes for projector mounting are typically Schedule 40 1.5” NPT 


Pipe-based Mounts


How to hang the projector - Best practices

In order:

  1. Attach the pipe side of the mount to the pipe.

  2. Hang the pipe and check the height (note you are calculating for where the lens is - not the mount so know the vertical size of your projector and mount)

  3. Attach a safety cable to the projector before attaching the mount. (it may block the safety cable point)

  4. Attach the projector side of the mount to the projector.

  5. Bring up the projector and slide the projector side of the mount on to the pipe side of the mount. Tighten all screws.

  6. Attach the safety cable to the grid/truss.

  7. Tighten and check everything but NOT TOO TIGHT


Projector Cages

Panasonic Projectors can fit in the EVO P10 projector cages. These are ideal for floor projection as they can be mounted vertically and they support more weight than other non-cage type vertical mounts. They also allow easier access to adjust the projector position after mounting. They require specific clamps made specifically for these frames to attach them to the grid. 

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Truss

Truss is used as a portable system for hanging equipment in temporary setups. It has an outer diameter of 2”.

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Clamps


Plywood options

If you don’t own a mount you can often use plywood and drill holes to accommodate the mounting points or make a shelf or create an adapter if you don’t have a pipe based grid to hang from.


Important things to consider:


Plywood Thickness Estimated Load per Bolt (Static Load, with Washer)

Shelf Options

Shelves are often used when projector positions are static and not likely to move in a space. These can be purchased but are rather simple to make.

Considerations:

Examples:


Projector Stands - Floor Mounted

There are many purpose built stands but even more repurposed stands. 


Speaker & tray stand style:

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Purpose built portable table style by Da-Lite

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C-Stand style mounts

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Projector Plates for Truss

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Monitors

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VESA Standards - Monitors only

VESA stands for Video Electronics Standards Association - and they set a lot of standards, primarily we talk about them in regards to monitor mounting points. In the photo above a custom VESA mount is shown that was machined to allow for ALL VESA connections.

Signal & Distribution

Signal & Distribution

Signal Types

Video Signal

// Some have embedded audio capabilities, but these signal types are primarily for video

HDBaseT is good and usually cheap. Some carry USB and network, too, so you only need to run one cable for all things. Max run is 100m. Some projectors receive HDBaseT natively, which means you don’t need an RX box. Flow example: Computer → 5’ HDMI → HDBase TX → Cat up to 100m → HDBase RX → 5’ HDMI → Projector. Network cable (cat) is cheap and can be abused.

HDMI is good for short runs <25’. Avoid longer cables with in-line boosters. They fail regularly and are super finicky.

3G SDI (1920x1080) is allegedly good up to 100m. Some projectors take this natively. I find SDI to be a pain.

12G SDI (3840x2160) is allegedly good up to 100m. Some projectors take this natively. I find SDI to be a pain.

Optical HDMI is good for runs <100m. This is a unidirectional optical cable with HDMI ends. Supports up to 4k60. Fragile. No right angles in the cable. Keep it to curves. The price is right. Can recommend.

Optical Displayport is good for runs <100m. This is a unidirectional optical cable with DP ends. Supports up to 8k(?) Fragile. No right angles in the cable. Keep it to curves. The price is right. Still need to test these bad boys, but I’m guessing they are just like their HDMI cousins, but with better EDID.

Fiber is good for super long runs >100m but it is very expensive. You need a TX (transmitter) and an RX (receiver) and the fiber cable itself. Flow example: Computer → 5’ HDMI → Fiber TX → Fiber up to 1000m → Fiber RX → 5’ HDMI → Projector. Very fragile. Keep it to curves.

VGA Lol sorry

DVI Man I wish LED drivers and rack-mountable display drawers would stop using this.

Audio Signal

Send help

Signal & Distribution

Signal Distribution Devices

Adapters

Remember when you had to buy active DVI adapters for trash can Mac Pros to get more than 3 outputs? There was one time that I was in China and needed a dozen of them and… it was hard.

If something weird is happening on a Matrix, chances are that either you’ve configured it wrong, or your adapter from the video card (DP to HDMI, USB-C to HDMI etc) is “passive.” In situations with managed EDID (say with a decimator or an RTX A Card or headless passthrough), the adapter type is irrelevant. Passive adapters also tend to not work with LED drivers (Brompton, Novastar). Most of the time, just pay the extra dough and buy an active adapter. Like this one. Xcellon works!

Here’s a mnemonic for you: If it’s iVANKY it’s Janky, if it’s Xcellon, you’re right on!

Warning that if a shop is preparing your rack for you, you need to specify this and keep your fingers crossed that they listen. Anker’s USB-C to HDMI do not work with Matrixes. I have yet to test an adapter that is still available that still works, that said, the Pengo 8RDON-C01H01T1PE will work on an Apple Device and a matrix – it’s sadly no longer for sale! Maybe our friends at SimplyNuc are building active adapters that are actually active… putting that on my to-do list.

AJA

HA5-4k

Works exactly the same as an FX4, but with less flexibility/expandability. 1x 4k60 split into 4 channels of 1080 in a 2x2 grid (essentially default mode of FX4). Highly recommended and a better price point. But no hardware sync! Who needs that anyway…

Blackmagic Design (BMD)

In general, I love BMD devices, but they can be finicky, particularly if you don’t use them often. If you plug in a BMD device and it doesn’t recognize, it’s probably because the firmware on the device needs updating. If you install the latest version of Desktop Video, and it still doesn’t recognize, you need to roll back to an older version of Desktop Video and then verify functionality and slowly update, with verification, until you get to the most recent version. To uninstall a new version that doesn’t work, first run the uninstaller, then delete the following BMD files in these two paths: /Macintosh HD/Library/Preferences/Blackmagic Design/DaVinci Resolve and /Macintosh HD/Users/me/Library/Preferences – you can read more about this technique here. Worked great for me when my Monitor 3G wasn’t recognizing.

Why my BMD Monitor and/or Recorder ins't working anymore when I plug it into my computer?

Welcome to Hell! You're going to need to find the latest functional driver by going through old versions of BMD's Desktop Video.

Why does this HDMI to SDI converter not recognize the input signal?

There are two different SDI standards: A and B.

Some projectors with native SDI use A (such as Epson’s 25k), whereas, BMD (Blackmagic Design) uses B. In order to convert SDI type you can use: a DAC70 converter. A decimator will also solve this. Jason Batcheller says you can easily switch BMD from standard B to standard A. That USB port on the device can be connected to a computer and managed via BMD software - it will allow you to change standards/update firmware.

Also, level A and B standards can cause tearing on devices that receive both types. Just test the other type and the tearing should go away!

Design Mini Monitor / UltraStudio Monitor 3G

Love this thing, but it definitely reduces frame rate over native outputs (at least on M1 OS 12.5). It also has limited rez and hz options. No WUX. Technically an EDID ghost that doesn’t consume a native output.

Datapth

FX4

The FX4 is an old standby for getting 4 channels out of a single 4k output. It also keeps those channels in-sync, so it’s an easy way to get sync out of a machine that would otherwise struggle with 4x direct 1080 outputs, but can handle a single 4k out. These devices have tons of features, including:

There is a cross-platform “Wall Designer” app to change settings via USB2. It’s clunky. At some point, I’ll do a write up.

Matrox

DoubleHead2Go or TripleHead2Go

A device that works like an FX4 but is limited to a lower display quantity. The advantage with this is that it creates a display that otherwise wouldn’t exist: 5,760x1080. This is a TripleHead configured as 3x HD outputs. Otherwise, no bells and whistles. Haven’t used these in 10 years or so, but were great back in the day and probably still useful in select situations. Works on all systems.

MST Hubs

Oddly, MST hubs achieves the same ends as an FX4, but are way cheaper as they don’t have any bells or whistles. Initial testing (circa 2019) with these devices on P4000 cards has shown that these hubs can only be used with video cards that support them, and video cards must have a native displayport, as well. This means: doesn’t work with Mac.


Signal & Distribution

All Things EDID

EDID Overview

EDID is the thing that tells a computer what kind of thing it’s plugged in to. When you open up system prefs and it says “LG Ultra HD” that’s the monitor telling the computer “what” it is. EDID emulation is helpful for when you’re doing a lot of swapping of outputs or you turn your outputs off while leaving the computer on. Managing EDID is critical for installations because when some joker accidentally unplugs a projector, you won't get a display re-arrange.

On Mac systems, you need to use Headless/Passthroughs/Decimators to emulate EDID. You can also use an FX4 to keep EDID alive while the outputs are off.

On Windows systems, you need to use the same emulationd devices, unless you’ve got your own video cards that has EDID emulation via Software. Any P-series or A-series NVIDIA card allows you to save EDID to specific outputs. Adding a headless/pass to that chain will not work. Whereas, a decimator or FX4 will work. Bonus: capture EDIDs with this software and start building a library of them so that you can emulate performance easily.

Headless & Passthroughs

Headless, also called EDID Ghosts (Fubbi), allow you to trick a computer into thinking a display is plugged in, even if it isn’t. This prevents displays from being rearranged on restart or if a projector isn’t on. A regular Headless doesn’t have a passthru. Passthrus allow you to plug something into the EDID emulation. Passthroughs are preferred if you ever want to plug something in. They are more expensive than regular headless, but worth it in almost all situations.

Edge Case: If you need to mirror a display to a headless for some utility reason, then you don’t need a headless with passthrough (a headless without passthrough is just fine). There was a bug on the GPU of the old Mac Pro trashcans (ca. 2013), that was fixed if you threw a headless on the native HDMI port In general, headeless with passthrough are more useful and the difference in cost in nominal.

Types of Passthroughts: 4k60, Wux (1920x1200), 1080p60

They come in HDMI and DisplayPort flavors. I only own HDMI versions.

Decimators

These are custom EDID emulators - they are expensive swiss army knives that allow you to trick a computer into thinking it’s receiving whatever signal at whatever HZ. Incredibly useful. Highly recommended. Expensive.


Signal & Distribution

Signal & Distro Troubleshooting

General Signal Troubleshooting

Just keep removing variables to find out where the problem is. This usually solves or is the debug process for most issues:

  1. Turn off everything.
  2. Disconnect cable from display.
  3. Reconnect cable to source.
  4. Turn on source.
  5. Wait until source is booted up.
  6. Turn on display.
  7. Wait until display is booted up.
  8. Plug in display.

If you have signal chaos in between your source and display, such as a KVM, or HDBaseT, or a Matrix, try removing that variable or swapping it for another device. Adapters, sadly, can also be the culprit. Avoid couplers, too!

If none of that works, try unplugging all peripherals from the source.

Matrixes or Passthroughs aren't Persisting or Recognizing

Headless passthroughs aren’t consistently recognized by MAC OS on M1s using USB-C to HDMI adapters. This is only true of certain adapters (passive ones).

I suspect this has something to do with active vs passive adapters. Unfortunately, none of the above tell you one way or the other in their product pages. I suspect this would be a problem on WINDOWS too, but I always use P or A cards where I’ve got EDID management, and it’s display port so it doesn’t matter.

All of these adapters support 4k60, so if you don’t have EDID requirements or persist requirements, then this doesn’t matter.

Persist Displays on Apple Silicon aren't... Persisting

On M1 Studios, if you want video to persist and you’ve the same devices plugged in to multiple ports, you shouldn’t reorder or rearrange the displays (in sys prefs). From right (close to HDMI native port) to left, it will automatically order the ports. EDII0216(1) will always be far right, and EDII0216(2) will be just to the left. If you reassign these in sys prefs, it will not persist after a restart. This is old style and I suspect an OS bug.

Missing Windows

Plugged into a monitor on a PC and can’t find your windows? If you’re connected to the internet and the computer has a VNC client installed, then just use that.

Otherwise:


Signal & Distribution

HDCP

Overview

HDCP, or High-bandwidth Digital Content Protection, is a technology that prevents the unauthorized copying of digital audio and video content. It works by encrypting the audio and video signal between the device sending the content and the device receiving it.

HDCP is required to stream content from services like Netflix, Amazon Video, and Virgin, and to play Blu-Ray discs. If a device doesn't support HDCP, or if the connection between devices isn't HDCP compliant, you might see an error message and not be able to play content. For example, if you try to connect a 4K streaming box to a TV that only supports HDCP 1.4, you might only be able to watch content in 1080p.

Here are some common HDCP error messages:

HDCP Troubleshooting

HDCP can be unpredictable with various setups, break or “stripping” HDCP is considered illegal, but there are a number of ways to do this for “legal” reasons. When the HDCP “handshake” is made, both the sending and receiving device (TV, capture card, projector, etc.) agree that HDCP content is being transmitted and act accordingly. HDMI capture cards made by Elgato, BlackMagic Design, Magewell, Matrox, etc. will not “strip” HDCP content. In order to have their products sold and licensed in the USA, they agree to meet HDCP standards. When HDCP is enabled you may see a signal that drops, is all Black, Green, or Purple. For example, older HDCP standards tend to produce some image with a wash of green color over it.

Apple computers are known to have more issues with HDCP handshakes as Apple's integrated system may trigger an HDCP “event” when certain applications are open. For example, you are plugged into a projector that does not accept HDCP (perhaps an older projector), while performing, you open a web-browser and a Netflix tab launches. This can cause your signal to drop if the device you are connected to is not HDCP compliant. On Windows machines this is a mixed bag, as there are many manufacturers and software developers, doing things differently.

Oftentimes, unbranded, or “generic” HDMI splitters, HDMI Capture Cards, and HDMI monitors, will strip the HDCP chain. It is believed that they do this by declaring / cloning an EDID that is registered as HDCP compliant, when they are not. You can find these splitters on Amazon, Ebay, AliExpress, and so on, but by cloning the EDID of another licensed device. It is usually a matter of time before the EDID is reported and blacklisted in an OS or security update. For this reason, if you plan to use an HDMI splitter to break HDCP, it is best not to spend too much, as it may only work for a year or less before being blacklisted.

Valid reasons to break HDCP:

  1. To record your own computer output / performances, content.
  2. Stabile connection to older projectors and screens.
  3. Cloning multiple screens.
  4. Connecting to devices with DVI (if you are converting HDMI to DVI)

VGA, RCA,DVI, SDI were not designed to carry HDCP (HDMI only). Most HDMI to SDI devices will “break” the HDCP chain, but if you are trying to send copy written HDCP content over HDMI to a name brand SDI converter, the signal may not be passed through, as your computer will withhold the signal to remain compliant. This can also happen with HDBaseT, NDI converters, and HDMI over RJ45 and HDMI over Ethernet converters. If stripping HDCP is important to you, when in doubt, “buy cheap!”-ProjectileObjects

Written by ProjectileObjects



Alternative Displays

A survey of various display technologies and techniques that may not fall into a typical display list

Alternative Displays

Placeholder - Survey of Alternative Displays link