6000 lux to lumens projector

6000 lux to lumens projector DEFAULT
What are Lumens?

Lumens come up all the time when you’re shopping around for a projector. But what are lumens? And why are they important? Officially called ANSI lumens, this measurement shows how strong a light source is. In projectors, this relates directly to the environment where the projector will be used. (Don’t worry, we provide a quick guide to how many lumens are required for what scenarios below.)

So read on to answer the question “What are lumens?” and find the best projector for your needs.

When you’re evaluating projectors for your home or business, it’s easy to become overwhelmed with the terminology associated with the devices. While we’ve already discussed projector quality elements such as device resolution, something else to consider is the lumen count of the projector you purchase.

So what are lumens? Let’s find out and how they apply to selecting the right digital projector for your needs.

What Are Lumens in Projectors?

What is a lumen?Lumens are the measurement of brightness that a projector gives out. In the industry, the formal term is “ANSI lumens.” ANSI being short for American National Standards Institute.

The Projector Expert reports the following lumen counts of common light sources:

  • Candle – 14 lumens
  • watt light bulb – lumens
  • Sunset – lumens
  • Fluorescent lighting in office – lumens
  • Lighting on a movie set – lumens
  • Sunny day – up to , lumens

There are three key light sources in the projector realm, those being LED, laser, and lamp. It’s an extensive topic that we’ve covered in this article, but a few important points to note are that lamp projectors typically run at least lumens, while laser projectors can easily provide higher than lumens – often higher with optional equipment.

That being said, LED projectors often max out at lumens, but unlike lamp projectors, they’re known for delivering higher quality image perception. This is because LED projectors have improved color saturation and luminous efficiency, which allows LED projectors to appear to have a higher perceived brightness than their ANSI lumen measurement than they may actually possess.

Learn more about LED lumens.

What Brightness Level Best Suits Your Needs?

When you’re shopping for a projector, it’s important to remember that you can’t just go out and purchase a high lumen device and get great picture quality. There’s no one size fits all approach to choosing a projector brightness for your needs.

There are a variety of factors that affect the level of brightness needed for delivering a quality picture. We’ve discussed them in this article. However, a key takeaway is the two factors that impact projector brightness requirements are:

  • Ambient light
  • Screen size

On the topic of brightness, ambient light is worth discussing because when it isn’t controlled, it can ruin the image given off by a projector. By definition, ambient light is light that is already present in a scene before any additional lighting is added.

The most common example of this is natural light coming in through the windows, or normal room lights.

Spaces with lots of lighting need a higher brightness to deliver quality images. In a darker space, you can use a lower brightness, combined with a higher contrast ratio.  The ideal lumen range for multi-purpose spaces is to lumens.

Moving onto the topic of screen size, the larger you desire, the higher brightness is suggested for the projector in order to deliver quality images.

video-in-the-classroom-projector

Home Projectors

In a home environment, you want to ensure that you choose a projector that is rated at under ANSI lumens. This is enough to project an 80” picture with minimal distortion easily. It’s worth noting, however, that with these projectors, significant effort needs to be placed on controlling ambient light levels.

If you are looking to project large images, then you need a projector with a higher lumen count. Although they are more expensive, the imagery is less affected by ambient light.

Under ANSI Lumens

It’s easy to project an 80”+ screen size. People who choose projectors in this brightness level are usually aiming for better color performance, but on the other hand, they need to tightly control and reduce ambient light while projecting.

Above ANSI Lumens

Again, it’s easy to produce an 80”+ screen, but the image quality is less sensitive to the impact of ambient light.

We’re not saying which brightness level of these two is better. It depends on different users’ needs. Both can easily project 80”+ screens and + lumens projector isn’t always more expensive.

Projectors for Business and Education

Since business and education are vast fields, there are a few lumen thresholds that apply to those industries.

Projectors for Smaller SettingsSuggested Lumen Counts for Smaller Settings

To start, for smaller settings such as a meeting room or classroom, ANSI lumens is ideal. This setting easily projects an 80”+ screen size, at a value price point. It’s best only to use projectors with these lumen levels when ambient light is minimal.

Projectors for Medium SettingsSuggested Lumen Counts for Mid-sized Spaces

If you’re in a mid-sized meeting room or classroom, then you’ll want to explore purchasing a projector that is ANSI lumens. This also delivers high-quality images of 80”+, but the higher brightness means that the user doesn’t have to worry as much about ambient light.

Projectors for Large SpacesSuggested Lumen Counts for Large Settings

The final brightness level to note is + ANSI lumens. This provides a ”+ picture size, making it ideal for large meeting rooms, exhibition halls, auditoriums, and more. The power of these projectors means they work well even with high levels of ambient light.

Making Sense of It All

Although projectors are relatively simple to use, choosing the best one to fit your needs is a bit more difficult. When it comes to striking a balance between value and performance, you need to consider how and where your projector will be used.

If you’re planning to use the device outdoors or in a room with much ambient light, then a high lumen count is essential. The same applies to situations where you’re using a projector in a large space, and/or require a larger screen size.

On the other hand, if you’re looking for a budget-conscious solution, choosing a projector with fewer lumens is practical as long as you use it in a setting where ambient light can be controlled, and space of small to medium size.

Want to learn more about projectors? Don’t miss out on our article What to Look for in a DLP Projector.

Lumen Counts for Specific Settings

Daniel

Sours: https://www.viewsonic.com/library/tech/what-are-lumens-and-how-to-use-them-to-choose-a-projector/

With consumers becoming more and more sophisticated, there’s the need for a deeper understanding of product specifications. It is true, especially with consumer electronics, including projectors. Knowing what the terms meant is crucial, given the endless variations when it comes to quality, features, and prices of these products.

In the home theater market, one aspect consumers need to understand more is the brightness. When you know the different units of light involved in ensuring your projector provides greater clarity, you can make an informed decision. On that note, let’s compare lux vs. lumens projectors and find out more about projector brightness.

The term ‘brightness’ used here is subjective and not used in optics. When discussing light, experts typically use “luminance.” But in this article, we try to make it simple and easy to understand.

Units of Measuring Light in Projectors and Home Theater

There are several terms or units to measure light when it comes to projectors. They include lumens, lux, nits, foot-lamberts, and ANSI lumens.

Let it cool

Lux vs. Lumens

Lumens and lux are both Si-based units. Lumens measure luminous flux, which is the total amount of light a light source produces per unit of time. You might confuse luminous flux with radiant flux, but they are different. Luminous flux measures electromagnetic waves only visible to the human eye, not from all sources.

It measures the total number of quanta or packets a light source produces. A lumen is a luminous flux that a light source of one candela of intensity emits over a solid angle of one steradian. It is also the unit of measurement used for the light outputs of a projector as well as other lighting equipment, i.e., lamps.

On the other hand, lux is the unit used to measure brightness in terms of surface area. When it comes to projectors, it refers to the lumen per square meter. It measures how much incident light illuminates a surface, indicating how a human eye perceives light intensity. With this, the spread of an area’s effect on luminous flux is to be considered.

Lumen and lux are closely related to each other, measuring the illuminance of a light source but in two varying contexts. It means that a lumen is the amount of light from light sources, taking human eye sensitivity to account. Lux is how bright a light appears after considering how it spreads over an area.

If you measure them from a fixed source, the lumens should have a constant number while the lux decreases as the distance increases. As you can see, these two measures of brightness are crucial when you look for a projector. It helps you invest in a projector that will output enough light for a clear image, no matter the distance.

Lumens vs. ANSI Lumens

There are numerous specifications and features you’ll want to evaluate before buying a projector. Of them, one of the often misunderstood is the lumen quality. From the explanation above, you realize that it refers to the brightness the projector produces. Lumen is crucial as it affects the image quality displayed by the projector.

In terms of lumens, one of the things that confuse people is ANSI lumens. Some projectors list this, which is much more accurate compared to lumen observation. With ANSI lumens, the luminous flux is measured through more meticulous methods with more variables involved.

Older projectors usually only include lumen measurement, but they are often inaccurate. Newer projectors such as those used in home theaters provide ANSI lumens. It is much more realistic and quantifiable. With this, the information you obtain is more reliable when you decide to invest in a particular projector.

What is the Best Way to Measure Projector Contrast Ratio?

Number of Lumens a Projector Needs

Choosing a projector in terms of brightness depends on how you will use it. On that note, you have three things to consider. These factors are the content, ambient light, and resolution. The cumulative assessment of these factors will give you an idea of the number of lumens your projector should have.

The content or material you plan on projecting affects the number of lumens you need. A business projector used for presentations needs fewer lumens. But if you will need it for your home theater system, the number of lumens varies.

  • Business /Portable – A minimum of lumens is enough for business and personal use.
  • Home Theater – A minimum of lumens for a projector to be used in projecting television shows or movies.
  • Gaming – A minimum of lumens is ideal if you plan to use the projector mostly for gaming.

If you only need a projector for work or school work, then lumens is good enough. But if it is for a home theater, then you should start at lumens no matter the other factors. It should increase after you considered other specifications like the lux, throw ratio, contrast, input capabilities, etc.

Besides the content, you should also keep in mind the resolution. With home theaters, the common resolutions are p and 4K. Gaming platforms often use p resolutions. As for most portable projectors, they usually only have x resolutions. These things matter along with the lumens as they will ensure the projector provides you a clear image.

Don’t forget about the ambient lighting. The environment where you will project has a significant impact on choosing lumens. It directly affects brightness, after all. As for the ambient light, consider the screen size as well. These two will affect how much lumens you need to make sure your projector has enough brightness for excellent viewing.

Here is a short video of the difference between lux and lumens if you’re still confused.

Conclusion

Comparing lux vs. lumens projector is not exactly right. They refer to two different things, so a comparison of them is quite useless. They do relate to each other, but only in that they both measure the brightness produced by a light source. When choosing a projector, it is the lumens that really make a difference when in terms of brightness.

References:

  1. The Different Units of Brightness for Projectors: Lumens, Lux, Foot-Lamberts, Nits, and ANSI Lumens, BenQ, Benq.com, April 3,
  2. Difference Between Lux and Lumen, Differencebetween.com, February 23,
  3. Projector Lumens: A Complete and Accurate Guide!, Jonah Matthes, Thehometheaterdiy.com
  4. Home Many Lumens Do I Need For a Projector | Perfect Guide, Michael John, Bestvela.com, June 10,

Share this post: on Twitteron Facebookon Google+

I write dozens of helpful informational articles based on topics that I have identified again and again throughout my research and work experience. I am here to help you find the right projector. View all posts by James Core →

Sours: https://projectorninja.com/lux-vs-lumens-projector/
  1. Lg k30 at&t
  2. Fnaf we are the phantoms
  3. Baja go kart for sale
  4. Google maps location sharing

Thanks to bonemap for the link to that previous thread.

A couple of additional things. I think that having merely 50% higher illuminance from the projector than the already existing lighting is almost certainly far too low. Due to the human visual system's inherent nonlinearity (see Aolis' post), the 50% brighter won't actually look 50% brighter; it'll look 20% brighter at best. If you have any degree of control over the lighting in the venue, it's best to light up the projection surface as little as possible with other lights.

Illuminance vs Luminance: Best not get those mixed up. Casually speaking: illuminance, measured in lux (Si unit) or footcandles (imperial) is a measure of incident light hitting a surface. Luminance, measured in Candales per square metre (Si) or footLambert (imperial) is a measure of light being reflected or emitted from a given surface. When setting up cinematic projection (or for calibrating monitors), luminance is key; for example 2D cinema projection is specified at 48 cd/m^2 or 14 fL. For a super-rough rule of thumb when projecting onto a white surface, if you divide your illuminance in lux by something like , you've got a likely luminance in cd/m^2. (This will change somewhat if you have either a dirty/darker surface, or on the other hand, a screen with gain > )

I've been researching this general question myself recently, and was looking for a real-life rule of thumb for estimating a projector's illuminance on a given surface based on the ANSI Lumen rating. As DBO wrote in the other thread, the expected illuminance would be the luminous flux (number of lumens) divided by the surface area. This is based on the bold assumption that the published lumen rating of the projector is accurate. I've only measured one office-grade projector so far; it's rated at ANSI Lumen but only achieves roughly without any further correction. When correcting the (greenish) native white point to something closer to D65, it predictable got worse still, measuring no more than Based on this single sample, my rule of thumb seems to be something like illuminance = ANSI rating * / surface area. I hope to measure more projectors moving forward.

I would be somewhat distrustful of "light metre" apps on phones. I must admit I haven't tried any though. If you can, see if you can borrow a genuine light metre from a photographer. If it doesn't give you an actual lux number but has EV (exposure value), you can use a chart to estimate the illuminance. 

https://www.sekonic.com/united


Sours: https://community.troikatronix.com/topic//evaluating-lux-vs-lumen-to-decide-which-projector-is-best
How to Use a Light Meter to Measure Projector Luminance, and Understanding Lumens, Gain \u0026 Ft Lambert

Illuminance in lux plays a major role in the planning of lighting installations. The brightness of LED lamps and light sources, on the other hand, is expressed in lumens. Here you can find out the correlation between the two quantities and how to convert lumens to lux correctly. An easy online calculator will help you with the conversion.

Contents

About lux and lumens

The illuminance of one or more light sources is expressed in lux. This indicates the luminous flux used to illuminate a defined area. Illuminance in lux is therefore an important planning parameter for lighting systems. This does not determine the luminous flux emitted by the light source, but the luminous flux received depending on the beam angle and distance.

The brightness of LED lamps is usually expressed in lumens. This is the luminous flux emitted by the lamp in all directions. In the case of conventional light sources, the power in watts was often used to determine brightness. However, this information is less relevant than the lumen value due to the different light output ratios of modern LED lamps.

Difference between lux and lumens

The emitted luminous flux (in lumens) of an LED lamp is a transmission quantity. The illuminance (in lux) describes the luminous flux received and is therefore a reception quantity.

Lux to lumens conversion

In order to convert lux to lumens or lumens to lux, the correlation between the two quantities must be found. Since it is the emitted light on the one hand and the received light on the other hand, other factors also play a role. These are the beam angle and the distance between the light source and the illuminated surface.

The larger the beam angle and the distance, the larger becomes the light circle below the lamp. In this case, the lumen value per square foot decreases and the illuminance or lux value decreases too. A lamp of the same brightness with a small beam angle or short distance is the opposite. The same light output falls on a smaller area, which increases the lux value.

How many lumens has a lux?

1 lumen (lm) per square metre (m²) corresponds to 1 lux (lx). 1 lumen (lm) per square foot (ft²) corresponds to lux (lx). The following calculator will help you to convert between the two values.

Lumens to Lux Calculator

The free online calculator helps you to convert between lux and lumens and vice versa. Here you can calculate the approximate illuminance or light output using the given beam angle and the distance between luminaire and illuminated plane (floor, table, work surface, wall).

The tools in this website are provided "as is" without any warranty of any kind.

Calculation examples

Convert lux to lumens

Example: An illuminance of lux should be generated on a surface 6 ft below a spotlight with a beam angle of 30°. You want to know how much lumens the spotlight must have.

In the calculator, select Lux to Lumen as Conversion and enter as the lux value, 30 as the beam angle and 6 as the distance. After a click on the Calculate button, the size of the illuminated surface and the required lumens value are displayed.

Convert lumens to lux

Example: A spotlight with a beam angle of ° and a light output of lumens is mounted at a height of ft above a table. You want to find out how much lux the table is illuminated with.

Select Lumen to Lux in the calculator and enter as the lumen value, as the beam angle and for the distance. After a click on the Calculate button you will see the size of the illuminated area and the lux value.

What to pay attention to?

When using a single light source, it should be noted that the light distribution of many LED spotlights does not always have to be uniform within the beam angle. Especially in the peripheral areas, the luminous intensity usually decreases. So the illuminance in the light circle is not homogeneous.

For the complete illumination of rooms or specific areas with a minimum illumination intensity, in most cases several LED luminaires are used. The positions of the individual lights are chosen in a way that the light cones overlap. In order to ensure homogeneous lighting with a corresponding lux value, a professional light planning should be involved.

Conclusion

Now you know the correlation between lux and lumens in connection with distance and angle. The online calculator will help you to find a reference point for your lighting design. To be really sure whether the desired illuminance is achieved with the installed luminaires, it can be checked with a lux meter at the appropriate distance from the light source.

Sours: https://lamphq.com/lux-lumens-conversion/

Projector lumens lux 6000 to

Every home theatre or meeting room environment is unique. While projectors can be used in a variety of locations, it’s important to determine the projector light level (lumens) necessary to provide a suitable image in any given situation.

The amount of light provided by any projector is an important factor in determining the visibility of the image produced, as well as its size and ultimately its price.

This article aims to describe the important concepts related to projector light output and the effects of ambient or background light from other sources in the room, so that you can better understand how bright your projector needs to be.

It’s all about image

When it comes to projectors, you need to remember that the “image” you see is what counts. (Terminology wise, for clarity – the screen is merely where the image appears and acts as the surface that reflects the light of the image back to our eyes.)

The size of a projector screen usually matches the size of the image produced by a projector, but this is not always the case. So when considering various projection configurations, your focus should be on the size of the image the projector can produce from a given throw distance.

This comes back to brightness as the larger you seek to make the image, the more diffused the light will become, making brightness an important factor as you up the image size.

What are lumens?

Many are confused about the term “lumens” but the definition is relatively simple and merely indicates the amount of light coming from the lens of a projector.

Light is measured by this unit called a “lumen”, and each projector provides a certain number of lumens, which are distributed over the image area.

Since the projector lumens meaning describes the amount of light used to produce the image, this is the term we use to refer to the image projector’s brightness.

To determine the actual lumen level, a full white image is projected and measured. This is because, with all-white images, the light is distributed evenly over a screen. While most images will, in fact, be composed of dark areas where the light is not present or be composed of other areas where there is a colour such as red or green, a projector is rated for the maximum amount of light with a full white image.

How does light projection work?

One way to think about light projection is to compare it to water coming out from a shower head. As the distance from the showerhead increases, the spray spreads out over a larger surface area.

The amount of water dispensed from the showerhead and the water pressure will always remain constant, but the area that it covers will change depending on how far or how close you are from a specific surface.

This is similar to how a projector dispenses light onto other surfaces. The resulting effect of increasing the image size of any projected image by moving the screen further away, or by changing the throw distance of the unit, will impact the amount of light that is ultimately transmitted from of the projector, as well as the brightness seen on screen.

There will always be the same amount of light produced, but this will get spread out over a larger or smaller area, depending on your chosen configuration.

Brighter vs larger images

It’s important to remember that the image brightness is determined by the overall size of the image that’s being projected.

With projectors, we can move them closer to the screen to produce smaller images that are brighter or move them further away for larger and less bright images. This trade-off between the image size and the projector brightness is one of the most important things to consider when choosing a projector.


Brightness is measured by looking only at the white light output of a projector. Your image content is not just a white screen! Consider brightness through the colour range too - a key selling feature of 3LCD projectors.

You might be able to get away with a lower lumen output if you are projecting onto a small screen, but projectors are usually employed for their delivery of larger images, which will require a greater lumen output.

Therefore, to increase the image size and keep the same brightness of the image, you must use a projector with a higher output of lumens.

Projector Brightness Calculations

Here’s an example of what the numbers look like for one particular example.

If an image of 2m x m has an area of 3 square metres and the projector has a 2,lumen output, then there are Lux (lumens per square m) because you’re looking at 2, divided by

If, however, the image on the screen is increased to 3m x m (50% wider) by projecting at a further distance, then the area is square metres (% more) and the lumens per square meter figure becomes Lux – 2, divided by

Thus by increasing the image size, we have reduced the lumens per square meter of the image brightness. (In this case, we’re left with just 44% of the image brightness shown above!)

Background light

One of the biggest issues for newcomers to the projector world is the concern about how ambient light will impact the image quality. And it’s true that in most environments there is often background light coming into the room from various sources such as windows, doors or artificial lighting.

You’ll be lucky to find a setting that is completely dark with no secondary light sources that could potentially make your image look dull or even “washed out” on screen.

Having said this, it’s also true that this difficulty can be overcome with the right projector specification and the correct understanding of the fundamentals involved. This starts with the knowledge that as ambient light falls on your projected image, it is simply the contrast that is being reduced, not the quality of projector brightness.

Your projector is performing just as it should be, but more light is also being added to the screen by other light sources in the room

It is this background or ambient light that must be considered when determining how large an image should be and how many lumens are needed.

Another example

Consider the following situation. The background light in a room contributes ambient lumens over your screen. This results in a background light level of lumens, which is 66 lumens per square metres when you divide this figure by the 3 square metres of the screen.

Now, if we go back to the specifications detailed above, where our projector provided Lux, we must take into account the lumens of additional light from other sources to calculate the total lumens projected on the screen.

As lumens divided by 3 square meters is 66 Lux, this total comes to Lux projected on the area ( + 66 = Lux). So the total now includes the additional lumens projected on each square metre of the screen.

This may initially sound like a good thing, but we haven’t factored in contrast yet. Essentially, areas that are dark in the image will be negatively impacted by the additional background lumens of 66 Lux.


Consider contrast - not just how bright your whites are!

The overall image will be brighter but the contrast will have reduced, producing the washed-out effect we mentioned before.

Remember, the difference between the bright (white) areas of your image and the dark regions are what we call the contrast. And the contrast is important for any high-quality image projection.

If you take a look at the picture below, you can see that the image projected on the screen is pretty washed out in the dark areas that look much greyer than they should. The increased ambient light is impacting the contrast, and therefore the image quality.


Lux Image

Now if you take a look at the picture below, you can see a much higher contrast image despite the overall lumens per square metre being lower at Lux, compared to the Lux image of the one above.


Lux Image

Choosing the right projector for you

The right projector for you will always depend on your particular needs and the environment where you are planning on installing it. If you are looking for detailed and intricate images for creative work then buying a high brightness projector should be your first priority. However, if you are only projecting images in smaller, darker rooms or if your content mainly features bold, large text or simple shapes, then you can probably get away with a projector with a lower lumens output.

The bottom line is that a projector’s specified lumens aren’t the only thing that will have an impact on the final image produced by your projector.

It may be the case that you can improve your image projection by finding ways to remove background lighting, or investing in a better projector screen, rather than simply buying the projector with the highest lumen count that you can afford.

We hope we’ve made things a little clearer for you in our projector brightness guide, but if you need any more clarification on any of the issues raised in this article, simply get in touch with us at  Projectorpoint and we will be happy to help explain anything to you in further detail.

One of our friendly staff will be happy to shed some light on the topic of projector brightness and recommend some suitable projector models for your purposes – whatever they may be. You can reach us on or fill in our contact form here. Or if you’re nearby, feel free to drop by at visit us in Kingston Upon Thames.

Sours: https://www.projectorpoint.co.uk/news/how-bright-should-my-projector-be
UUO P6 LED Video Projector / 1080P / 6000 LUMENS - Under $300 - Massive 300\

Lumens Guide

Below is a fast and easy reference for you to use to help determine how bright a projector you need for business, home theater, house of worship and education environments.

Already invested in a projector, but wish it was brighter? Fear not.

Our new Black Diamond SI Screens' proprietary screen material is able to reflect the light from your projector back with so much potency it actually increases the contrast ratio of your projector by more than %, enabling you to use the projector in a well-lit space.

But for those looking to purchase a projector, read on to learn how many lumens you need for your presenting environment.

Key

* Controlled Lighting: If you plan to use your projector in a room where there are no windows, such as a basement, or if you use your projector primarily at night, any of today's projectors will provide a bright image.

Low ambient light Low ambient light: Little to no light entering room.

Some ambient light Some ambient light: Some additional light in room. Slightly dimmed, window blinds leaking some light.

High ambient light Bright ambient light: Windows open during daylight hours, lights that cannot be dimmed like in an open office settings. Bright enough for audience note taking.

Business - Screen

Looking for a projector? Click here or call ()


Home Theater - Screen

House of Worship - Screen

Education - Screen

Sours: https://www.projectorpeople.com/resources/lumen-guide.asp

You will also like:

Lux / Lummen Difference and measurement??

A projector's output should actually be measured in Lumens not Lux.

Lumens would be middle/high for CRT but pretty low for LCD or DLP.

The relationship between Lux and Lumens is that the Lumens measurment is the amount of light put out, whereas Lux is the amount of that light falling on a certain area. So a Lumen projector projecting on a 10 square meter screen will be illuminated to /10 = Lux.

To put this in context, Cinema projection specifications talk about screen illumination in terms of Foot/Lamberts, (Basically the Imperial version of the Metric Lumens)The usual spec being 14fL. To convert (roughly) Lux to Foot Lamberts, simply divide by 10, so in our example above Lux would give approx 10fL - which is the bottom end of the cinema specification.

Light meters read the light in Lux because they have a known size of sensor area, which can be related to the light amount per square meter. So to measure the light output of a projector, it's set up pointing at a screen (You should use a black screen to avoid reflections). The projector should be set up to give the maximum usable white level, using an external source (Maximum possible and maximum usable white is not always the same thing - particularly on LCD). The area of the projected image is then measured to give an area in square meters. 9 measurements are then taken (top left, centre top, top right, centre left, centre, centre right etc..)and are added together and divided by 9 to give the average Lux reading. multiply this answer by the square meter measurment to get the ANSI Lumens.
This is the 'correct' measurement technique for LCD, DLP and D-ILA projectors.
CRT projectors are different in that they cannot provide a complete white screen at the same brightness as if it was a small area of white, so they measure the brightness by using a white square, occupying 10% of the screen area, and a single measurement is taken from that, and multiplied by the total screen area.

Where ANSI is not mentioned with the Lumen rating, you can never be sure how it was measured - the usual trick is to use only the brightest measured point on the screen instead of the average.

You should also be aware that for most projectors the quoted brightness is often the best acheived with a perfect lamp in perfect conditions. When I used to be involved with the Infocomm show in the US, if a projector manufacturer wanted to quote the brightness of a projector in the shootout (loads of projectors side by side, identical sources, identical screens, in near total black out!)they had to be measured by the ANSI method, only one projector manufacturer stood by their specs and had their ratings quoted.
One year, the organisers did independent measurements of all the projectors on show,a couple of times each day, and then published the results - it was interesting to see how far some measurments were from the specification sheets! (some were less than half the specified - and this was in a show where you expect to bring the best you have!!!)

I hope this is of use,

Oasis

 

Sours: https://www.avforums.com/threads/lux-lummen-difference-and-measurement/


2027 2028 2029 2030 2031