When you are in the market for a projector, you will come across the term contrast ratio. In fact, you may have already noticed that the contrast ratio has a significant impact on the price of a projection unit.
By virtue of that alone, it would be safe to assume that contrast ratio must have a bearing on picture quality.
And that brings us to important questions such as what is contrast ratio and how does it affect picture quality? The answer to these questions will finally impact your purchasing decision.
So, continue reading to know more about static and dynamic contrast ratios and their effect on picture quality and the performance of a projection unit as well as on your overall viewing experience.
What is a projector contrast ratio and why does it matter?
Simply put, the contrast ratio is a comparison of the brightness of the brightest white and the denseness of the darkest black that the projector can produce.
Now, like other forms of display, projectors can have one or both of the following problems when displaying white and black.
- The white may come with a bias, which means it will have a tinge of another color either sienna, green, or blue.
- The black may be displayed as grey.
If the white isn't as brilliant and as pure as it should be, the image will appear dull and not bright enough. A similar effect will be experienced if the black is displayed as a shade of grey or blue instead of pure black.
These issues impact the ability of the display to relay black and white and also the darker and lighter shades of all colors. So, a deep red may appear brown while a vibrant pink may not come across as striking if the display has a low contrast ratio.
Because contrast ratio is an indication of how brilliant the brightest shades and white are as compared to the darkest hues and black, the higher the ratio the more vibrant will be the display, and the clearer and sharper will be the images.
In terms of actual figures, a contrast ratio of 2000:1 indicates that the white displayed by the projector is 2000 times brighter than the black displayed in the images.
While a contrast ratio of 1000:1 is considered adequate for most projectors and screen types when you opt for a high-end projection unit like the WEMAX Nova, you get a whopping contrast ratio of 3000:1 plus HDR 10 Support, now that's called hitting the ball out of the park.
What is static contrast ratio?
When discussing the contrast ratio of your projector, you are also likely to encounter two more related terms: Static and Dynamic.
Static contrast ratio refers to the contrast ratio offered by the projection technology used in the unit. For example, an LCD projector will have a different contrast ratio as compared to a DLP projector even when all other factors are held constant.
Also known as native contrast, the static contrast ratio reflects the tested results of the performance of the LCD panel or the DLP chip when it was made. In other words, this term is a description of what the panel is capable of offering in terms of contrast performance.
What is dynamic contrast ratio?
Dynamic contrast refers to a theoretical range of contrast that the display is capable of. So, think of this as a value that is an enhancement over the static contrast capability of the chip.
In simpler words, the dynamic contrast range is the contrast ratio that a projection unit is capable of after the effect of all the bells and whistles is added to the native contrast ratio. Hence, as you can imagine for any given projector, while the static contrast ratio stays within the range of a few hundred to a few thousand: 1, the dynamic ratio skyrockets to several hundred times that.
Because dynamic contrast enhancement is owed to the software and the additional unit components, there can be a significant disparity in the dynamic contrast of products offered by different manufacturers and also those from the same manufacturer.
To add to the problem, the technique used to measure dynamic contrast ratio can change from one manufacturer to another, so there cannot possibly be parity when it comes to this performance metric.
Differences between static vs. dynamic contrast ratio
Static Contrast Ratio
Dynamic Contrast Ratio
This is the contrast ratio that the projection technology, i.e the DLP chip/LCD panel is capable of offering.
A theoretical range of the performance of the projection unit that combines the contrast ratio provided by the chip and more significantly the impact on the contrast ratio of the firmware and the lamp power modification capability.
ANSI contrast, which involves the use of a single screen with a checkered pattern (black + white) display.
Full on/off (FOFO) technique is used to measure the dynamic contrast ratio, which involves two screens, one displaying full black and the other displaying full white.
An increase in static contrast ratio leads to discernible differences in picture quality and color saturation as well as greater image depth.
Static and dynamic contrast ratios cannot be directly compared. Moreover, in average ambient light conditions and for average display light requirements, the difference in performance may not be discernible even with a significant increase in the dynamic contrast ratio.
Realism & Adaptability
Static contrast is hard to measure but a more accurate specification of what you can expect to see on the screen.
A projector with a high dynamic ratio may not always have a high static contrast ratio as well. So, despite a high dynamic contrast ratio, you may not get the desired color saturation, image sharpness, and three-dimensional picture quality.
How is contrast ratio measured?
There is no standard measurement technique when it comes to gauging the contrast ratio of a display. So, it is an area left open to exploitation as some manufacturers do take the unscrupulous path and inflate ratings or use unstated variables to create the illusion of superior performance.
Having said that the most commonly used techniques used for measuring contrast ratio include:
ANSI Contrast (for measuring static contrast ratio)
A single screen is used for measuring ANSI contrast or the static/native contrast that the panel/chip is capable of delivering. The screen displays a checkered pattern of alternating black and white squares.
To rule out discrepancies caused by the inevitable hot spots of black and white, the average of all black output squares is pitched against the average of the output of all white squares.
This is a more realistic measurement of contrast since any moving image is bound to have both black and white displayed simultaneously. Static contrast ratio always trails behind dynamic contrast ratio.
But, that's not the problem with ANSI contrast. The main issue is that the measurement is done in ideal conditions. This means that the display is measured in a completely dark room.
Undoubtedly, ANSI contrast measurement is more reliable than dynamic contrast since it has little room for fudging. But the fact is that the performance will never be the same when you use the projector in a normal environment where the display will be affected by ambient light.
Full On/Off Contrast (for measuring dynamic contrast ratio)
Two screens instead of one are used to measure dynamic contrast through this technique. One screen displays only white images while the other displays only black images.
The blackest spot of the black screen display is pitched against the whitest spot of the all-white display to measure dynamic contrast. On the plus side, this measurement technique factors in exterior lighting conditions since an equal proportion of light is reflected from the display and back.
But, in a realistic setting, you are unlikely to encounter an all-white or an all-black display let alone the whitest white and the blackest black in the same frame all the time and every time.
So, the all-white and all-white displays lead to ideal results, which are considerably higher than that of a mixed black and white display. Hence, dynamic contrast cannot really be considered a true specification of the contrast ratio of the projection unit. It is more a theoretical metric of what the unit with all its components is capable of achieving.
Display performance of static and dynamic contrast ratio
As discussed above, the dynamic contrast ratio will often be several times higher than the static contrast ratio, with figures frequently in the range of 30,000,000:1 or more.
So, you cannot compare the static contrast ratio directly to the dynamic contrast ratio. Having said that, it is important to understand that manufacturers often choose to list just the dynamic ratio because it looks better on paper.
However, in terms of actual display performance, at best, those high figures of dynamic contrast only translate to minor improvement, and at worst, they can actually be misleading.
A lot depends on the true brightness range of the images. Consider an example of two projection units.
The first has a dynamic contrast ratio of 20,000:1 and the second has a static contrast ratio of 2,000:1. Unless you are sitting in a pitch-dark room, the impact of this enormous gap in contrast ratios will have an almost indiscernible impact on image quality.
Realism and adaptability of static and dynamic contrast ratio
When it comes to dynamic contrast ratios, the figures are heavily dependent on the projector's ability to control light output.
Many projection units are capable of adjusting lamp power to meet the average requirements of the light level of a scene. So, the lamp power is turned down for a dark scene, which essentially makes the blacks come across as deeper and darker. On the other hand, the lamp power is turned up for brighter scenes, which makes the whites appear brighter and whiter.
These adjustments are made on the fly, so as the viewer you will only feel the cumulative visual impact of this ability. While this is undoubtedly a desirable attribute, it unfairly skews the contrast ratio spec.
Also, these lamp power adjustments don't make a huge difference when the projected image is not particularly bright or dark.
In other words, while a dynamic contrast enhancement produces noteworthy figures, these rarely translate to a huge and realistic difference in image quality. On the other hand, a static contrast ratio is harder to measure, but it is very easy to see.
For example, a projection unit with a high static contrast ratio will display solid blacks and darker colors, rich color saturation, and brilliant whites along with a distinctive three-dimensionality. Along the same lines, a unit with a low static contrast ratio will suffer from an anemic display in which the darks seem washed out and the whites are dull along with low color saturation and two-dimensional images.
So, when you see the display and can't help but say, "Wow what amazing picture clarity", chances are that the unit has a high static contrast ratio, which may/may not lead to a high dynamic contrast ratio as well.
Choosing the right contrast ratio for you
In terms of static contrast for a home theater projector, a ratio of 200:1 to 300:1 is what you are likely to get from a transmissive digital projector while a ratio of 500:1 or more is to be expected from a reflective digital projector.
A static contrast ratio of 700:1 would offer good image quality but a ratio of 1000:1 would be more desirable. Of course, if you can go higher than that, you will get what can only be called exceptionally good picture quality.
That said, here are a few things to consider when choosing the right contrast ratio for your requirements:
Look for projector manufacturers that publish ANSI contrast specs
Because ANSI contrast is a more accurate and realistic specification of what can be expected from the display, always rely on the modest native contrast figures over the oft-inflated dynamic contrast figures.
Check the projection technology
In terms of technology, DLP offers a higher native contrast ratio than LCD projectors. However, LCD projectors tend to be brighter than DLP-powered units. But if you can find a unit that uses a DLP chip with a laser lamp, you can get the best of both worlds.
Refer to the same manufacturer for comparisons
Because there can be differences in the display environment used by manufacturers even when measuring native/static contrast ratio, it is best to compare and contrast static and dynamic flexibility among products from the same manufacturer.
Finally, remember that the eye test is the best test when you are trying to gauge the actual effect of the contrast ratio of a projector. If the image looks bright, deep, and sharp, there is a good possibility that the superior performance is backed by a high native contrast ratio.
Frequently Asked Questions (FAQs)
What is the significance of contrast ratio in display technology?
The contrast ratio provides a measure of how clearly you will be able to see the images on the screen as well as the overall picture quality.
A higher contrast ratio equates to that much more distinctness when it comes to various shades of the same color. It also points to a conspicuous improvement in depth.
Can ambient lighting affect contrast ratio?
Ambient light does have an impact on contrast ratio, particularly on native contrast ratio. In fact, as the ambient light increases, you will need to increase projector brightness and couple this with an ambient light-rejecting screen.
Does contrast ratio affect HDR performance?
HDR is significantly reliant on contrast ratio when it comes to offering the enhanced visual performance that it's known for. Actually, a higher native contrast ratio allows you to fully harness the capabilities of HDR.
Wrapping It Up
WEMAX offers high-quality laser projectors, LED projectors, and portable projectors with impressive native and full-on/off (FOFO) contrast ratios.
In fact, the WEMAX Nova takes the contrast ratio game to the next level with a native contrast of 3,000:1. Plus, the unit combines the famed DLP technology with an ALPD laser for exceptional brightness.
So, if you want picture quality that is at par with what you have come to expect from movie theaters, this is the projector to buy. Plus. WEMAX is a one-stop shop for all your home theater projection needs.