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When is it Time to Change a Channel Letter Face?
Sep 05 2017 10:25:58 , 1295

 

John Baylis

 

A channel letter’s face (acrylic) is a critical performance variable, and updating a face can need to occur for several reasons. This article reviews some of the potential situations that may prompt a sign owner to consider a face change, including acrylic fading, original color choice performance and letter illumination issues.

Fading

Front lit channel letter faces are constructed of colored acrylic. Just as with other letter components, acrylic varies in quality.

When the sign is mounted outdoors, face acrylic is exposed to several environmental challenges (such as temperature extremes, rain and ice) but one of the most important is sun exposure. Acrylic which receives extended direct sunlight has the possibility of color fade. Acrylic color fade is a serious issue that can impact a letter sign’s appearance and performance.

Some acrylics are more susceptible to color fade than others. High quality channel letters will be constructed with 3/16” colorfast acrylic. This acrylic density is designed to withstand the rigor of continuous outdoor use.

Lower density face acrylics are also specified for channel letter signs (typically 1/8”.) This product is less costly but may be more prone to color fade.

Fade can do more damage than negatively impact a sign’s appearance. It can also influence the reputation of a business. If a company is unconcerned about the appearance of their primary exterior sign, how confident can a consumer feel that they will receive good service from that company?

In summary, color fade is one potential reason for face replacement and it should be completed prior to the fade becoming obvious and unsightly.

Color Choice

Another potential face change reason is a poor initial color choice. Some acrylic colors produce a much better performance (in terms of visibility and conspicuity) than others. This particularly applies to a channel letter sign’s night (illuminated) appearance.

For example, is your client considering a face color of dark blue? You may want to ask them to reconsider as that choice may necessitate a future face change. Dark blue can have challenges when utilized in a channel letter face.

Client requests for blue acrylic are understandable. Blue has many positive qualities as a marketing and branding color. For example, trust, honesty and loyalty are often associated with blue (“true blue”.)

However, darker blue acrylic tends to absorb much of the letter illumination rather than emitting it. This can result in a sign that has far less night conspicuity than other acrylics.

In addition, the color blue tends to produce more of what is called “disability glare” than other colors. The human eye lens cannot focus sharply on blue because blue light focuses slightly in front of the retina, which may cause a distracting halo to appear around blue lighting. By comparison, both the colors red and green focus precisely on the retina.

This problem also occurs because the blue light wavelength is among the shortest in the visible light spectrum.  Because they have shorter light waves, blue light produces more visual flicker than longer, weaker light wavelengths (such as red or yellow.) Again, this flickering can create a glare (or halo) which may reduce the sign’s legibility.

So the color blue must be used carefully with channel letter signage. If your client wants to avoid the potential problems with this color but still prefers a blue presence what are some potential solutions?

One potential visibility solution is specifying white face acrylic instead, and then apply what is called a “reveal” blue vinyl configuration. This layout provides your client with their desired blue presence, but has a much higher degree of night legibility because of the white border that frames the blue on the letter face. The photos below show day and night images of a channel letter sign with a reveal configuration.

Another option is to ask your client if they would consider a lighter shade of blue acrylic. A lighter shade may improve the night visibility.

Finally, perforated blue vinyl could be specified (using blue in “perf” would require digitally printing perforated film as a custom color.) That configuration would provide a blue day appearance but a white (and highly visible) night presence. Perforated vinyl is further discussed below.

Two other colors which may have similar issues to dark blue are burgundy and dark green. If your customer specifies either of those face colors (whether for acrylic or applied vinyl), let them know that configuration could produce night visibility issues.

Color Choice and Night Visibility

Along the same lines, another potential re-facing reason is some colors simply outperform others for night visibility and legibility. For example, the color red can have an excellent night signage performance. If a company conducts a substantial amount of business after dark, a change to red faces may increase their sign performance.

One reason for red’s strong visibility is the structure of the cones in the human eye. Cones are photoreceptor cells, and they are more sensitive to colors with longer light wavelengths such as red.

Cones (which detect color) lie roughly in the center of the pupil. Our cones perceive light from about 570nm to 700nm (nanometers), and provide us with our color vision. If the light drops below the cone minimum (570nm) we lose our color vision because our cones do not absorb light at these wavelengths.

This is why you can perceive objects and shapes in the dark but not their colors. And since there is a higher proportion of red-receptive cones in the eye, red is one of the first colors to become visible in the dark.

That is why companies who conduct much of their business at night (such as liquor stores, restaurants or bars) should consider re-facing to red acrylic on their channel letter signage.

Incidentally, this is why some cars have red-illuminated instrumentation gauges. Superior night visibility.

New Vinyl Technology

Another potential re-facing reason is the development of perforated (or day/night) vinyl. This product has the capacity to change a letter set’s illuminated color appearance. This juxtaposition of color from day to night can be highly beneficial to a channel letter sign’s overall visibility and performance.

For example, a sign may receive a higher degree of daytime visibility with a dark letter face appearance (perhaps because the sign is mounted on a white building facade.) However, the night appearance would be substantially more prominent if the illuminated letters were white.

Day/Night vinyl can solve this visibility issue and result in a channel letter sign which has excellent conspicuity both day and night. This illumination technology is another viable reason for a customer to consider channel letter re-facing.

LED Issues

Illumination issues with channel letter LED can be another potential re-facing reason.

LED has two main potential issues. First, certain acrylic face colors will sometimes exhibit “hot spots” or tiger striping. Hot spots occur when one area of the letter face is conspicuously brighter than an adjacent area.

A second common LED issue is the visibility of the actual modules behind the letter face acrylic. Module visibility is unsightly and does not project a professional image for the sign or the business. Some darker yellow acrylic shades are prone to this issue.

One potential “hot spot” and module visibility solution is to replace the current acrylic with a new face that includes diffuser film placed on the interior. That will address both the visible LED module issue and the hot spotting.

Conclusion

Signage customers may wish to replace their existing channel letter faces for a number of reasons. They include acrylic fading, superior color options and new illumination technology. Visible LED modules and/or “hot spotting” are two additional issues that may require face replacement to be solved.