What Pitch Is Right For My LED Signs?

Determining the correct ‘Pitch’ of your Monochrome and Color Outdoor LED Signs can be a confusing topic. Every sales person has an opinion. Unfortunately the recommendations of a sales person can sometimes be influenced by what products are available to him and what is in stock. In other words, sometimes the recommendations of a salesman is what is best for him/her not what is best for you and your business.

I am going to give you a quick guide for determining what pitch is best for you so you will not be dependent on a salesman to determine what is best. We will need to start with what pitch is and why it is important.

What is Pitch and Why You Should Care

Simply put, the pitch is the distance from the center of one pixel to the center of an adjacent pixel. This is most commonly expressed as a measurement in Millimeters. For instance, 12mm, 34mm, 63mm, 89mm, just to name a few of the most common pitches. In a sign with a 20mm pitch, the distance from the center of one pixel to the center of the next pixel is 20mm.

Okay, that is easy enough but why should you care? There are two reasons: resolution and price.

The smaller the pitch is, the more pixels you can pack into each square foot (or meter). Here is an example. At a 20mm pitch, for a 8′ x 10′ Color LED Sign, you will have a matrix of 112 pixels high x 144 pixels wide. At a 34mm pitch you will have a matrix of 64 pixels high x 88 pixels wide.  At a 45mm pitch you will have 48 pixels high x 64 pixels wide. As you can see, when you are dealing with set size LED Sign, the smaller the pitch the more pixels you get.  That adds up to higher resolution.

You might be thinking  “Well shoot, I should just get the smallest pitch I can!” You won’t end up with a grainy sign with that philosophy but you might end up spending more than you need to! That means there is more to the equation then we have covered so far. Here is the other big consideration.

The human eye does not and cannot see every detail. When you look at an LED Billboard (the big billboards you view from 800′ – 1000′ away) your eye does not see every pixel and every LED, it fills in the blank spots to makes a complete image for you.  You are generally to far away and the sign is to big for you to pick up the fine details. On the other hand if your are standing 100′ feet away from an LED Sign you will be able to pick out more details. If the pixels are not close together (tighter pitch) you will be able to make out the gaps between pixels and the image will look very pixelated. LED Billboards have a much larger pitch (frequently around 89mm) but they are to far away for you to see the gaps.

That is where the price comes into the picture. If you do not need a tight pitch to get a good image, why pay for one? Your application and sight specific factors as well as the type of LED Sign (Monochrome or Color) will determine what the optimal pitch is for your LED Sign.

How Do You Determine The Optimal Pitch?

Determining the optimal pitch is actually a mixture of art and science. Take a look at the chart below:

led-sign-pitch

This chart will give you a starting point.If you take a look at it you see that you need a character height of at least 1″ to be readable at 50″. That is the rule of thumb for determining character height based on viewing distance.

If you continue on across the chart you will see a recommended pitch. These recommendations will work for monochrome signs but when you are dealing with Color LED Signs they serve only as a starting point.  For instance, you might want your Color LED Signs to be viewed from 100′ to 300′. As you can see at the closer distance the chart recommends a 20mm pitch but at the longer distance the chart recommends a 28 mm pitch. So what do you do? That is where the art of determining pitch comes in to play. If you are unable to decide for yourself what pitch is best I would recommend you find an LED Sign expert (remember a sign salesman is not necessarily an LED Sign expert) and discuss the pros and the cons of the different pitch choices.

The last two columns on the chart deal with the speed of the traffic who will be viewing the sign. Smaller pitches generally mean smaller signs which mean less viewing time. This is important information in determining the best character height which is partially determined by the pitch.

Conclusions

There is no absolute standard I can give you for determining the best pitch for your LED Signs. The best I can offer is a starting point. When looking to invest in LED Signs, take a look at the chart above. It will give you a really solid starting point for sizing your LED Signs. If you talk to a salesperson who is recommending something that does not make sense based on the chart, make him or her explain why they are recommending what they are recommending. Don’t let them off easy, make sure YOU understand why they made their recommendation. Then you will be able to decide if they are looking out for you or for themself.

Color LED Signs For Car Dealers, A Perfect Fit

Car Dealerships are one of the industries where I recommend Full Color Outdoor LED Signs. This is because they can sell their products with pictures and videos instead of words. A video of a convertible driving down the coast will evoke an emotional response from anyone who is interested in a convertible. In fact, they will probably be mentally picturing themselves driving that convertible down the coast!

Another advantage to car dealers is they can advertise their exact inventory. Car dealers put the cars they are ‘pushing’ or trying to get off the lot out by the street. Why is this? Because they want all the people in all those cars who are driving by their lots to see those cars. They know the cars by the street will sell the quickest. The problem is there is only so much space by the street. LED Signs allow them to advertise an unlimited number of cars. When they sell one all they have to do is take its advertising frame off of the LED Sign.

Take a look at this video of a Color LED Sign at a car dealership. Do you understand the power this has for the dealer?

Back when I was a traveling salesman I would take a trailer with LED Signs mounted on it and set it up at a business in the town I was working in. That business could advertise on the LED Sign and I got a local demo location. I noticed that when I did this at car lots, the inventory would go quickly. Why? Because they were advertising their specific inventory. When someone saw a car advertised that they were interested in, they would pull in. People can’t read the sticker price in the window of a car but they sure can read it in big bright letters and numbers on an LED Sign!

If your business, like car dealers, can sell using images and video you should consider investing in Color LED Signs. The question to ask yourself is “When selling my product is a picture worth a thousand words or does it take a thousand words to sell my product?”

Why Knowing The LED Density Is Important When Purchasing LED Signs

This is a follow up to my article on comparing quotes for LED Signs. In that article I mentioned there were technical reasons why it is better to have more LEDs in each pixel. In this article I am going to explain a few of those reasons.

Reason #1

LEDs have a unique degredation pattern. They lose approximately 20% of their brightness in the first 2,000 hours of use. After that the loss of brightness slows down to the point where they will last for approximately 100,000 hours total. This is true for all LEDs, there is no way around it, so don’t be fooled by talk of ‘special’ LEDs.

That means that Outdoor Electronic LED Signs which are rated at 5,000 NITs  will drop to approximately 4,000 NITs in the first 3 months.

For those of you who do not know,  a NIT is a  measurement of brightness, in North America the sun average sunlight is rated at approximately 5,000 NITs.  So, an LED sign must be at least that bright to compete with direct sunlight. For the sake of comparison, a computer monitor will range from 250-500 NITs which is why it is hard to see your laptop screen outside during the day.

The more LEDs there are in each pixel, the higher the LED Density is, the brighter the sign will be.

It is better to have an LED Sign with a high LED Density. This will help help to maintain the brightness level of your sign.

Reason #2

One way companies who use lower LED Densities compensate for this lower brightness is to ‘overpower’ the LEDs. This means they put more electricity into each LED to make it brighter. This increases the degredation rate of the LEDs shortening their lifespan.

If an LED Sign has more LEDs in each pixel there will be no need to overpower the LEDs which will not only reduce the amount of electricity your sign uses but will help to preserve your LEDs and their brightness.

Conclusions

When you are shopping around to find LED Signs to invest in, make sure you select one with a high LED Density.  Also, make sure the sign you are looking to investing in is rated at 5,000+ NITs. This will help to protect your investment and insure you get the maximum benefit possible for the entire life of your LED Signs.

How To Do An Accurate Comparison Of The Price Of LED Signs

You have gotten a few different bids for Outdoor Monochrome LED Signs. You have compared the technical information for them all and narrowed it down to 2 bids. You have checked the references for both companies and they are more or less equal. What do you do now to decide between the two? How can you tell which is the better value?

What you need at this point is a way to compare the two LED Signs in an apples to apples way. How you do this is by comparing the cost per LED.

The true cost of LED Signs is in the LEDs. The cost of the cabinet containing the LEDs, the circuit boards, and the power supplies are negligible. What you need to compare is how much you will be paying per LED.

The math to do this is very simple so follow along with me.

Let assume you are getting a sign with a 34mm pitch and a matrix of 24×80. The pitch is the distance from the center of one pixel to the center of an adjacent pixel. If you are not familiar with the term ‘pixel’ let me explain it really quick.

A pixel is a cluster of LEDs which when lit create a discreet point on your sign. Take a look at the picture below. You can see the individual points that make up the letters. Those points are pixels.

Pixels In An LED Sign

Pixels In An LED Sign

The number of LEDs per pixel varies with the pitch size. If your 2 bids are for signs with different pitches you need to find out why they are different and why the company quoted the pitch they did. The correct pitch to use is determined primarily by the distance people will be viewing your display from.

The matrix is simply how many pixel tall by how many pixels wide your sign is on each side. For instance if you look at the above picture, you can count that the sign is 16 pixels tall.

Now, back to our example. Look at each bid and determine how many LEDs there are in each pixel. If that information is not on the bid, call the company and ask them for it.

The number of LEDs in a pixel at the 34mm size will range from 3 to 8 LEDs. Let’s assume one bid is for a sign with 4 LEDs and the other is for a sign with 8 LEDs. Our research is done, let’s do the math.

Bid #1

This bid is for a sign with 4 LEDs per pixel. At 24×80 there are 1,920 pixels PER SIDE making it a total of 3,840 pixels in the sign. At 4 LEDs per pixels there are 15,360 LEDs in the sign. If the quote is for $20,000 the cost per LED is $1.30 (Total Price divided by Total LEDs).

Bid #2

This sign will have the same number of pixels but let’s say there are 8 LEDs per pixel. That means there are a total of 30,720 LEDs in the sign. Now, let’s say the price is a bit higher at $25,000. That makes the price per LED $0.81.

Conclusion

Even at the slightly higher price, Bid #2 is a better value. There are also technical reasons why you would want the sign with the higher number of LEDs in each pixel but on a purely price basis the second bid is the better value by a whopping $0.49 per LED.

So, when looking at bids make sure you look at the true value which is in the price per LED.

LED Sign Resources

Today is going to be a quick post with some links to websites with more information on LED Signs.

If you read these you will get more information on LED Signs. Some of the information is commercial in nature but all of the information is useful in deciding whether or not to invest in LED Signs.

If you have any questions reagrding LED Signs you can always reach me via email at keith at icatchdisplays.com.

The 3 Ways LED Signs Are Manufactured – And Why You Should Care

In a nutshell here how you make LED Signs:

  1. Make a circuit board to control the LEDs
  2. Connect The LEDs to the circuit board
  3. Provide Electricity

Obviously there is more to making LED Signs. But those technical details are common to ALL LED Signs. In this article we are focusing on the the differences in manufacturing as that is the critical information someone looking to invest in LED Signs needs to know.

The 3 different manufacturing methods all stem from one issue: Protecting the sign from the elements.

Each of the three methods has its advatanges and disadvantages. If you understand these you will be able to make a much more informed purchasing decision.

Method #1

The first way to manufacture LED Signs is to solder the LEDs directly to a circuit board.  Then an Acrylic or Plastic face is placed over the sign the seal it and protect the circuit boards. Take a look at this illustration to get an idea of what this would look like:

LED Sign Using A Soldering & A Faceshield

LED Sign Using A Soldering & A Faceshield

I am not going to spend a lot of time on this method as I just posted an article titled Faceshields, An LED Sign Saver? last friday. You can click the link if you missed the post and would like more information. Let me just provide a quick recap here:

  • This is cheapest way to manufacture LED Signs
  • These savings are rarely if ever passed on to the consumer
  • The faceshield creates glare which reduces the visibility of the LED Sign during the day
  • In my opinion, the effectiveness of the faceshield in weatherproofing the sign is questionable.
  • If there is a problem with an LED an entire circuit board must be replaced which leads to a ‘quilting’ effect in the LED Sign because the newer section is brighter
  • I do NOT recommend this manufacturing method

Method #2

Method #2 is a step up from the shield method. In this method the LEDs are still soldered directly to a circuit board BUT the entire face is weatherproofed. Take a look at this illustration:

LED Sign With Soldered LEDs & Fully Sealed Face

LED Sign With Soldered LEDs & Fully Sealed Face

This method is far superior to using a faceshield. For one thing you instantly eliminate the glare created by the faceshield increasing the visibility of your LED Signs. Also, this method of weatherproofing seems to be much more effective. If you knew which brands to look for you could drive around your town during a storm and you would find very few signs made this way having any problems.

There is however still a drawback to this method.

If there is aproblem with any of the LEDs an entire circuit board must be replaced. Again, this leads to a quilting effect on your LED Sign with the newer LEDs being brighter than the older ones.

Method #3

With the third, and last, method the LEDs are placed in a sealed, removeable pixel which has pins which plug into the circuit board. The face over the circuit board is also sealed. Look at this illustration:

LD Sign With Removeable Pixels

LED Sign With Removeable Pixels

Obviously there is no faceshield with this method which eliminates the glare issue. Again, if you knew which brands to look for and you drove around your town during a storm you find no weatherproofing issues with this method.

One of the big advantages of this manufacturing method is the elimination of the ‘quilting’ problem. If one of the LEDs has a problem you simply pop out that pixel and pop in a replacement. You don’t even have to turn off the sign to do this! That means instead of an enitr circuit board sized section being brighter, only the LEDs in the newer Pixel will be brighter.

This is, in my opinion, the best method of manufacturing. LED Signs. It has all the advantages and none of the disadvantages of the other methods.

If you would like to read more about LED Sign technology check out this link.

Faceshields, An LED Sign Saver?

First let me explain what a faceshield is.

One of the ways to manufacture LED Signs is to put a piece of Acrylic or plastic in front of the the LEDs to seal the LED Sign. Take a look at this illustration:

LED Sign With Face Shield

LED Sign With Face Shield

Manufacturers who use this method of sealing their LED Signs tout it as protection against vandals. Is this true? Should you make sure you invest in LED Signs with a faceshield? Let’s think about it.

If you were a vandal would you spend your time in front of a sign that was flashing, blinking, and attracting the attention of the all the drivers going by? I think you would be more likely to spend your time in dark areas where you could cause your mischief unnoticed.

Out of all the LED Signs my company has sold we have NEVER received a report of one being vandalized. Not one.

If faceshields don’t really help to protect the LED Sign why use one? I have only come up with one answer: cheaper production. Soldering the LEDs directly to a circuit board and then sealing the whole thing with a faceshield is the least expensive way to manufacture an LED Sign.

That should result in a price break for the consumer but somehow it never seems to work out that way.

My company brokers LED Signs which means we can sell anybodies products. We will not sell LED Signs with faceshields and here is why:

LED Signs with faceshields seem to have more problems. This is just observation on my part, driving around my town and seeing which signs seem to have problems on a consistent basis. My guess is that faceshields are an inferior method of sealing LED Signs as I notice the most problems during inclement weather.

The next problem is that faceshield produce glare. As the sun shines on the face of the sign a certain amount of the light is reflected back, off the faceshield, at the observer which reduces the apparent brightness of the LEDs behind the faceshield. If there are LED Signs in your town, drive around and take a look at them. Compare the brightness of a sign with a faceshield and one without a faceshield **during the day** (pretty much all LED Signs look good at night as there is no daylight to ‘outshine’).

So, in my educated opinion, faceshields are not the way to go. Find a brand without a faceshield and you will be happier in the long run.

If you would like to read more information on LED Sign technology, I have written a ‘technology summary’ at hubpages.com/hub/LED-Signs-LED-Displays. Or just wait and I will write more in depth articles on the technology side of LED Signs here on this blog.

If you have questions you can always send them to me at keith*at*icatchdisplays.com (just replace the “*at*” with “@”).