To watch this video, click on the Ti125:
The choices in the infrared camera market extend beyond just camera features like resolution, Bluetooth capability and storage card size. These days the market of infrared camera accessories is a separate category in its own right. Additional lenses are among the most popular choices for addition to your basic thermal imaging camera platform, but does everyone need additional lens choices?
Infrared cameras come with a standard lens that is designed to provide a field of view that allows inspection of surfaces at a moderate distance. Obviously, when you close your distance to a target your perspective changes, often to the point that you’re unable to view the entire surface without changing positions or scanning back and forth. Sometimes we are able to adjust our position relative to our area of interest to make up for the limitations of our standard optics. It’s when we can’t adjust our position that these additional lens options are worth their weight in gold.
If I’m tasked with inspecting something like overhead bus duct, or pole mounted electrical apparatus, my field of view may require me to get closer to my target to even see the component I’m viewing. Another option is a telephoto lens. A telephoto lens optically narrows your field of view, the effect of which is to bring the object you’re viewing “closer” to the camera, or magnifying the image. If a significant portion of your inspection targets are at a great distance from where you’re able to stand and view them, then a telephoto lens is likely worth having.
On the other side of the coin are instances when our target or area of interest is too close to our position during the inspection and we can’t view the full scene as desired. This can happen in electrical rooms, mechanical areas, and in building inspections. These are excellent opportunities to employ a wide angle lens. The wide angle lens does the opposite of a telephoto; it optically widens your field of view, effectively pushing your target “away” from you, or reducing the image.
In short, what makes optional lenses right for you is the applicability to your type of inspection. If you can easily move closer or farther away, the need for an extra lens is not great. But if you need to magnify or reduce the size of the target you are viewing, optional lenses will help you get the best thermogram possible.
Think Thermally, www.thesnellgroup.com The Snell Group, a Fluke Thermal Imaging Blog content partner
One of the most widely used features added to cameras in recent years is the “auto” button or “auto range” setting. In “auto mode,” or with the touch of the “auto button,” your imager will automatically adjust the level and span setting to account for the warmest and coolest items in the field of view at that time. Some cameras have a button that is a one-time adjustment, and others have a setting that continuously re-adjusts as the camera pans around and items in the field of view change.
It is a very useful feature for sure, particularly when your inspection location changes from one ambient extreme to another. Remember, the auto feature adjusts the level and span settings to account for the warmest and coolest objects (and everything in between) in the field of view of the camera at that time. If there are extreme temperature variances in the field of view when auto is selected, and at the same time somewhere between those extremes is a thermal anomaly, the auto feature may very well mask it. See Figures One and Two below.
These two images are actually the same. In Figure One, the “auto” range was selected. As you can see, the contrast in Figure One is much wider due to the temperature of the thermal foreground of the field of view, which is the very cold morning sky. The warmest surface in each image is clearly the two noted anomalies. Had the thermographer relied solely on the auto feature when taking the above image, the switch anomalies may very well have been missed.
The auto range function must be used with care. In the back of your mind, need to have the thought that the image you see may not be at the optimum level and span settings to detect every possible problem. Manual optimization is still often quite necessary in order to detect lower grade anomalies.
Awareness of the limitations of this feature is the key to success in its use. Use it with care, and it can be your best friend. Use it frivolously and it could turn into your worst enemy.Think Thermally, www.thesnellgroup.com The Snell Group, a Fluke Thermal Imaging Blog content partner
Roof moisture inspections are one of those applications of infrared thermography that many in the industry have heard of, but not so many have attempted. It’s kind of a niche application, really. In my decade or so of experience in this industry, I’ve only had the opportunity to be involved in a handful of these types of inspections. Each one was unique, and each presented its own set of challenges.
The ASTM C1153, Standard Practice for Location of Wet Insulation in Roofing Systems Using Infrared Imaging is the guiding document for these types of inspections. It lists the conditions that have to be met in order for an attempt at a roof moisture inspection to be successful. Roof moisture inspections are really as much an art as they are a science. The standards suggest beginning your inspection an hour or two after sunset, after a sunny day. How long precisely it takes for a pattern to emerge is dependent upon many factors. Roof construction, weather conditions, camera resolution, lots of things. There’s no hard, fast rule. If there’s ballast on the roof, that impacts both what you see as well as how soon you see it. Also, the patterns often can be obscure, so it takes an experienced eye to pick out some of the lower magnitude anomalies.
What does the newly minted thermographer do then? It’s a good idea to spend some time perfecting the inspection process. If you can, try to tag along with a more experienced thermographer on your first few roof inspections. That’s a good idea with any of the applications really. Try to keep in mind that mastering an art takes time and give yourself plenty of opportunity to practice.
Think Thermally, www.thesnellgroup.com The Snell Group, a Fluke Thermal Imaging Blog content partner
Recently, I had a Level I student ask me a question I’d never heard before. He asked why there were so many palette choices on his infrared camera. Often I’m asked which palette works best, or which my personal preference is. I’d never had anyone ask me why there are so many choices. He went on to say that he had trouble picking which one to use. That’s actually kind of a nice problem to have!
By and large, which palette you apply to your images, either while inspecting or when generating a report, is a matter of personal choice. Your inspection program might dictate such things, but often they don’t, so the thermographer is given free rein to pick as they like. As sweet a deal as this is, there are some points to consider when exercising this freedom.
Whichever you choose, make sure you explain to your customer which colors denote which ranges of temperature to reduce confusion. Freedom of choice is a wonderful thing in the thermal world, just makes sure you use it wisely.
Did you know that Fluke infrared cameras can now wirelessly connect to 5 other Fluke test and measurement tools and take multiple measurements simultaneously?
The Fluke Thermal Imaging CNX™ Wireless System includes the following infrared cameras: Ti100, Ti105, Ti110, Ti125, TiR105, TiR110 and TiR125.
Allow us to send you a free Fluke Thermal Imaging CNX™ Wireless System poster and you’ll see how easy it is to:
• Connect multiple instruments wirelessly
Let’s face the facts: we are seen as experts. Customers expect answers from us, usually immediate answers. How tempting it can be to make them happy! Armed with our expensive, high-tech tools, it is all too easy to forget we can’t always come up with those answers.
The three most important words in our vocabularies should always be “I don’t know.” If that brings to mind “failure,” it should not! Once we get over the stigma of saying it out loud, the phrase can actually become a valuable tool to work with a customer. Some customers will, of course, be disappointed to not have an immediate answer; honestly, these are often the kinds of customers you don’t want to have anyway! Most will appreciate your honest professionalism and caution.
Of course saying “I don’t know…” also opens up room to also say “…but I’ll do my best to find out!” That kind of attitude not only buys some time for further study but also usually endears the relationship with the customer.
Further testing—under different conditions or with additional equipment—may be necessary to discover answers. That may mean you need to renegotiate your agreement or contract. You may need to do further research. One word of warning: if you promise to do something (“I’ll get back to you with that information…”), make sure you do. Breaking promises is a simple way to lose a customer! Some unknowns, while they may be of interest to us as a professional, may not that important in the larger scheme of things. I find customers appreciate my focusing discussions on the big picture and helping keep things in context.
In the end there may be things you don’t know and never will. Can my ego handle that? Somewhere along the way I realized that if, in fact, I never used the phrase “I don’t know,” I was probably not really an expert who was continually challenging myself. Every time I encounter limits to my own knowledge and experience, I now see them as opportunities to grow and expand and do a better job for the next customer.
I’ve been working on a project this past week with a couple of young people. I’m impressed with two things. First, they have more energy than I have. Second, I have more experience than they have. While energy is great, relying on experience often means I know how to do things “smarter,” using less energy. I know I sound like an old guy now (and I am) but it also causes me to remember how much I’ve learned from so many other people over the years. For that I am grateful!
Last week we talked about how important mastery of the basics is. If you haven’t mastered operation of your imager or the basics of heat transfer, get out a calendar and commit yourself to a plan to do so.
I also recommend keeping a list of questions you encounter. Jot them down in a notebook or on your computer. Questions like, “Why do the reflections of the ducks appear warmer than the ducks themselves?” (See below for a discussion.) Or one of my all-time favorites, “Can we see an infrared rainbow?” (Short answer: yes, but not with the technology you and I can afford!) There will be, of course, hundreds of seemingly more relevant questions to be listed and answered.
Some of the best questions are “dumb” questions, those asked in innocence or ignorance! Don’t be embarrassed by dumb questions—unless those are all you ever ask!—but embrace and learn from them. There are also many useful questions to which there are no ready answers; these cause us to stretch and seek and, I find, often lead us to new and important places.
Students in our training courses often remind us how important hands-on discovery is in the learning process. They don’t want to hear us lecture, they want to explore and discuss with others. Learning doesn’t get any better than hashing things out with each other!
I often find setting up a simple experiment with a friend can help us understand an unknown issue or answer a question. Together we can provide a valuable “check and balance” for each other and test our knowledge in several ways. At that point we can also validate it against what others have learned. If it still passes the test, only then can we cautiously accept it as a working hypothesis.
If you are going to grow in this profession, you’ll need to become an expert. Don’t duck away from what you don’t know. Dive into it and learn! And by all means explore and learn with your professional colleagues—they too will have a long list of great, dumb questions.
• Radiance from just water = emission from water + reflection from clear (cold) sky
So…if the topside of the duck is cooler than the water, then the reflection should appear warmer than both the water and the topside of the duck.
Adding the duck’s reflection to the water’s emission/reflection makes it appear slightly warmer than all else.
Nothing is so important in this business as knowing the basics. That’s why I’ve often come back to such topics as adjusting level and span or emissivity or heat transfer. You can have a great imager, good training and a picture-perfect report, but if you don’t have the basics down pat, you’ll never succeed in making a difference for your customer—and making that difference is the only way to pay the bills!
In the 30+ years I’ve been in this business I’ve seen many people try to cut corners to get going faster. In the end they always make mistakes, sometimes serious ones, and have to go back to get the basics right.
If you don’t fully understand every last feature of your imaging system, take some time over the next few days or weeks to do that. Even if you don’t routinely use a certain feature, learn how it works so you have it in your “tool kit” when you do need it.
Make sure your images are perfect– perfect focus, perfect perspective, and perfect level/span adjustments. Why would you settle for anything less?
Determine how you will incorporate radiometric temperature measurements into your work flow. There is no right way, but take the time to state it clearly so your customers understand what you are doing and why. Then follow your procedure.
Are you still feeling a bit fuzzy about some part of heat transfer and radiometric theory? Dive back into your training manual and/or take a webinar or class so you are 100% clear about it. I still find each time I go back to the basics I learn something new and reinforce what I already know.
Reports are an essential part of our work. The professional standards I mentioned last week give good guidance on what that report should look like, at a minimum. Manufacturers like Fluke have done a superb job of developing report writing software that not only makes life simple but also produces great looking reports.
The report, a great a product as it may be, is usually not our end product. It is just one of the steps along the way to having our work actually make a difference. The steps to success are not magic. They include (1) establishing good communications with the customer, (2) conducting a thorough and professional inspection with the most appropriate imaging equipment, (3) documenting our work and, finally and most importantly, (4) following up with the customer.
While our role in having work actually accomplished may be limited, I’ve often found going over the report with the customer provides a great opportunity to “close” with them and secure a promise of action on their part. On a practical level, customers often have questions, either technical questions or questions about the interpretation of our findings. Without answers, the whole process can get stalled and end up in a pile on their desk.
I remember a great thermographer at an auto plant who printed all of his reports with a highlighter-yellow border on them. When he walked around the plant, he could quickly spot his reports and immediately follow-up with his customers. His intention was not just to create a fancy report but to have that report motivate the customer to do the work to correct the problem. His simple system allowed him to get much better results than many others in his company.
I had a great example of the value of a follow-up with an insulation contractor. For whatever reason he could not make sense of the images in my report. He kept drilling in the wrong places and not finding what I said would (or would not!) be there. By the time I stopped by the job site, he was so frustrated and so sure I was wrong, he’d “blown me off.” When I showed him how to read the images—both understanding the color palette and being able to locate the problem areas—all was well and the job was completed successfully. I also made a friend and ally of him for future work.
The last contact we have with the customer should not be just sending out the report (or the invoice). We are successful only when our work makes a difference. Why? The savings in the long run, quite literally, pay our salaries! If the work is not done, we’ll end up out of a job. The best way to measure our performance is to see how often our work motivates the customer to get the job done. So pick up the phone or stop by their office and see how things are going. In the end, if you are doing your job well, they may also, as I discovered, give you more work or even a referral. Not bad for a day’s work!
John Snell—The Snell Group, a Fluke Thermal Imaging Blog content partner