Borescopes: Eye Spy

June 30, 2013
July/August 2013
A version of this article appears in the July/August 2013 issue of Home Energy Magazine.
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Remember ET’s finger? That could be seen as an advanced version of a borescope—ET could touch things and cure them. The borescopes I am describing here are cameras with illumination on flexible goosenecks that can be stuck in places that you wouldn’t be able to see otherwise, like wall cavities, or cooling coils in HVAC systems, or down pipes to look for restrictions. You might want to look into a cooling coil to check airflow blockage. You might want to look into the wall cavity to assess the condition of existing insulation or look for leaks or find a wire or pipe. The trick with a borescope is to know what you are looking at. A mass of cobwebs can look like old insulation. You can spend a lot of time puzzling out a piece of wood that turns out to be the wall. The thing is that you are looking through one tiny eye that is not connected to your head. It is often difficult to know the orientation. The focus on these units is fixed, and for some of them you have to get just the right distance away to get a handle on what you are looking at. That said, borescopes do provide a way of looking at stuff that would be impossible to see otherwise. They are tools that require familiarity both in how to operate them and in how to use them to best advantage.

Paul Raymer
is chief investigator of Heyoka Solutions, a company he cofounded in 2006. He has been wandering through the mysteries of building science since 1977. He has multiple BPI certifications and is a HERS Rater.

The other day I was trying to use one to determine if the connection behind a porch roof and the band joist of a house was open. There had been some roof damage, but we didn’t want to open up the whole roof. Unfortunately, a variety of extenuating circumstances made the probing with the borescope inconclusive. It was a cold day, making us impatient; there was a lot of bright sunshine that made the screen difficult to see; and the field of vision was quite large, so it was difficult to focus in on a particular area of concern. We just assumed that the connection was unsealed and filled the cavity with cellulose.

Extech BR250

Klein Tools ET500


Table 1. Borescopes

But other, wiser building science folks use them in other ways. Tamasin Sterner uses them to show homeowners what their attic looks like without making them crawl up through an attic hatch. Paul Eldrenkamp uses them to check out which way the joists are running.

I would suggest spending some time learning the tool before you actually use it. (I guess that’s true with most tools!) Although some more expensive borescopes have articulating heads, the camera heads on the ones I describe below are not rotatable relative to the pistol grip handle. Holding the handle and adjusting the gooseneck is a two-handed process. And you need to know which side of the image is the top. Orienting the camera is a bit like trying to solve a puzzle in a mirror with one eye closed.

All three borescope cameras in Table 1 are rated IP67. IP stands for Ingress Protection. The 6 means that it is totally protected against dust, and the 7 means that it is protected against the effects of immersion between 15 cm and 1 meter, so the camera (not the handle) can be immersed in water. All three of these systems come with a small hook to snag stuff, a small magnet to retrieve metal stuff, and a 45º mirror for looking around corners. To give myself some orientation, I attached the hook to each of the cameras oriented relative to the top of my monitor. I could see the hook in the image so I would know which way was up in my image.

Extech BR250

The Extech BR250 consists of a molded green and orange plastic pistol grip handle and a 36-inch gooseneck camera with a 9-mm (0.36-inch) head. The camera is surrounded by four LED lights. The handle weighs just about 1 lb, including four AA batteries. The monitor is detachable from the handle, allowing it to be viewed remotely. The monitor is rechargeable via a USB cable that can be attached to a computer or to a wall outlet. (The kit includes a variety of adapters for various countries.) The monitor weighs about 5.5 oz and has a 2-inch x 2-7/8-inch screen.

The only control on the handle is a rotating knob where the trigger would be that turns the camera on and off and adjusts the brightness of the lights.

The monitor has a power switch on the top and a series of connections along the left side: a USB port, a video out jack, a micro-SD card slot, and a 5 VDC jack. The camera kit comes with a 2 GB micro-SD card and a micro-SD card adapter. (Micro-SD cards are incredibly small! You will want to install this sitting at a table, not in an attic or on a porch roof.) There are four control buttons on the right side: an OK, an Up arrow, a series of lines, and a Down arrow. These control the setup and the picture taking and reviewing. This makes single-handed picture taking a clunky operation. If you are holding the camera in one hand and the monitor in the other, you have to get a finger free to press the OK button to take the picture. The kit does come with a monitor stand with a strong magnetic base and an adjustable ball socket head that could serve as an extra hand, should you have a metal surface nearby. (This is particularly useful when you are working with a furnace.) Whether the images should be still or video is set up in the Settings mode. Do this before you take the picture.

The images can be transferred to a computer either by connecting directly via the USB cable or by installing the micro-SD card in a card reader.

Results: The detachable screen is a very nice feature, and in a brightly illuminated room, the camera’s image is quite clear and would be useful for showing a customer standing below what an attic looks like (if there is lighting in the attic). In a dark space, the small lighting is dim and makes identifying objects tricky. The 9-mm camera head is small enough to pass through a small hole. Extech has extenders that will screw onto the end of the gooseneck, but the joint diameter is 19 mm (0.75 inches), increasing the size of the hole required. I was able to get an acceptably steady image with the monitor about 25 feet away from the camera. The system is solidly made. The kit is quite complete and nicely packed into its molded carrying case.

What’s included in the kit:

  • Main unit and flexible, detachable camera head
  • Detachable monitor
  • Adapter cable and various AC supply connectors
  • Mirror camera attachment
  • Hook camera attachment
  • Magnet camera attachment
  • Magnetic monitor mount
  • Video cable
  • Micro SD card and card adapter
  • Four AA batteries
  • Molded carrying case

Klein Tools ET500

The Klein Tools ET500 molded orange and black handle with its integral screen and the gooseneck camera extension weighs in at about 1.5 lb. The monitor is 1-7/8 inches x 2½ inches and is quite bright and clear. Below the screen there are seven buttons: the Power button, OK, ESC, Move left, Move right, Delete, and + Brightness, and – Brightness for the camera lights. Two more buttons are located in the standard trigger location in the pistol grip, one to take still images and one for videos. These two buttons also provide Up and Down setup functions. To the left of the screen on the side are the video out jack, a full-size SD card slot, and a USB jack. (There is also a pin-accessible RESET access opening.) The camera head is 0.67 inches (17 mm) in diameter and is surrounded by four very bright LED lights.

After you attach the camera head to the handle, pressing and holding the power switch for a few moments activates the system and turns on the screen, camera, and lights. The screen displays the LED brightness level in the upper left, the date and time in the upper right, and the amount of internal memory remaining in the lower left (max 69 MB). The image is clear and sharp in a brightly illuminated room, and the LEDs are bright enough that even in dark locations there is adequate light.

Recording a still image requires squeezing the upper (or pointer finger) trigger in the handle. A video image can be recorded by squeezing the lower (or middle-finger) trigger in the handle. Although they are handy if things are stable and you’re not extending yourself in an odd configuration, these triggers can be inadvertently pressed, producing some interesting, avant-garde images.

Results: The ET500 had the best image of these three borescopes. The diameter of the camera head does result in good images, but also means that you need to make a bigger hole. The attachable tools have a bigger head to grip and are substantial in size. For image quality, this would be my personal choice. The recorded video could be used to communicate issues to a customer.

What’s included in the kit:

  • Main unit and flexible, detachable camera head
  • Mirror camera attachment
  • Hook camera attachment
  • Magnet camera attachment
  • USB power adapter and charger
  • USB data and charger cable
  • RCA composite A/V to 3.5 mm mini A/V cable
  • Quick Start Guide
  • Software and Installation manual CD-ROM
  • Molded carrying and storage case

General Tools DCiS1 iBorescope

The iBorescope is unique in that it requires a smart phone to work with, since it does not come with a video screen. The pistol grip handle weighs just over 0.5 lb with the gooseneck camera attached. It is molded of two-tone gray plastic. The only control on the handle is a rotating knob to activate the camera and lights and the internal Wi-Fi. An LED mounted on top glows red when the system is initially activated and turns to green when the Wi-Fi link is functional. On the right side of the top are a low power LED indicator and a charging LED that glows orange until the system is fully charged, at which point it turns off. Also on the right side are a 5 VDC power in jack and video out jack. The system will work with either an Android or an Apple-based system like the iPhone or iPad. The iBorescope app is downloaded from the Internet and loaded on the phone or other device. Once loaded, starting up the camera establishes a link and the output can be viewed.

The camera is 0.39 inches (10 mm) with two bright LED lights. The camera is best at close range to the object being inspected, with a macrolike focus. Room-size images are blurry, but at close range, the lights are bright enough to wash out the image entirely. Taking the still or video image on the phone or iPad is much like taking any image on the phone or iPad. That does make this a two-handed project—one hand for the phone and one for the camera, unless the camera can be set down somewhere handy.

Results: Smart phones are taking over the world! The DCiS1 has the advantage of a separate screen, but the image is pretty fuzzy except at close range. I was able to monitor the camera’s image on my phone from 40 feet away, however, through a couple of walls, so you could use the camera to explore, as long as the camera stays close to what you are looking for.

What’s included in the kit:

  • Main unit and flexible, detachable camera head
  • Mirror camera attachment
  • Hook camera attachment
  • Magnet camera attachment
  • Video cable
  • USB charging cable
  • Molded carrying case

Know Your Borescope

Different tools are great for different purposes. So the trick is not to just go out and buy a borescope because they are cool, but to try to figure out what you will be using it for. If you want to record bright, beautiful images of attics or crawl spaces and want to be able to look under and into things where a regular camera is not going to work, look for a unit like the ET500 that has a larger camera and brighter lights. If you want to show people what their attic looks like using a detachable screen, the Extech does a great job with a small camera and reasonably bright lights. If you are going to go into cavities or down pipes to seek things at close range and want to use your smart phone, then the DCiS1 is a good choice.

Note also that there are a lot of other products in this field—really simple and really sophisticated products. Bill Spohn of TruTech Tools says that General Instruments has about 21 different models, and some of the camera heads get as small as 4 mm (0.157 inches). From my own experience and from other energy auditors, I wouldn’t put a borescope at the top of my tool list. But you have to realize that most of us have never considered that there would be a tool that could do what these tools do, so we never thought of ways to use one and we never missed having one! Now that these tools exist, we can think differently.

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