What’s Good:

  • Bright, Clear 3.5 inch screen
  • Excellent Interface
  • Very easy to use
  • Stunning image
  • Visual Camera (Testo 870-2 only)
  • Small and compact

What’s not to like:

  • Fixed Focus
  • No removable data card

The gloves are really off with this latest release from Testo. Quite simply it’s ridiculously good. Too good in fact. The truth is, it is so good it will probably cannibalise some sales from the higher end models, which is not the best strategy for a manufacturer. It is however good for YOU the customer.

The Testo 870 thermal imager comes in 2 model variants, the 870-1 and 870-2. The Testo 870-2 is loaded with all the features mentioned here, while the 870-1 misses out on the built in visual camera and hard carry case.

For an entry level model and at entry level price, the Testo 870 doesn’t leave you wanting for more. It has no less than a 160×120 sized detector with a thermal sensitivity of 100mk (0.1°C). This puts it somewhere between the FLIR E5 and FLIR E6 models, and is most comparable to the Fluke T105. It’s not even worth comparing it to any of the Chinese models, as the German pedigree of the Testo 870 puts it way into the top group. This is the kind of camera that 3 years ago we would have considered medium level.

Incredibly, the Testo 870 thermal imager features the super resolution function (additional cost) which takes the image up to a 320×240 resolution. This is truly an awesome feature that adds a massive amount of image quality for a nominal fee.   I will let the imagery speak for itself. ..

Testo 870 Comparison 1

Testo 870 Comparison 1

Testo 870 Comparison 2

Testo 870 Comparison 2

Testo 870 Comparison 3

Testo 870 Comparison 3

Testo 870 Comparison 4

Testo 870 Comparison 4

Testo 870 Comparison 5

Testo 870 Comparison 5

Compact without Compromise

The Testo 870 thermal imager is super compact and well laid out. Many will prefer it to the larger more capable units because the size really is comfortable and user friendly. Usually “compact” means “compromise” however the screen size is stunning 3.5 inch display, and every square inch of it is used to display imagery. This in itself is impressive for an entry level unit. The screen is uncluttered and uses the traditional Testo “folder” menu system, which unfolds each function logical, progressive fashion. The first time using the unit there presented a “zero” learning curve from it’s predecessors. I like it when manufacturer’s don’t reinvent the wheel to confuse me. Besides, this interface really works.

The central button is a joystick, which easily facilitates up/down, left/right functions and pressing confirms the selection. It couldn’t be simpler. A user customised button sits to the right of the joystick. Functions such as image type (visual/thermal), image gallery, scale, emissivity and adjustment (calibration) can individually be assigned to this customised button. By default, this is set to scale, which in my opinion is the single most important function that should be available, which leads me to my next point…

Auto Scale and Manual Adjustment

Something rarely done properly in an entry level unit is the ability to move between auto scale and a fully functioning manual adjustment method easily and efficiently. To my amazement, the Testo 870 thermal imager handles this seamlessly. By assigning scale to the user button, a single press will get you straight into the auto/manual adjustment. The user has full control over Max and Min temperature settings which allows precise control of the cameras’ sensitivity. Properly done!

Visual Camera

Unlike many entry level units, the 870-2 thermal imager is equipped with built in digital camera. When saving an image, the Testo 870-2 thermal imager will automatically capture both thermal and visual simultaneously. It stores both in a single file (not separately) which I find to be very convenient. The visual image quality is excellent.

There is a compact battery that gives a reported 4 hours of run time, which is impressive for it’s size. Equally impressive is that the unit charges off a USB connection. The battery is also easily accessible if you want to have a 2nd one for swapping in the field.

The thermal imager utilises 1.6GB of internal memory for storing more than 2000 imagesBy connecting to your PC via USB cable, the software automatically engages a download wizard which neatly imports your imagery into data/time ordered folders. As we’ve commented on before, the IR Soft software is awesome.

Both models come with the full professional software suite and 2 years warranty is standard.

So what makes it entry level?

Fixed Focus. Yes that’s right, there is no focus. As I’ve pointed out many times to novice users fixed focus is not a good thing. It’s a cheap thing, it’s a performance limiter, intentionally designed to create the divide between entry level models and more professional ones. While it may seem “easy” to use a camera without a focus mechanism, you will never get a really clear sharp image of detailed or small components. Min focus distance is 0.5 meters, and it makes imaging electrical systems or components rather difficult. The following images are case in point. To perform this kind of inspection you need to be relatively close. The images are blurred, and the detail poor.

Testo 870 Comparison6

Testo 870 Comparison 6

Testo 870 Comparison 7

Testo 870 Comparison 7

View camera specifications & pricing here.

IPI Learning Mastery Series

The Ultimate Guide to becoming an effective thermographer, our Mastery Series includes the following articles:

  • Selecting the right Thermal Imager

  • Resolution and Spot Size

  • Thermal Sensitivity

Click Here to Access