REVIEW: TOPDON TS004 Thermal Monocular

As thermal imaging technology continues to expand into the general consumer space, astute outdoors enthusiasts and home defenders are taking advantage of the newest crop of effective, price-conscious products coming to market. The latest is the TS004 thermal monocular from TOPDON.

by Rob Reaser

A quick search for thermal optics reveals a sizeable field of manufacturers offering everything from advanced rifle scopes that can set you back a significant percentage of your annual salary to simple hand-held monoculars that easily fit the budget of those willing to forego a few “eat-out” sessions. We have been testing several of the newest thermal options over the last year because their value has become ever more relevant to the lifestyles of Shoot ON’s hunting and defense-minded readership.

Most recently, a friend tipped me off to the latest manufacturer to enter this increasingly crowded consumer segment.

TOPDON is a global producer and technological innovator of automotive diagnostic tools as well as thermal imaging solutions for mechanical and industrial applications. Given the growing interest in thermal use for outdoor recreation, wildlife viewing, and home security, it is no surprise that TOPDON saw an opportunity to leverage their thermal imaging expertise to step outside of the automotive/industrial categories. The company’s opening salvo into this new territory is a thermal monocular that satisfies the basic needs of identification beyond the human’s visible light spectrum and do so without breaking the bank.

The TOPDON TS004

The TOPDON TS004 is not unlike most entry-level thermal monoculars in the outdoor marketplace. It is a handheld unit weighing around 11 ounces and measuring about six inches long (sans the rubber eyepiece). The TS004 is powered by a 5000 mAh rechargeable battery and comes with a wrist lanyard, USB-A to USB-C charging and data transfer cable, a carry bag, and the requisite quick user guide. The unit is also supported by TOPDON’s Topinfared app, allowing wireless connectivity to your Android or Apple mobile device.

You can get the TS004 direct from the manufacturer for $449. Thermal monoculars in this price class are relatively limited when compared to the $1,000+ offerings, with the primary market competitors for the TS004 being ATN, AGM, InfiRay, and Konus.

The tactile operation of the TS004 is about as simplified as it gets — and that is something I have come to appreciate over the month or so that I have been evaluating this device. All digital controls are positioned across the top of the ergonomic housing. The large control buttons are easy to locate in the dark and concave in profile for positive engagement.

What I really like is that, in standard operation mode, the two rear buttons serve only their designated functions — magnification control for the one and image recording for the other. With some thermal units I’ve tested, the control buttons are multi-functional and sometimes a challenge to locate by feel. I may want to increase magnification, for example, and accidentally hit the menu or photo button; or, one button may serve two different functions, so you must activate the correct setting to get where you’re going. With the TS004, there are no such issues. And since the magnification and image capture functions are all that I really use in the field, this is a practical and efficient setup.

The menu button does serve two functions, but here, also, there is no confusion. Single-pressing the button allows you to quickly change the color palette between the five color profiles: white hot, black hot, red hot, fusion, and bird.

This deer stood about 25 yards as I took pictures using the white hot, black hot, red hot, and fusion color profiles. There is also a “bird” mode, intended to enhance avian visibility. It works, but I found it to be too dark for standard viewing. Note that the picture-in-picture (PIP) feature is activated in these images.

When you do want to access the menu to activate the PIP feature, switch between still photo capture and video, or change any of the settings, just long-press the menu button for three seconds. From there, the magnification and imaging buttons provide the up/down scrolling through the menu.

Another welcome feature of the TS004 is its wireless live streaming and control capabilities via your mobile device. I found downloading and installing the Topinfared app to be painless. The only hiccup I had was getting my phone to connect with the TS004, but that turned out to be totally my fault because I denied the app a couple of permissions during the installation. Click “accept” for all the requested permissions and the wireless communication unfolds effortlessly.

Once you are connected to your mobile device, you have full wireless control of the TS004. This is especially handy during long observation periods when employing a tripod. Speaking of tripods, the TS004 includes a standard ¼-20 threaded bushing in the bottom of the housing to accept a tripod adapter.

Here is the Topinfared user interface (left). As you can see, it provides access to all the key functions, including still image and video recording. This is great for hunters or wildlife viewers because you can manage the operation discretely without having to be hunched behind the unit. The app also gives access to the photo and video galleries (right) to easily review your imaging results.

TOPDON keeps their TS004 performance claims real. The 13mm objective lens works with a 640×480 liquid crystal on silicon (LCOS) display and a 256×192 resolution IR detector to provide target detection out to 450 yards and target recognition to 100-yards. The above left image shows a barn at 207 yards distance. The deer bedded in the field are 100 yards away. For pretty much any homestead protection or hunting scenario, the TS004 delivers on its performance claims.

You’ll notice that the magnification on the left photo is 1X. The TS004 has a digital 2x power factor, with magnification at 1X, 2X, 4X, and 8X. The squirrel hugging the tree in the right-side photo was about 10 yards distance. With the digital magnification at 8X, it nearly fills the frame, and the resolution makes the subject easy to discern.

The TS004 is built for the outdoors. The housing is of a rugged design and composition. I can’t tell if the chassis features a hybrid type of rubberized armor coating or what, but the surface definitely has “grip” and delivers a solid purchase in the hand. The unit boasts an IP67 environmental rating, which means it is protected from dust intrusion and is waterproof against heavy precipitation.

You’ll note the small lens above the larger objective lens. This is an LED that is activated when the TS004 is powered down and you depress the menu button. You’ll not be using it to find your way home in the dark, but it is good for closeup work.

One of the greatest advantages of a thermal monocular for the hunter is, in my opinion, its ability to help you locate downed game animals during challenging tracking jobs. Those of you who have trailed through brushy or grassy terrain after dark know exactly what I’m talking about.

A few years ago, I made a perfect arrow hit on an Oklahoma whitetail that left nary a drop of blood to follow. The deer climbed out of a creek bottom and into a grass-choked open area, leaving nothing to follow. Fortunately, we had a tracking dog that made short work of locating the buck, but it underscores the point that a thermal unit was exactly what we needed had the dog not been available.

A few days ago (as of this writing), I was fortunate enough to bag what I’m confident will be a Pope & Young book whitetail (I’ll know for sure after the drying period). Although I knew the buck was on the ground (having heard the crash), since I had the TS004 with me, I wanted to simulate searching for the deer with the thermal. The TS004 easily picked out the downed buck through the tangled understory. Had this been a difficult tracking job — and I’ve been on many — it could have been nothing to walk right past the deer and never know it. With a thermal, you’ll be hard-pressed to miss it.

Of course, the real validation for a handheld thermal like the TS004 is its homestead security function. Whether you are in the suburbs or live on an isolated patch of rural America, being able to detect what goes bump in the night well before the “bumper” knows you are onto him is a priceless asset. Maybe it’s just critters in the trashcan, but maybe it’s a two-legged varmint. In either case, having a thermal unit to identify what’s going on before the culprit knows your location gives you the tactical upper hand.

And for that alone, I feel the $449 TOPDON TS004 is well worth the price of admission.

TOPDON TS004 Thermal Monocular Specifications