It’s insane how much thermal optics have changed. Over 15 years ago, I had a thermal issue with my M240. It was absolutely massive, and it kind of sucked. Times have changed a lot, and optics like the MARS Mini exist.
The MARS Mini is, uhm, a lot. It’s both a rifle and a pistol optic. Yes, you’ve read that right.
Before we dive into that, let’s talk about the optic itself. The MARS Mini comes from a company called OneLeaf. It’s micro-sized, about 3.37 inches long, and weighs 6.88 ounces.
Even though it’s small, it packs a 640×512 sensor. That size sensor provides an excellent picture, especially for such a small optic. We get clearer images across all ranges, resulting in fewer heat blobs and more defined images.
We have low latency thanks to the 60Hz refresh rate. All of that, and the capability of a rifle or pistol thermal optic for under $2,000.
The MARS Mini From One Leaf
Unboxing the MARS Mini is a little intimidating. A lot is going on in this box. First, let’s address the multi-role design of this optic. It can be used on a long gun or attached to a pistol slide.
It has adapters to mount it on a rifle, as well as both a primary optic and an offset mount to use with another optic. This makes it easy to mount to standard long guns in multiple roles. It can be both a reflex-type sight or a magnified optic.
It has an eyepiece barrel that allows us to conceal the light emitter behind the screen and provides a consistent angle for approaching the optic. The optic comes with interchangeable lenses. Currently, OneLeaf produces 19mm and 25mm lenses.
With the 19mm lens, you get a close-quarters design; with the 25mm, you get a natural .6X magnification, and it’s best used with the eyepiece barrel when you plan to use the built-in magnification.
The digital magnification goes up to 6X.
The handgun mounts include four different plates. This includes a Trijicon RMR adapter, a Leupold DPP adapter, an RMSc adapter, and a Glock MOS plate adapter. You can toss it on your pistol, and now you’ve got a thermal on your chosen handgun.
More Than That
Inside the box, there are three rechargeable batteries, each lasting about three hours. You also get an adapter that lets you use larger 18500 batteries to extend battery life, at the cost of making the optic slightly larger.
The system comes with a USB to recharge the battery and to remove footage that’s stored on the included SD card. You can film your shooting, hunts, or whatever, and remove the footage to watch later.
It also comes with six thermal targets.
I think that might cover everything inside the box. Swapping mounting options takes nothing more than the included wrenches and a little elbow grease. They provide torque specs for each mount, and I would most certainly use a torque wrench to tighten those inch-pounds.
The MARS Mini On A Rifle
I think the MARS Mini works best on a long gun. As a reflex sight, the optic is uber small and compact. It’s a little odd to use a thermal as a red dot. You don’t use a target-focused shooting style like you would with a red dot. Instead, you have to look through the optic purposefully and register the target. It’s not hard, but it’s odd. Regardless, it’s a ton of fun.
Shooting under thermal, especially at night, gives you a unique thrill. While thermals are typically used to detect heat, they can also highlight targets that are colder than the environment.
I like to use frozen water bottles as cheap, easily disposable targets for thermals. Being able to see them in the dead of night and shoot them rapidly, switching from target to target, is a complete blast.
It works pretty well as a primary reflex optic, but I think this setup shines best as an offset reflex sight. Mounting it alongside an LPVO or prism gives you an instant, on-tap thermal sight for both day and nighttime use.
Mounted as an offset, it’s a ton of fun to shoot targets and to be able to identify targets that might be hidden from your normal view. You can get really crazy and pair the offset with a night vision clip-on, and then have total night supremacy on one rifle— a hefty rifle, but still one rifle.
As Variable Optic
I added the eye barrel and turned it from a reflex sight to a variable optic. The eye barrel provides a clear and crisp view through the thermal and a comfortable bit of rubber to rest your eye against.
It’s better to swap to the 25mm lens for use as a magnified optic. Digital magnification isn’t as smooth as analog. The picture distorts just slightly as you zoom in, but remains surprisingly clear out to 6X.
It’s clear enough to see the ears on a rabbit out to 50 yards, so clear enough for a clean shot on most small targets. Speaking of rabbits, the 60Hz translates into smooth movement. Nothing’s jarring, stuttering, or stopping as it moves.
This setup is probably the most useful option for the MARS Mini.
The Smart Aspect
The optic is more than a thermal optic with magnification. It falls into the smart optic territory or is close to it. The optic allows you to pick your reticle from several options, as well as set the optic to first focal plane or second focal plane.
The reticle either grows with magnification or remains a constant size throughout the magnification range. You also have a 1,500-meter laser range finder that’s available at the tap of a button. Additionally, you have a built-in ballistic calculator that you can program with your ammunition information.
This can provide you with an approximate bullet drop based on your information. The MARS Mini only goes out to 6X, so it won’t be something you’d use with a true long-range round, but when paired with subsonic cartridges like the .300 Blackout, it becomes quite handy due to their quick drop.
On A Pistol
You can mount the MARS Mini on a pistol, and it works. However, I don’t have a definite need for this kind of tech in most cases. For handgun hunters, it could be a valuable option for both medium and small game.
On a CP33, it would terrorize small game and pests. On a magnum revolver, it would be useful for deer and similarly sized game. The MARS Mini on a Glock 20 MOS would be a deer slayer if I ever saw one.
On a Glock 17? I don’t see a big need.
Need has never stopped me before, and it’s admittedly fun. However, beyond niche hunting pistols, I don’t see a need for a thermal-mounted handgun. Maybe if I were bringing back the Offensive Handgun program from the 80s, we’d have a case, but I don’t have one.
I appreciate OneLeaf for offering it, even if it’s not my thing.
The MARS Mini In Action
The rear of the screen is actually a touch screen. It allows you to zoom in and swap color pallets with ease.
We get a variety of color pallets, including red hot, white hot, sepia, night vision green, jungle, and ironbow. You can also customize the scene mode for snow, fog, city, forest, and rain to give a clearer picture—plenty of options for you to customize and find the right color combo for you.
At around $1799 for the basic package, the MARS Mini isn’t priced all that high for a thermal. It’s expensive for sure, but when we factor in the performance, the form factor, and the multi-role nature of the optic, its price point becomes a bit more digestible.
It’s exciting to see thermal evolve and become a little more affordable. The MARS Mini is certainly packing a punch in terms of features, uses, and design.
