Back in June, we took a look at some FLIR handheld thermal imagers. Afterward, FLIR offered to send out their PTS536 ThermoSight Pro for review. We got a preview of the FLIR ThermoSight Pro weapon sights during SHOT Show range day last January.


    PTS536 mounted on a Remington 700CP

    FLIR PTS536

    The PTS536 has a 50mm germanium objective lens and powered by FLIR’s Boson core. It has a 60hz refresh rate so no issues of lag. Features wise it is very similar to the FLIR Breach in terms of menu and controls.

    At the top of the PTS536 is your control pad. It is a standard + shape button layout with a main button in the center.

    Here is what the buttons do.

    ▲- Press to increase screen brightness. Hold down to change image palette.

    ▼- Press to decrease screen brightness. Hold down to change image palette.

    ►- Press to change digital zoom 2x, 4x, and 8x. Hold to turn off reticle.

    ◄ – Press to change reticle color. Hold to change reticle design.

    Just above the eyepiece and behind the control panel is the on/off rotary switch.  On the side of the 536 is a Picatinny rail for an external battery pack and the USB-C port for powering the unit or downloading any images and video it recorded.

    The battery compartment is on the other side. There is a large circular cap with large ridges so you can remove or tighten the cap with thick gloves if you had to.

    Other than running an external USB power supply, the 536 is powered by two CR123 batteries for four hours.

    Thermal Vision Through The PTS536

    During the day time, the PTS536 has a tough time determining what is hot. The ground is hotter than people. See the images below. The tires of the side by side are the hottest part as well as the engine.

    The resolution is not that freat upon first impression. That is mostly due to the noisy image. Look at the photo above. Look at the ground which appears gray. There is a considerable amount of grain in that image. It does not look clean.

    I tested a DIY method for zeroing a thermal device. I used aluminum foil tape on cardboard. The thin aluminum foil tape will heat up in the sun faster than the cardboard, as seen below.

    The PTS536 was able to detect the steel targets set at 1000 yards (at the bottom of the crosshairs) and the 1100 yard target near the top of the crosshairs just a little bit to the left. I took these images the same time I reviewed the Pulsar XP50. So the time, location and temperature is the same. The steel targets are painted white and reflect heat rather than absorb it. So the ground is actually hotter than the steel targets.

    The photos below were taken at 11:30pm near Napa Valley.

    Black Hot palette almost looks like a black and white photo. Look at the truck below.

    Cons With The PTS536

    One issue I had with the PTS536 is that it starts at 4x magnification. So any small movement is exaggerated in the video recording. See the video below which is a highlight reel of my testing with the PTS536.

    It was not clearly indicated in the video above but I was able to hit steel at 1000 yards. The problem is more me and the gun than the PTS536. I could clearly see the steel and in some cases see dirt get kicked up to make corrections. The reticle options are rather plain and not very exciting.

    The reticle choices are not great especially when you want to shoot farther and have to adjust for ballistic drop. There is not much to reference off of to make accurate shots at distance.

    Pros With The PTS536

    The 536 came with a wireless remote that mimics the same functions as the control panel on top of the 536. This is rather handy if you want to zoom in or need to change reticle colors on the fly. Or even capture images and video on the fly without having to shift your support hand to reach the top of the unit.

    Another cool feature is the recoil activated recording. I did not turn it on but it must have been selected prior to me receiving this T&E (Test and Evaluation) unit. I was helping the guys at CROM USA test fire their first customer ordered CR-7, a semi-auto .338 Lapua Magnum AR.

    Unbeknownst to me, the PTS536 recorded all the shots I took with the .338 Lapua Magnum.

    Final Thoughts

    The price for the PTS536 is not terrible at an MSRP of $3,795. It is more affordable than other thermal sights I have tested in the past. I did find 4x optical magnification to be a little too much. It makes it hard to scan your environment and I feel I would need a 1x handheld to compliment the PTS536. The detection is similar to other thermal sights but the image clarity is not as clean. The choices of reticles are fine for shooting within 200 yards but leaves much to be desired for shooting further and having some reference for ballistic drop compensation. The FLIR PTS536 does not have any audio recording. Which was also seen in the FLIR Scion and FLIR Breach. This is a bit of a downer for me. I do not think there is a microphone on the FLIR PTS536.

    Would I buy a PTS536? I am ambivalent. It is a rugged design and it clearly works but there are some features I do not like. If you are happy with a fixed 4x image and do not need a 1x thermal device for scanning then it is cheaper than the compeition. But if you compensate and buy a thermal handheld scanner then you conceivably are spending just as much money as some of the higher end thermal sights but you still cannot record audio with the Flir. If they were able to add audio recording and clean up the image then I would like the PTS536 more.

    For more information on the PTS536 check out their website.

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    Nicholas C

    Steadicam Gun Operator
    Night Vision & Thermal Aficionado
    Flashlight/Laser Enthusiast
    USPSA competitor

    Any questions please email him at [email protected]