Thermal Scope Refresh Rate: 25Hz vs 50Hz for Moving Game
"Does refresh rate actually matter?" comes up whenever two thermal scopes look identical on paper except one is 25Hz and the other is 50Hz. The short version: it matters most when your target is moving and you're swinging the rifle to follow it. This guide explains what refresh rate is, what 25Hz, 50Hz and 60Hz feel like in the paddock, and when paying for the higher number is worth it.
The short answer
Refresh rate is how many times a second the thermal image redraws, measured in hertz (Hz). A 50Hz scope updates the picture twice as often as a 25Hz one, so fast-moving game like running pigs, foxes and dogs looks smoother, with less blur and lag, and the picture settles faster when you pan. A 25Hz scope is perfectly usable for sitting and watching and for controlled scanning, and it often trades that speed for longer battery life. If you mostly shoot moving game off-hand, 50Hz is worth it. If you spend most of your time glassing and waiting, 25Hz is fine.
What refresh rate actually is
Every thermal builds a new frame from its sensor many times a second and pushes it to the display. Refresh rate (sometimes called frame rate) is that number. Hunting thermal scopes typically sit between 25Hz and 60Hz, with a few newer units higher again. It's separate from sensor resolution, pixel pitch and NETD. Those set how much detail and sensitivity you get. Refresh rate sets how smoothly that detail moves.
25Hz vs 50Hz vs 60Hz in the field
| Refresh rate | What you notice | Best for |
|---|---|---|
| 25Hz | Smooth on still scenes. Some blur or slight lag on fast movement and quick pans | Glassing, fox whistling, controlled scanning, longer runtime, value |
| 50Hz | Noticeably fluid on running game. The picture keeps up as you swing | Moving pigs and foxes, off-hand and walked-up shooting, general all-round use |
| 60Hz+ | The smoothest motion and fastest pick-up of the target again | Fast, reactive shooting and demanding tracking |
The difference is real but it's not magic. On a stationary animal across a paddock, 25Hz and 50Hz look much the same. The gap opens up the moment the animal runs and you have to track it. At 50Hz the picture redraws often enough that the target stays crisp. At 25Hz a fast pan can smear briefly before it catches up. Higher refresh also tends to be easier on the eyes over a long night.
Does a higher refresh rate cost you anything?
Sometimes. Pushing more frames can draw a bit more power, which is why some value-focused models run 25Hz to stretch battery life and keep things simple. So refresh rate is a balance, not a "bigger is always better" number. Weigh it against runtime, the rest of the spec, and how you actually hunt. It's one factor among several, not the headline on its own.
How to choose
Check the refresh rate on the spec sheet alongside the sensor, lens and NETD, then match it to how you hunt:
- Mostly moving game (pigs, foxes, walked-up). Go 50Hz or higher for blur-free tracking.
- Mostly watching and deliberate shots. 25Hz is genuinely fine and may give you more time in the field per charge.
- Not sure. 50Hz is the safe all-rounder. It handles both without compromise.
Whatever the Hz, remember it doesn't change how far you can see or how much detail you get. That's down to the objective lens, resolution and pixel pitch.
FAQ
Is 25Hz too slow for hunting?
No. 25Hz is fine for glassing, scanning and shots on stationary or slow game, and it often comes with better battery life. It only starts to show its limits when you're tracking fast-moving animals and swinging the rifle, where 50Hz looks noticeably smoother.
Does refresh rate affect how far a thermal can see?
No. Detection and identification range come from the objective lens working with the sensor's resolution and pixel pitch, not the refresh rate. See our guide on detection range and lens size.
Is 60Hz worth it over 50Hz?
For most hunters the jump from 25Hz to 50Hz is the one you feel. 50Hz to 60Hz is a smaller, more subtle gain that matters most for very fast, reactive shooting. Don't pay a big premium for it unless the rest of the scope already suits you.
What else should I weigh up besides refresh rate?
Sensor resolution and pixel pitch (detail and field of view), objective lens (reach), and NETD (sensitivity in poor conditions) all shape the image. A balanced scope beats one that's strong on a single number. More in our 384 vs 640 guide and NETD explainer.
Related: Detection Range and Lens Size, 384 vs 640 Sensors, Why Digital Zoom Degrades Your Image, How Thermal Imaging Works, Thermal Scopes and Best Thermal Scopes 2026.