After watching the news about the new AGM Evolver LRF 1280 coming in at just $7K, i was going to jump on it. And then I saw the refresh rate. A measly 25Hz. If it would increase refresh to 50Hz when zooming to 640 resolution, I could still be interested. But 25Hz is just way too slow IMO to hit anything on the run.

Nonetheless, it’s nice to see the higher resolution thermals coming down in price.

More sensor elements means slower scan or higher horsepower processor.

I'll bet 25 Hz is just fine. It wasn't that long along that 30Hz worked fine with 640 cores. Then the 384 cores came out and 50Hz was used to keep them from being choppy. I'll bet it has something with power consumption as well. Sometimes I have to remind myself my work thermals use 400Hz and 50Hz is okay for my hubting thermals.

Yes, it’s also a heat dissipation issue. I remember when CMOS became the default for still cameras but couldn’t be used for video frame rates because of heat. Eventually, they solved the issue with CMOS for video but it also ushered in its own set of problems due to being read sequentially vs. all at once with a CCD sensor. I am very familiar with the inner workings of video cameras.

25hz is just above the level that most humans can readily detect the stop action jittery movement. Many of the old Hollywood movies were at 25 frames per second. Film was expensive.

Where the slower rate will show itself most is on fast moving animals at shorter distances, fast panning, and in trying to do slow motion reviewing

I would like to see one in person to see if they really have beat processor lag that has plagued previous 1280s. Maybe that is where the 25hz comes from.

But yeah, in looking at the videos posted so far, the frame rate will hunt. The resolution should offer some nice clarity for identifications at distance.

Thermals are not video cameras. Think of the Germanium lens as a filter. it filters out light normally in the 8-12 micron range. Newer stuff has a broader ranger for better sensitivity and definition. It is then focused onto the detector which turns them into electronic signals that in turn input screen in which you see. It's much more complicated than that, but you get the basic idea. You want a really good image, cool the detector to 80 kelvin.

For $12k, I'd think there wouldn't be any technology left out. But what do I know...I bought my only thermal used for $2k (super hogster a3)

"cool the detector to 80 kelvin." 20 Kelvin is much better.

Close, they were shot at 24fps, with a 180 degree shutter (the film was exposed for 1/48 second per frame). In the theater, 2 things that helped create smooth motion were, 1. Low light levels which used our persistence of vision and 2. Each frame of film was shown twice with a 1/48 second shutter on the projector.

I have no doubt, having already looked at some of the video on YT, that the higher resolution will greatly aid ID at distance on nearly motionless animals.

Many cameras, like GoPro, iPhone and others will allow for faster frame rates by lowering resolution, thus keeping the load on the overall system somewhat constant. Which is why I made the comment that it would be really cool if the Evolver could increase frame rate while digitally zoomed in, or even offer a setting for 640 res at 50Hz if you don’t need the extra clarity.

Not sure about this particular optic, but the human eye can definitely detect the difference far above 25hz. I have a 240hz monitor and when I go down to 30-60hz just watching the mouse movement makes me a bit nauseous, looks terrible.

Resolution will help ID, as GNTX said, but the refresh rate is what is going to keep the image from tearing or stuttering in my experience.

50Hz standard is what most of the world uses (power and video) and as this stuff is made elsewhere, that's what we get. Setting the scan rate slower can increase the 'sensitivity' for uncooled sensors - cool more between scans.

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It is a balance of performance vs. cost. To hit a certain number, they have to spec out components that will allow them to sell the finished product for that number. Higher spec components cost more because they typically have lower device yield ( I worked in the semiconductor industry for many years before starting my own video production company). Kind of like diamonds. There are tons of them, but few of them are flawless ones that fetch the high prices.

Limiting the frame rate to 25Hz is a way to keep the heat dissipation (and battery life) manageable with the component specs they chose to use. But they could engineer into the design, a toggle that lets you choose to step down to 640 res and double frame rate to 50Hz. It’s called subsampling the sensor.

Where do you work Jhop? At Raytheon, we used cryogenic cooled detectors on the thermal section of the MTS units.

Liquid Neon works mo better.

How about Liquid Helium?

For what it's worth, I've had the AGM Evolver 1280 for over 3 months and I'd have lost 100% of the money in my bank account on a bet that it was any less than 50hz refresh rate. When we saw the specs at SHOT last week that said 25hz we just knew it had to be a misprint. We were blown away to learn it's a 25hz because to our eyes, we'd never know it.

We were given some information that was a bit above my paygrade but it sounds a lot like what GNTX was saying. We're being told with this ultra HD sensors you can use a lower refresh rate. I'm no electrical engineer but I've seen a few thermals and this one looks fantastic. I've let multiple other people with a lot of thermal experience use it and no one has noticed anything unusual.

After getting back from SHOT I took the Evolver 1280 out in the field and put i side by side with another 1024 50hz optic and I could see no difference between them in lag, refresh etc Granted this is a pre-production model Evolver but I can't imagine the final production models will be worse than a pre-production model.

So for what it's worth, I'm very impressed and I personally chalk this up to my old saying "you can't judge a thermal by it's specs".

I'll try to explain what I'm thinking about this refresh rate business: it has me thinking along the lines of the way we evaluate internet speeds.

There's the data rate, and there's latency.

Internet performance has improved so much over the last 15 years that we are hardly even aware of speed issues anymore, but the time lag in getting the image to the eye would be the equivalent of latency.

If you run a speed test on your internet connection, you may be getting very high data transfer speeds but still find yourself waiting for some period of time (however brief) for the transfer to begin. That is latency.

Consider two scenarios, two different internet connections:

A: 950 MBytes/second, latency 250 milliseconds

B: 250 MBytes/second, latency 50 milliseconds

Connection B could very well appear to be the higher performing connection simply because of your perception. It's not getting the data in front of you at the rate Connection A does but both rates are so high that your eye cannot see the difference. Excessive lag, on the other hand, is easily perceived.

Maybe this makes some sense to some of you more techie types. Maybe not...it's just my intuitive perception of all this.