Does anyone use the Calypso ultrasonic wind meter?

It has 1% accuracy and indicates wind speed and direction. Also interfaces with Strelok Pro. Uses iOS and Android, but the code is open source to adapt.


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I use Strelok Pro on iOS for my long range airgun shooting. I’d been occasionally using my Kestrel 5500 linked with Strelok. I also have the Kestrel Basic Series Vane which I also used a few times but I found it a little clunky to setup. It all worked as designed. But then the Calypso came out, and it looked like something I should try. The Kestrel 5500 has built in weather readings without needing an internet connection. I bought a Kestrel Drop D3 to use with the Calypso which reads wind velocity and direction only. The D3 would give just the weather info that I needed without all the extras of the Kestrel 5500. At first, the Calypso would not link up with Strelok. I updated my iPhone iOS to version 16.2 and then it worked. Weather/rain has prevented me from testing the Calypso in the field, but hope to do so later this month.
 
I use Strelok Pro on iOS for my long range airgun shooting. I’d been occasionally using my Kestrel 5500 linked with Strelok. I also have the Kestrel Basic Series Vane which I also used a few times but I found it a little clunky to setup. It all worked as designed. But then the Calypso came out, and it looked like something I should try. The Kestrel 5500 has built in weather readings without needing an internet connection. I bought a Kestrel Drop D3 to use with the Calypso which reads wind velocity and direction only. The D3 would give just the weather info that I needed without all the extras of the Kestrel 5500. At first, the Calypso would not link up with Strelok. I updated my iPhone iOS to version 16.2 and then it worked. Weather/rain has prevented me from testing the Calypso in the field, but hope to do so later this month.
Following with interest. Especially the Strelok hook up since the Calypso firmware is open source and can be modified. Doesn't Strelok pull the weather data from the phone that it's installed on?

I am in the middle of the city and hard to shoot anywhere but indoors.
 
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Following with interest. Especially the Strelok hook up since the Calypso firmware is open source and can be modified. Doesn't Strelok pull the weather data from the phone that it's installed on?

I am in the middle of the city and hard to shoot anywhere but indoors.
I played with the WeatherMeter wind indicator a little bit and it is working very well with StrelokPro POA to POI calculations. I am using a droid tablet when shooting BR, and the tablet doesn't have a built in internal compass (that is one of the biggest problems I cannot fly my drones with a tablet but must use a fairly smaller cellphone screen).
I like the idea and a small size, but I cannot imagine how the Calipso can "learn" where is your target if the wind is coming from anywhere (let say behind you 40 degrees South or swirling around), and where me have to aim to get the POI in the center.
???
 
… Doesn't Strelok pull the weather data from the phone that it's installed on?
That’s mostly true. The barometric pressure provided by the iPhone to Strelok is the main factor and it seems very accurate. Temperature and humidity are two other factors that the iPhone does not provide, though their contribution to trajectory changes are much less critical. Even so, I wanted all the information that might have the slightest affect.

If your phone has access to internet data, Strelok can use it (Meteo).
 
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I played with the WeatherMeter wind indicator a little bit and it is working very well with StrelokPro POA to POI calculations. I am using a droid tablet when shooting BR, and the tablet doesn't have a built in internal compass (that is one of the biggest problems I cannot fly my drones with a tablet but must use a fairly smaller cellphone screen).
I like the idea and a small size, but I cannot imagine how the Calipso can "learn" where is your target if the wind is coming from anywhere (let say behind you 40 degrees South or swirling around), and where me have to aim to get the POI in the center.
???
You should only need a compass if you are including the Coriolis (and Eötvös) affects. If time of flight is much over 1 second, those can be noticed. That’s after about 300yds for subsonic projectiles.

The Calypso case has a small hole on one side. Though that hole is sometimes referred to as a “dimple” or “arrow” in the documentation. The Calypso should be mounted in the vicinity of your shooting position, with that hole pointed toward your target. That will cause the Calypso to give the correct relative wind direction to Strelok.
 
You should only need a compass if you are including the Coriolis (and Eötvös) affects. If time of flight is much over 1 second, those can be noticed. That’s after about 300yds for subsonic projectiles.

The Calypso case has a small hole on one side. Though that hole is sometimes referred to as a “dimple” or “arrow” in the documentation. The Calypso should be mounted in the vicinity of your shooting position, with that hole pointed toward your target. That will cause the Calypso to give the correct relative wind direction to Strelok.
Mounting it upside down on your rifle (see photo above) should work in theory. It does not need to measure wind from behind you. Coupling your Strelok Pro or ATN scope with speed input (like from an FX Chrono) should give you a complete shooting solution (in addition to the Calypso). I think the ATN scope already has all the baro and temp data.
 
Mounting it upside down on your rifle (see photo above) should work in theory. It does not need to measure wind from behind you. Coupling your Strelok Pro or ATN scope with speed input (like from an FX Chrono) should give you a complete shooting solution (in addition to the Calypso). I think the ATN scope already has all the baro and temp data.
Mounting the Calypso on the airgun would make it very convenient to use. But some of my targets are far away and sometimes inclined up a hillside. I ordered a light stand that I can extend (up to 13’ high) to better have the Calypso up in the airstream.

Also, it could be useful to know if there is a tailwind. At 300m, a 5mph tailwind moves the POI up over 1moa (3.5”).

I also have an MTC rangefinder that can pass target distance data to Strelok. Though my targets are stationary, so unlike wind data, it only needs to update once when I switch to a target at a different distance. And Strelok passes the updated holdover/click data back to the range finder view screen and also audibly on the included earbuds, if you choose to use them.
 
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The wind at my location is alwways present (Ontario, between Great Lakes), swirling and pulsing. I am shooting 100 meters BR and the wind can really mess with mind :)
I shall make a video one day at my gun range to show the Strelok POA screen how the dot is bouncing around. :)
I have learned that heavier wind indicator blades with long wind tailes are much better, also played with the button in Strelok to slow down the bouncing.
 
Mounting the Calypso on the airgun would make it very convenient to use. But some of my targets are far away and sometimes inclined up a hillside. I ordered a light stand that I can extend (up to 13’ high) to better have the Calypso up in the airstream.

Also, it could be useful to know if there is a tailwind. At 300m, a 5mph tailwind moves the POI up over 1moa (3.5”).

I also have an MTC rangefinder that can pass target distance data to Strelok. Though my targets are stationary, so unlike wind data, it only needs to update once when I switch to a target at a different distance. And Strelok passes the updated holdover/click data back to the range finder view screen and also audibly on the included earbuds, if you choose to use them.
300m? What airgun do you have? o_O
 
The wind at my location is alwways present (Ontario, between Great Lakes), swirling and pulsing. I am shooting 100 meters BR and the wind can really mess with mind :)
I shall make a video one day at my gun range to show the Strelok POA screen how the dot is bouncing around. :)
I have learned that heavier wind indicator blades with long wind tailes are much better, also played with the button in Strelok to slow down the bouncing.
Yes, Ontario (Ottawa) down to Watertown, NY is in that path of unpredictable and nasty cold wind coming from the Great Lakes. Some say it feels colder than up north at the Hudson Bay.
 
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300m? What airgun do you have? o_O
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That is a MONSTER! I read through the thread... Amazing build and congrats on the placings. Now doubt you need the wind that accurately. Good luck at the next ELR!