kestrel Baro pressure/altitude

[cj8vet]

I,ve searched and read thru threads but am still confused. If I set my kestrel ref alt to "0", and turn it on at the local airport the kestrels baro and station pressure are still diff than the airports AWOS reporting.(not close) AND do you leave sync ALT off or on?
Thanks
Mark

 

[moondog]

Go to the airport and set the reference alt. Of the airport to your Kestrel

 

[boltfluter]

Most likely the reported pressure for the airport is corrected to sea level. My Kestral gives me pressure at the altitude I am standing at. Unless I do not understand your question. Just a thought.

Paul

 

[338 dude]

Most likely the reported pressure for the airport is corrected to sea level. My Kestral gives me pressure at the altitude I am standing at. Unless I do not understand your question. Just a thought.

Paul

Station pressure

 

[FeMan]

I believe you leave the sync "on", otherwise it thinks you are the same place/condition as you were when you turned it "off".

 

[Uthink Uknow]

Leave the sync on and really doesn’t matter what the altitude is when you set it as long as it was used as the base for all your computations. So, set it at home and leave it at that as long as you know the ball park altitude at your house. If it must be re-set just do it at home again and you are back where you started. It works well for me.

 

[memphistransplant]

The altimeter setting reported on the AWOS is pressure altitude corrected for temperature and humidity, which changes often, which is why it is reported on the AWOS. The airport elevation, of course does not change. I'm not sure how the Kestrel calculates altitude or barometric pressure.

 

[Uthink Uknow]

Density altitude changes constantly but it is based on the reference setting for altitude you enter into the Kestrel. That is why you need a base altitude figure that is easy to work off of.

 

[hogpatrol]

Somewhat OT, but with the Applied Ballistics program, it pulls the data from the local station and uses that density altitude in it's computations. I used it in South Africa and when I went from the trajectory table back one page, density altitude was more than 2000 ft above the MSL elevation. This is with an android phone.

 

[243Mendoza]

I,ve searched and read thru threads but am still confused. If I set my kestrel ref alt to "0", and turn it on at the local airport the kestrels baro and station pressure are still diff than the airports AWOS reporting.(not close) AND do you leave sync ALT off or on?
Thanks
Mark

You set the ref alt at the value for where you are located. If you don't know that alt, look at a google maps to get an idea. If the weather hasn't change, then when you drive to a different location, then kestrel should read the correct alt at the new location.

 

[cj8vet]

Thanks guys, what I was really wondering and have found out--it really doesn't matter what you do on the weather side of the unit-it does ballistics based on what it reads where you are-- Please correct me if I am wrong?
Mark

 

[243Mendoza]

Thanks guys, what I was really wondering and have found out--it really doesn't matter what you do on the weather side of the unit-it does ballistics based on what it reads where you are-- Please correct me if I am wrong?
Mark

The best technique, at your shooting location, is to input the elevation of your shooting location as 'ref alt' and the atm pres and density alt readings should be good at your shooting location.

 

[Gil P.]

Thanks guys, what I was really wondering and have found out--it really doesn't matter what you do on the weather side of the unit-it does ballistics based on what it reads where you are-- Please correct me if I am wrong?
Mark

You're correct. Don't enter information from a nearby weather station into your kestrel. Your kestrel is a weather station. Use the altitude the kestrel gives you, and use "station pressure". The station pressure is the pressure the kestrel is reading from wherever its at and is the best pressure reading because it's right where you are standing.

 

[MS50]

Barometric pressure is adjusted to sea level. Station pressure is local pressure not adjusted to sea level, but a reference altitude of zero. With a reference altitude of zero, the Kestrel gives you the pressure at your location. I'm not familiar with the ballistic calculator in the Kestrel. There's probably a setting that calculates scope settings based on local pressure. I use Shooter App, there's a setting to use local/station pressure and temperature.

 

[avidflyer]

Thanks guys, what I was really wondering and have found out--it really doesn't matter what you do on the weather side of the unit-it does ballistics based on what it reads where you are-- Please correct me if I am wrong?
Mark

CORRECT.....

 

[Uthink Uknow]

You are using your kestrel for different reasons than I am. I am tuning a load for the season and at different locations all summer. Therefore, I tune at Altitude 640 feet and with density altitude reading 2100 feet. For instance. And my tuner is set at let’s say 11:45. Now all summer I write density altitude at all these ranges in all kinds of weather All over the U.S. The kestrel adjusts for all these conditions and I turn the tuner to what works at density altitude of 2800 feet. I don’t care what altitude I’m at; all I need to know is DA and the tuner setting that works at 2800 DA. Ballistics be damned, I want the bullet hole in the paper where I want it to be.

 

[243Mendoza]

From the Kestrel website:
Let's assume you know your altitude.

Scroll through the Kestrel meter to the Baro screen. It is here where you will adjust your 'reference altitude'.

Kestrel 3500 and below: Push the 2 outer buttons to adjust
Kestrel 4000 and above: Push the middle button, go to reference alt and move arrows left and right

Now, read the barometric pressure it gives you. That will be your reference pressure. Go to the Alt screen, and adjust the Reference Baro (Ref Baro) doing it the same way as above.

As you are doing that, you will notice that the altitude reading will change as your reference pressure changes. When you are finished, press the center button to exit the adjustment mode.



To adjust the barometric pressure first, first you will need to obtain your altitude from a topographical map, landmark or the Internet. Once you have that number, scroll to the "Baro" screen which is your urrent Barometric Pressure on your Kestrel. Once there, press the center button to enter the adjustment mode.

Again, use the left and right arrows to adjust the reference altitude. Again, you will notice that the Barometric Pressure will change with changes in the reference altitude. When you are done, press the center button to exit the adjustment mode.