Tricks to "see" the direction/angle of the mirage

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Black Jack

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Hello guys, for those of you who use mirage to find wind speed. I read and try to understand reading the mirage. I am focusing on my target--> then back out the focus to somewhere halfway and try to see the mirage.

I can see the waves of heat going up but cannot get the direction of those waves to guesstimate the angle and then find a wind value. Is there some kind of trick to see that?

Trying to find video of it but didn't find any at the moment. Is it just to keep on looking and will eventually "find" it like in the MATRIX? :) Tks
 
Wind reading book by Miller and Cunningham... my goto wind "understanding" resource. Contact MILCUN and chat with Linda.

If you see the mirage rising, then you are looking either directly into the wind or there is no wind speed.

Go out on a windy day and if the mirage is visible, you will see it burble laterally in the direction of the wind.

Or watch any good spaghetti Western and you will see the mirage rolling along usually in some dramatic scene.... hero slumped over his horse, etc

Quantifying mirage follows the ball park rules you will find in many resources including that book... being good at quantifying the mirage.. Well, that is alot of time looking at it, sending lead down range and trying to understand what you did wrong...

Depending on the focus system on your scope, you will be able to see the air at several distances so you can literally move back and forth over your range and see how the air is moving. In my opinion, the Sightron SVSS has the best side focus system for doing this... but many top tier optics do this well too.

Jerry
 
I was trying to do it with my spotting scope. It's an older Bushnell model. Like I said, I can see there is some mirage but can't "see" the direction it's moving. I put a flag in the middle of the field

and I know there was a left to right wind of approx 5-8mph....but couldn't make it out with the mirage. Trying to understand the wave and how it works :( for when I do not have flags to help

me out. Or at this time of year, when there is no foliage to read the wind. Tks
 
Then you have the wrong "glass"... there are plenty of spotting scopes and scopes that are very good at picking up the mirage.

Try putting out a saw horse or plywood board with a straight edge at the top. Then you have a reference to view the "wobbly" against. With the humidity present, mirage should be real easy to see.. at Connaught, we literally lost a 6 ft square target cause the mirage was so bad.

Play around with the eye piece focus (if present). Some of the best glass for mirage viewing were from Bushnell Elite spotters from years back. Not sure what you got but maybe the spotter just isn't what you need????

Jerry
 
So anything with a horizontal line should be good to compare towards my flag? Than try to see it from that relation. Tks I will try that.

My spotting scope is an old sentry. Maybe it's not good enough to see it but it's probably me.
 
Flags (or grass, trees, wet finger etc) can be used to determine direction. (If there are several flags, find one blowing straight at you, or straight away, that's a perfect direction flag). However, if you can see mirage and it's not "boiling" (straight up), turn your spotter slowly until you see it "boiling", and that will give you direction. The problem is, by the time you figure direction this way, IT'S CHANGED. A fishtail, 11 o'clock to 1 o'clock is the worst. You've calculated 7 mph from 11 o'clock, set your sights, take aim, it's switched to 9 mph 1 o'clock, fire and you've missed the target. Don't get discouraged, it takes time to learn the wind.
 
I'm thinking that putting the optic closer to the ground will help see it. So prone on a rifle it will show more than standing on a tripod.
 
My experience is pretty much flat range, gallery type shooting and I was usually able to see the blades of grass on a firing mound between my position and the targets to confirm I had the spotting scope focused “back” from the target.

A low speed wind mirage should appear like the slow current of a river. David Tubb used the analogy of watching water flow through a glass pipe, and someone is turning the faucet up and down.

A boil will be hard to distinguish any direction as it appears to “boil” straight up and is generally indicative of a no wind, or changing wind direction. This is also when the images beyond your focus will be distorted the most and may appear to “dance” or wobble

It’s possible that you may have been watching on a day where the speed was high enough that the mirage runs almost flat and is hard to see. Above certain speeds it becomes harder to see subtle increases and decreases in speed.

As others have noted the quality of the scope makes some difference in clarity, and keeping it close to the ground helps.
 
In some places the mirage is much easier to see than in others. When I shoot silhouette in Heffley Creek we have a grassy range that slopes uphill. Very often there is little mirage to see. Usually the best place to see it is on the silhouette rails. When I shoot in the states on some of the hot & dry ranges, the mirage is so thick you can't miss it. It is much easier to read there. I also use a Bushnell Ultra Legend HD spotting scope. When compared to a good Kowa scope it is not quite as good at picking up subtle mirage but it is very very close.

One trick that I have not ever tried, but read about in Jim Owen's book, is to turn the spotting scope as you look down range. At a certain angle the mirage will go to a boil. The scope is now pointed directly into or away from the predominant wind. Our matches don't have time for this sort of tomfoolery or I would have tried it. The concept makes sense to me.

Chris.
 
Hope this helps

http://southtexasshooting.org/multimedia/text/mirage.html
miragewind1701.jpg
 
To read mirage its best to focus on something short of the target. That way you get to see deeper mirage both before and behind the plane in focus.

Keep in mind that reading mirage has it's downfalls that you need to watch out for.

For example... intermittent cloud cover....

When the sun is shining mirage will look heavy, then a cloud rolls in and mirage is suddenly gone. If you don't notice you will assume the wind died and lay off the windage, but that's a mistake.

Furthermore, in the cloud cover there is a vertical offset that will occur up to about 1/2 MOA. So when the cloud rolls in hold low about .25 to .5 MOA depending on cloud density.

Here's a video showing how mirage appears to move the target.

It obviously doesn't actually move, but how do you know where the target really is?


A guy could always use a similar setup as in this video but put a phonescope on the riflescope spotting scope and orient it to the left while shooting.

That way you could aim where the spotting scope reticle is pointing regardless of where the image has refracted.
 
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