Reading mirage

[DannyS]

Mozzie, I don’t mean adjusting the scope between shots, I mean set it on a low power and shoot it on a low power, a power at which you can see the mirage easily.

[Mozzie]

Danny
Sorry my mistake. But I do like using all of the NF competitions power, I have backed off on many occasions to 30x to lesson the mirage blurr, but now I want to try and tame it and read it to my advantage.

[DenisA]

G'Day Mozzie,

You asked for it………………………

This is a topic that is dear to me in F-class. Something I've been working on for the last few years and something that I attribute highly to a huge improvement in my own game.

I shoot FSTD using a spotting scope setup ALWAYS. I rely on the mirage for more than 90% of my wind calls. My decisions aren't solely based on mirage, but they always include the info I get from the spotting scope. Each call is based on flags then spotting scope mirage then rifle scope picture.
I couldn't tell you the actual speed of the wind for different mirage pictures as I rely on the sighters to give me that info. I don’t want to PRETEND I know, I don’t want any pre-conceived ideas of wind speed, I just want to know what this condition is doing to my bullet NOW. Using all 3 indicators is a bit like a GPS system triangulating a position and reducing error. The more satellite’s you have the less error. Well, the more wind indicators you have that are quick and easy to access the less error. If the flags look the same, the mirage looks the same and the scope picture looks the same, you can feel VERY confident that your shots going to be consistent with the last.

1st. Flags first. Not much to explain here that most shooters don’t already have an understanding of. Flags are the most obvious indicator of gross wind velocity and direction.

2nd. The spotting scope info is only about the velocity, direction, shape and clarity of the mirage. Interestingly I’ve found that another great indicator is the movement of the actual scope. Sometimes we get so wrapped up in what’s happening down range that we forget to check what’s happening at the mound and behind us. When the spotting scope starts moving around from the wind, even a little, it’s a great time to stop and let it settle to where it was in the sighters. That’s normally when you realise that you feel a heavier breeze on your legs, back or face that wasn’t there before.

The literature that I have read and found to be true over the years is that the mirage you see is an indication of everything between the scope and the point that scope is adjusted to. That said I always set my spotting scope to focus clearly on the mirage set just behind the target. I usually set the scope up to get the best clarity of the large target numbers behind the frames and then I will wind the focus in the direction that makes the target clearer though I’ll set it where the mirage lines are concise along a number of target frames. For this reason you need a reasonable field of view but not too large that the mirage lines become too faint.
I find that at the short and mid ranges, 20X is the most magnification needed but at the longs I’ll zoom in a little to get 3 or 4 target frames in view.
Mirage is easier to see clearly and the waves appear thicker and slower at lower wind velocities. When the wind velocity increases the mirage thins out and can be difficult to pick up. The reason that I always have my spotting scope out regardless of conditions or light levels is that the lack of obvious information is just as important as the abundance of obvious information.
The most obvious spotting scope scenario is that you may shooting off mirage in lighter conditions and then all of a sudden the mirage disappears and the flags don’t look too different. Pretty easy to understand that if you take that shot it won’t be consistent. The opposite goes too. If you’re shooting in heavy wind conditions and the mirage is too fast to be usable or you can’t see it and then all of a sudden it appears but again the flags don’t look too far different, you know something different is going to happen to your shot.
An example of a situation that you want a spotting scope and might not realise beforehand is when shooting on the left hand targets and tree line at Belmont. Both shorts and longs. It’s typical to get a strong left wind that you might think is obvious enough just to shoot off flags. I’ve been in this situation countless times with my spotting scope setup and found that the mirage is actually indicating a light right breeze. Sometimes the mirage in that situation is very turbulent, flicks left to right or boils and leans over lightly before it starts to run. But commonly in that situation the mirage does not agree with the flags and the mirage has ALWAYS been right for me.

If you don’t have your spotting scope out, you can’t use it in an unforeseen moment that might benefit you. If the spotting scope is always set up as habit, it will always be there to aid you if needed in conditions that you might not have thought would warrant a spotting scope.

3rd. The rifle scope picture is obviously primarily for aiming but also to quickly identify a picture difference or change which is important in a good F-Class spotting scope system.
I personally don’t believe in setting a rifle scope up for mirage clarity or adjusting the magnification on the mound between mirage clarity and parallax free.
Setup properly, the rifle scope is set to parallax free so that there’s no optical error in sighting. If it’s not 100% set to parallax free there’s no point even worrying about mirage from a spotting scope as your bullet won’t be going where you think you’re aiming. When a rifle scope is setup properly to parallax free the mirage picture is NEVER at its optimal and interestingly the picture is not necessarily at its clearest. This is the key reason for having a second scope setup specifically for mirage.
On high power scope settings the scope picture is rarely clear unless you have a perfect day that’s a little overcast. A lot of people think that’s a disadvantage but it’s not at all. A scope picture can vary in so many different ways due to different conditions and that picture that you get for your sighter is a unique indicator to the condition you’ve chosen to shoot in. If that picture varies, the condition has too and you cannot be as confident that your shot will be consistent with the last.
Once the flags are right, the spotting scope mirage is right and you’ve remembered your rifle scope picture and taken your first sighter (first reference shot), you now base every other shot off that one.

You might confirm flags and spotting scope then go to the rifle scope and find that the pictures darker or brighter, STOP and wait or be prepared that you may have a high or low shot. This will give you vertical dispersion due to optical error. Remember the old saying, “light up sight up, light down sight down”. When the picture darkens you can easily have shots 1/2MOA high plus. Wait for the same light level as your sighter. Wait until you feel that your eye has stopped adjusting. For me that’s normally at least few seconds after a light level change, I’ll normally count out around 8 seconds. This happens more frequently than most shooters realise because of patchy clouds casting running shade that traverse up, down and across the range.

You might go from your spotting scope to the rifle scope and find that although the rifle scope is not adjusted for mirage clarity, the picture looks different to what it did for the sighter. Often it’s not easy to quickly describe how it’s different but you can just tell that it’s not the same. It may be blurrier, it may be clearer!, the rings might become crystal clear and contrast more obvious where it wasn’t before, you may actually be able to see mirage lines where you couldn’t in the sighter or visa versa. The key is, if the scope picture is different, stop and wait until it is the same as something that you’ve proven in your sighters (reference shots) or even learnt in a bad shot.



I have my spotting scopes anchor point on my rear bag plate. That way the scope is always in exactly the right position for my eye.
I prefer straight spotting scopes. I use it with two eyes open and when you get the knack of it, being able to watch flags and mirage at the same time gives you very useful information quickly.

When you regularly use a spotting scope your eye is trained to pick-up and see mirage more easily. I find that when I’ve had weeks on end away from shooting I come back and my eye doesn’t see the mirage as easily especially in poor mirage conditions until it is retrained. That’s seems to take a a few shoots.

When you start using a spotting scope, it’s easy to succumb to the “added hassle” and give it away. My advice is to push through the learning curve and be persistent. It will pay dividends.

Using a spotting scope in F-Class is not about ONLY going off the spotting scope. It’s important to realise that its most effective when used as part of a system. Flags, spotting scope, rifle scope. An important point to make on the system is on what to do after the shot is gone. This is where you learn some of the best lessons. As soon as the shot is gone, train yourself to quickly lift your eyes to recheck the flags and then fluently and quickly re-check the mirage through the spotting scope. Mirage changes quickly and you need to check that what you just shot in is the same that you intended to shoot in. Check the target monitor last, well and truly last, AFTER you understand the intended condition and actual condition.

Edit: added pic, courtesy JenniH.

[Rich4]

Well written, awesome material, thank you

[Mozzie]

Denis A
Wow, a very detailed response, explaining exactly the info that's required to tame the mirage and use to an advantage for repeatability.!!!
Thank you

[GSells]

Well said Dennis , I will also back up what Dennis said . That once you go down this path , always setup the spotting scope and stick with it ! Sometimes you will fail badly and learn . Other times you will win ranges when others struggled . Like I said , I’m nearly 3 years in and still learning .