Does Objective Size Make A Difference Reading Wind Mirage

[SeboCreek]

Looking to upgrade my spotting scope to help read wind mirage. Does a 95mm objective provide better wind mirage than an 85mm? I guess wondering because of attachments to rifle scopes reducing the objective that they say helps read wind. Thanks for any help/opinion on this.

 

[Grumpah]

In my experience EVERYTHING is dependent on the quality of glass. I have had much better successes with a smaller diameter quality lens than a larger diameter lens of less quality. Lens coatings also seem to come into play. Generally speaking, I don't think there is a definitve answer to your question. In the case of rifle scopes, the thought that a 50mm + objective lens gathers more light than a 44mm or 40mm objective lens is simply a myth. Anything larger than a 44mm is only marketing fodder. Same with scope tube size. All a larger scope tube does is give you more OA adjustment and has nothing to do with gathering light. I assume lens sizes apply for spotting scopes as well. It's all about the quality of glass and lens coatings. Of course, this is just my humble opinion.

 

[waveslayer]

I don't think so, it's more of a light transmission for spotting scopes. I have never noticed a superior optic with different mirage clarity. It's easy to see, but again I'm using mostly nice glass. But the low light conditions are very dependent on optic and objective lens sizing

 

[Grumpah]

I defer to your experience as I've not had the issue. Thank you, I'll keep that in mind to eveluate next time out. Of course, my eyes are old...I may just not be seeing what you are. Best of luck.

 

[SeboCreek]

Was looking at the BTX 85mm vs the BTX 95mm. Have an old Swarovski STS (I told you it was old) with fixed 30 power Swarovski eyepiece. Will probably be matching whatever I buy with ATX eyepiece. Appreciate the input.

 

[SeboCreek]

Any other thoughts?

 

[Grumpah]

I will hit the range I belong to this week, possibly even later today. They have a number of different power spotting scopes to use. Just for fun, I am going to try and verify the mirage scenario. No promises from my end, as I previously stated my eyes aren't what they used to be...lol, Ah to be young again....I will report back. As you brought up an interesting subject, I'd like to verify so I can validly whine to my Ophthamologist!
LMAO!

 

[waveslayer]

Was looking at the BTX 85mm vs the BTX 95mm. Have an old Swarovski STS (I told you it was old) with fixed 30 power Swarovski eyepiece. Will probably be matching whatever I buy with ATX eyepiece. Appreciate the input.

I have both... I prefer the 85 for hiking around because of the size differences. The 95 is a big spotter and you throw in the BTX it's even bigger. That's why the NF spotter would be interesting to try out.

The 85 does everything, the 95 can do, but at lower light you get a tad, so they say, better lighting. I can't tell the difference.

If you don't plan on hiking with it, or have horses to take you way back, I'd give the 85 a hard look. But I do love the 95

 

[lancetkenyon]

BTX w. 85mm is 30X magnification
BTX w. 95mm is 35X magnification

I don't think 5X is going to make a huge difference in reading mirage/wind.

I think glass quality/clarity/resolution is much more important for reading mirage and wind. The ability to focus at varying distances helps give you a more accurate reading of what wind is doing from shooter to target. Because wind is anything but constant in any type of terrain change.

Also, being able to determine wind DIRECTION is important. Then determining what you are seeing as far as deflection will help you decide on wind SPEED. But you have to see these changes in real time. Panning to find where mirage appears to be blowing either directly at or away from you (mirage not blowing left or right) will help determine the direction along the shot line. Once you find where mirage appears to be straight up, you will know by feel (either on your face or back) which way it is blowing at the shooter, and you can determine from there the clock direction.

Remember too, there are varying wind values at clock positions (these are the easy versions to remember).
12:00 or 6:00 still effect bullet impact (high or low), but not drift (not including spin drift).
12:30, 5:30, 6:30, and 11:30 are a 25% value of wind speed.
1:00, 5:00, 7:00, and 11:00 are a 50% value of wind speed
1:30, 4:30, 7:30, and 10:30 are a 75% value of wind speed
2:00, 4:00, 8:00, 10:00 are a 90% value of wind speed
2:30-3:30 and 8:30-9:30 are a full value wind

Getting good at reading wind takes practice, and actually shooting in the wind. If you have buddies you shoot with that have the right equipment and experience, it helps flatten the learning curve greatly. They can help explain what they are seeing, and why they are making the wind calls they do. This is a typical shooting session with a couple of my shooting buddies. Lots of $ in glass, amd this isn't even close to all of it.

 

[SeboCreek]

Thanks so much for your comments. I did take courses at Barbour Creek and learned a lot. I just need the proper equipment to help with practicing and seeing the mirage better. It appears you and your shooting friends are ready. Again, thanks for you input.

Great attachments.

 

[waveslayer]

The best way to see mirage is Parallax adjustment, if you do not have it you can't see it...

 

[Grumpah]

Well Sebo, here's my range report. Bear in mind, I belong to a small private membership only club and the furthest firing range is 400 yards. The outcome, however, was interesting to me. I'll start by saying that previously to today, I had always checked out the 85mm spotting scope.

Today, I checked out a Vortex Diamondback HD 16-48x65mm and a Vortex Viper HD 20-60x85mm (my usual). It was very interesting to me to find that I could actually "see" the wind mirage with the Diamondback (the lesser powered scope) and not so much with the more powerful Viper. Bear in mind I'm well over 21 years old...lol...have myopia and astigmatism.

The Viper was better, for me, to see bullet holes at 400 yards but not so much the wind mirage. Hence, I really never noticed in the past as I pretty much gaged my shots watching the wind flag or vegetation. Where I hunt here in Central, TX my shots never exceed 400 yards. 90% are within 200. Thanks so much for bringing up the subject. I learned something today!

 

[Baker Alvin]

Tagging IN

 

[SeboCreek]

Thanks for the feedback. I am well north of 70 so my earsight not quite what it used to be. I hunt in the hill country and usually anything over 200 unusual. I have placed a few full sized relative targets on the property and can stretch out to 800 plus. That is what I am planning on. Just got the bug after going to the shooting school. Appreciate the input.