Rifle Scopes Does CA really matter?

Ouch. My head hurts. Without speaking all technically and as a regular Bushnell user, I’d say the scope I have (ERS) is useless beyond 1k. Ran out of parallax and targets were extremely difficult to see.
 
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Depends how much you'd find it distracting in your image and how far off center of the scope you are when taking a shot. Will it cause you to miss a shot and lose points? Nope. Almost all scopes have some CA, some more than others. If you don't care about some purple fringe along the edges of some objects in your view but the scope tracks true it won't have any effect on your shots.
 
It is just annoying. And personally, if I'm paying any significant amount of money for an optic, it needs to have quality engineering behind it, otherwise WTF am I paying for. While CA alone doesn't really affect my shooting all that much (unless it starts to obscure/blur the target at really long distances, which can happen), it can contribute to eye fatigue in some small part. BUT... look, CA is by definition an error. It's a defect in the optical system. It's the inability for the optical system to focus all parts of the image at a single point in space (your eye). Whether that bothers you is a different story.

Any optic over $2800, let alone $3,000+ should have the least amount of CA possible IMO. This is 2018, not 1975. Optics have come a long way. And the prices have too. So I expect high engineering to go along with the high prices. If you're getting a lower-end optic, maybe CA isn't so much a concern for that type of consumer. Gotta pick and choose what's important to you, as always.
 
FourT and Bill pretty much summed up my thoughts. It's an annoyance to me and large enough that depending on what i'm paying if it's prevalent i'll get rid of the optic or send it back.

Not to deter you from your scope purchase but my HDMR II showed significant CA, along with sub par edge to edge clarity. My cousin's DMR II is much of the same, not as hazy around the edges of the image but it was certainly there and again still had CA.

On another note i've been looking at the PST Gen II i just picked up for a bit now and am whole heartedly impressed for the money. I haven't put it in a scenario where i could tell if it was going to exhibit CA and haven't tested it at low light, but the resolution and color accuracy is impressing me. Reminds me a lot of the LRHS, possibly with better edge to edge clarity.

FWIW my HDMR II was great during low light, which was something that hindered the ERS forever. I thought the resolution was solid step up as well. But this is a sample of 2, i don't think two scopes are necessarily indicative of the entire lineup. If there is one thing you can be certain of with Bushnell it's that their mechanics work. Flat out i've never seen on that wouldn't track and have never had one that wouldn't track. Something that can't be said for both the PST Gen I and II.
 
Another thought:

Let's say you're considering two scopes that, on paper, are identical in their features and specs and price-point. The only difference? One has more CA than the other. Which would you choose? It's an easy answer. You'd choose the one with less CA. At least a reasonable person would. So that should tell you something.

Whether or not a scope has CA, and to what extent, might not be the #1 deciding factor to someone when scope shopping. But it is one box that gets checked when many people look around. Gotta take all the other things into consideration as well. But I know there are a few other scopes out there that came close for me, but because they had a lot of CA, I went with something else since all the other specs were fairly close.
 
FourT summed it up nicely, this is 2018 not 1975, so when you pay top dollar for anything with lenses you expect it to be "the best" and that includes being able to use the proper glass and align them properly to reduce CA (remember there is no optic in existence (that I know of) that uses multiple lens elements and has no CA whatsoever, but there are methods in manufacturing that can help minimize CA). I understand there are those who complain about those of us who complain about CA; they don't see it in their scopes and don't understand what the big fuss is all about, and as I've said before, if you're a shooter who hasn't noticed CA in your scope, then don't go looking for it, plain and simple.

I have come to accept this level of CA for this price point, the DMR II, XTR II, PST II all exhibit about the same level of CA from the scopes I've had personally. The $2k price point would be the next step up, the new Leupold Mark 5HD sounds like it might be really good whereas the Steiner T5Xi has too much CA for a scope at this price point IMO. Next up would be the $2500 class which the Vortex Gen II and AMG fall into, and maybe if you get a good sale on a PM II 5-25 or Kahles K624i. Within this range the AMG easily takes the prize, I have seen few scopes that can better the AMG in control of CA, including a 3-20 Schmidt and 5-20 Schmidt that I've had. The Kahles is the worst of the bunch in the $2500 - $3k class, something I'm hoping the new K525i will rectify. Other than the Kahles (and I've heard the Steiner M5Xi might have some CA issues as well - more than the norm for the price range), the $3k class is pretty solid, the Schmidt's, the Nightforce ATACR F1 5-25, the March and the Minox ZP5 - having the best control I've seen of CA (TT525P is supposed to have superb control of CA as well). Some new players this year are the ZCO ZC420 and ZC527, the Kahles K525i and K318i, the Steiner M7Xi 4-28 and the Leupold Mark 5HD's should hopefully prove to improve upon previous scopes, already the Leupold Mark 5 is getting some pretty promising reviews for its price point.

Below is a shot I took through my DMR II which shows some of what the CA looks like, keeping in mind this is exacerbated by the fact that the CA from my camera/lens combo compounds the CA through the scope, to the naked eye, the CA exists but is not as pronounced.

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wjm308, I'd add the Athlon Cronus BTR 4.5-29x56 to your list of scopes under $2k that do a very respectable job of handling CA. Been impressed with the two I've handled extensively.

I had to send back my XTR II 5-25x50 twice for CA and other issues. Eventually sold it when they replaced it! Just could not make myself look past the CA.
 
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So you're saying if we used the scopes in outer space we wouldn't see any CA? I bet we'd have much higher BC's out there too :D Seriously though, are you inferring a true vacuum environment (no air) or are you speaking metaphorically?

Metaphorically. Visible CA is a symptom of how the system is built and it can have other repercussions.

ILya
 
There are lots of things that the scope Nazis on this forum complain about that don't matter when it comes to actually hitting a target:
1. Mushy turrets
2. CA
3. 2/10 hashes on a reticle

These things get mentioned in every other post it seems like. I don't want any of those things in an expensive scope, but they are discussed endlessly on this forum.

In if a scope tracks true I can hit targets with it period. CA means nothing to me.
 
There are lots of things that the scope Nazis on this forum complain about that don't matter when it comes to actually hitting a target:
1. Mushy turrets
2. CA
3. 2/10 hashes on a reticle

These things get mentioned in every other post it seems like. I don't want any of those things in an expensive scope, but they are discussed endlessly on this forum.

In if a scope tracks true I can hit targets with it period. CA means nothing to me.
Since I tend to bring up CA in my scope reviews and on other posts within the forum I assume you are referring to me as one of your "scope Nazis". You might want to think about using a different term when referring to folks who might be a bit more detail oriented than you, I've been called a lot of things but a "Nazi" infers a lot more than just being detail oriented. Since this is a post about whether or not CA even matters I think its fair that we have different points of view represented and I respect your point of view represented above, but calling out some contributors as Nazi's is a bit over the top.
 
Metaphorically. Visible CA is a symptom of how the system is built and it can have other repercussions.

ILya
Thank you ILya, I wasn't sure if there was some optical characteristic you were inferring when you mentioned vacuum. In regard to the "other repercussions" with scopes that suffer from heavy CA are you referring to the scotopic vision that occurs within the transition to low light? I'd be curious to hear more in this area as I don't know much about this side of optical engineering.
 
Since I tend to bring up CA in my scope reviews and on other posts within the forum I assume you are referring to me as one of your "scope Nazis". You might want to think about using a different term when referring to folks who might be a bit more detail oriented than you, I've been called a lot of things but a "Nazi" infers a lot more than just being detail oriented. Since this is a post about whether or not CA even matters I think its fair that we have different points of view represented and I respect your point of view represented above, but calling out some contributors as Nazi's is a bit over the top.

Get over it.
 
wjm308, I think you, as well as the rest of us called "Nazis," need to cut Mordamer some slack!

If nothing else, Mordamer is honest and transparent! Have a look at the tag line under his screen name. He freely admits he is a "Professional Know It All," and, it appears the moniker fits him well!

:) Mordamer, just kidding you man! Hopefully you have a sense of humor and can take it as well as you dish it out. And if not... oh well, you'll just have to get over it! :eek:(y):)
 
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All's good guy!

Everyone's eyes see things differently and what may bother one immensely may not be noticed by another. Your perfect scope may be offensive to my eyes, as well as the other way around. It is wonderful to have choices.

;) :) That way the "know it alls" and the "snowflakes" can co-exist in the same happy space! :) :cool:
 
Human eyes are sensitive to certain things, and insensitive to some others. Also our eyes are adaptive for certain things, after you stare through scope for some time.

In a scope world, the optical clarity, resolution, the "reflection of reality", are actually not sensitive to our eyes, you have to look side by side to tell, if the difference is not major, like between K624i and SuB 5-25.

But our eyes are always sensitive to high contrast color, like purple or blue CA edges. CA was caused by many reasons, the color itself is not a problem, but it is an indicator, about how well the scope was designed and built optically, how much coaxial tolerance error is allowed when aligning the glasses in the tube. So it is fair to use CA to determine the scope optical performance because that is something our eyes can easily see. I personally have always found it to be true, the scope that has less CA, has better optical performance from all other perspectives like clarity and resolution, once measured with mechanical approach.

For certain type of shooting like PRS, the accuracy requirement is actually not very high. Human and nature factors are major. In that game, CA does not matter much, neither is the scope's optical performance if not too horrible. Mechanical performance is more critical to the success.

CA is not just a color change, that's what I have learned.
 
It’s a fuggin gun sight. CA should bother you if you are photographer for National Geographic.

This ranks right up there with Ghilli Suits and Freaking out over a scratch on a new ATACR.

I wish Vjj Punisher would make a meme about “CA”....
 
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I had a T5xi 3-15 as well as a Burris xtr 2. I have since sold both but I noticed CA more in the T5 than the XTR 2. The T5 hands down had better glass. Good color transmission but it had more CA. I didn’t understand it but it was there. Both scopes tracked true and I would take either of them to a match or on a hunt without hesitation. I never missed a shot due to CA. I was slightly annoyed by the T5 at times though. Turrets were excellent. The mark 5 is fantastic in comparison to the T5xi in the CA department. Glass is very good in the Mark 5.
 
It’s a fuggin gun sight. CA should bother you if you are photographer for National Geographic.

This ranks right up there with Ghilli Suits and Freaking out over a scratch on a new ATACR.

I wish Vjj Punisher would make a meme about “CA”....

Your not posed to scratch’m........how you supposed to know if their worth a shit??? That whole National Geograpic and color thing is just racist.....brute!??
 
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Even if it doesn't make or break whether someone hits their target, it does for me. Which one of these would you rather stare at for an hour? The scope is the interface you have with your rifle. Just looking at the bottom image here makes my eyes hurt. CA definitely affects whether or not I make my shot. It's distracting. It's annoying. And it actually does cause my eyes to fatigue after a while. It makes the image appear blurry due to the non-convergence of color, even when the image is focused. And that causes my eye to constantly attempt to focus on something that can't be focused. If you don't give a shit about CA, awesome. You're lucky. Bothers the fuck out of me, though.

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It’s a fuggin gun sight. CA should bother you if you are photographer for National Geographic.

This ranks right up there with Ghilli Suits and Freaking out over a scratch on a new ATACR.

I wish Vjj Punisher would make a meme about “CA”....

Haven't seen VJJ in some time, though his avatar of Gollum holding a Schmidt or some prized scope like the ring itself would have me believe he might not agree, though less that in and of itself was a meme.

I don't own a ghillie nor even understand the reference but if that thing is $3000 and has shades of purple in it you can bet i'd be displeased lol
 
I run high end optics so CA has never been terribly noticeable, but the only time I've actually noticed it is when I'm actually examining an optic and looking for it.

My scopes aren't for fingering a drooling over, I shoot with them. When I'm actually shooting them I've never noticed it.

I think it's silly that some people go full retard over it and it tells me just how much time they spend playing with their optics than shooting them. Again though, I've never had one where it was "bad".
 
I have a DMR2, and have noticed that the CA really becomes apparent once you reach 20-21x magnification. I usually just stay away from that end of the magnification range and limit it to around 18x, where I find the image to be much clearer from edge to edge, and with far less CA.
 
Before I got started down this path a Viper G1 and Mark 5 was good eneough.......bastards!? Now it’s SHV F1 and ATACR F1. I agree that if your going to spend your money you should get what you want. That said, you shouldn’t expect a donkey to win the Kentucky Derby?
 
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Excerpt from CA Pew Pew Match Booklet
Stage #7 Birds of a Feather

Target D1 a 300% Red Cheeked Cordon Blue Finch at 447 yards engaged by three rounds followed by Target F2 a 150% Red Eared Black Rump Waxbill at 553 yards engaged by 3 rounds, then mag change, then Target D3 a Lady Goulian Finch at engaged at 668 yds with 3 rounds. Shooters rifle must touch the birdhouse barricade for all shots.

Minus 1 point per hit on similarly co located woodpecker, barn owl, and crow targets.
 
Looking at those images Fourt6and2 posted I can honestly say I have never seen any high end scope exhibit that degree of difference in image quality!
I have the Kahles (which some say has bad CA) and the TT (which most say is the holy grail of optical quality) and the difference in image quality (?CA) is so small I am seriously thinking about selling the TT. In a lot of shooting conditions there is no difference in images.
Agree with others, its a sight. For me, as long as the image doesn't affect my ability to hit target I'm good.
 
Get over it.
Why don't you tell the Jews, the Poles or the numerous other people groups who suffered at the hands of the Nazi's to "get over it", that is in essence what you are saying. Maybe you're a someone who has no real idea of who the Nazi's were or maybe you're one who denies the Holocaust, either way, the Nazi's were a brutal and barbaric regime that committed horrific atrocities against the human race with the murder of over 6 million innocent people, this is why I take offense to your terminology, have some respect for the people who suffered through their regime and don't use the word flippantly to identify someone who does not agree with you.

I apologize to the OP for getting off topic here.
 
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Looking at those images Fourt6and2 posted I can honestly say I have never seen any high end scope exhibit that degree of difference in image quality!
I have the Kahles (which some say has bad CA) and the TT (which most say is the holy grail of optical quality) and the difference in image quality (?CA) is so small I am seriously thinking about selling the TT. In a lot of shooting conditions there is no difference in images.
Agree with others, its a sight. For me, as long as the image doesn't affect my ability to hit target I'm good.

I'm just thankful there's competition in the marketplace so we all have plenty of options at our fingertips. If all the naysayers and grundle trolls had their way, we'd only have 2 scopes to choose from and there would never be any innovation or improvements in technology. Who needs tool-less zero? Never invented. Who needs locking diopters? Never invented. Who needs a 7-35x scope? Never invented. Who needs less CA? Higher manufacturing standards/tolerances never sought out. Who needs zero stop? Never invented. Who needs satisfying turret/click feel? Mushy turrets are just fine. None of these things really "make or break" whether you hit your target to be honest. So hey, throw 'em out the window. Reticles? Don't even get me started. A simple Mil-Dot from 1970 is all you need. ;) Hell, who needs custom actions like a Defiance or ARC or Bighorn? Throw a good barrel on an off-the-shelf 700 and sign up for PRS. Not like that integrated bolt handle or bolt fluting is gonna make or break your shot. Custom molded-in colors from McMillan stocks? Fuuuuuuck that. Nothing to do with hitting the target.

Basically all I'm saying is when manufacturers try to make their products better (like reducing CA), even if it's a small improvement, we all benefit in one way or another. To sit back and go, "I don't like it. It doesn't make or break my shot. It's splitting hairs. Who cares?" is lazy thinking and hinders progress.

I'm not calling you out on these things, nfoley. But yes, the difference in CA between a TT and Kahles is relatively small when you compare a gun-counter-specal $300 scope to the TT. But when you have $3-4K in your pocket and two scopes in front of you to choose from, that's where all these small differences matter. The '10 Viper ACR laps the Nurburgring in 7:12.13. The Porsche GT3 did it in 7.12.7. Does 0.57 seconds REALLY matter? Fuck no. But people still agonize over it.
 
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I'm just thankful there's competition in the marketplace so we all have plenty of options at our fingertips. If all the naysayers and grundle trolls had their way, we'd only have 2 scopes to choose from and there would never be any innovation or improvements in technology. Who needs tool-less zero? Never invented. Who needs locking diopters? Never invented. Who needs a 7-35x scope? Never invented. Who needs less CA? Higher manufacturing standards/tolerances never sought out. Who needs zero stop? Never invented. Who needs satisfying turret/click feel? Mushy turrets are just fine. None of these things really "make or break" whether you hit your target to be honest. So hey, throw 'em out the window. Reticles? Don't even get me started. A simple Mil-Dot from 1970 is all you need. ;) Hell, who needs custom actions like a Defiance or ARC or Bighorn? Throw a good barrel on an off-the-shelf 700 and sign up for PRS. Not like that integrated bolt handle or bolt fluting is gonna make or break your shot. Custom molded-in colors from McMillan stocks? Fuuuuuuck that. Nothing to do with hitting the target.

Basically all I'm saying is when manufacturers try to make their products better (like reducing CA), even if it's a small improvement, we all benefit in one way or another. To sit back and go, "I don't like it. It doesn't make or break my shot. It's splitting hairs. Who cares?" is lazy thinking and hinders progress.

I'm not calling you out on these things, nfoley. But yes, the difference in CA between a TT and Kahles is relatively small when you compare a gun-counter-specal $300 scope to the TT. But when you have $3-4K in your pocket and two scopes in front of you to choose from, that's where all these small differences matter. The '10 Viper ACR laps the Nurburgring in 7:12.13. The Porsche GT3 did it in 7.12.7. Does 0.57 seconds REALLY matter? Fuck no. But people still agonize over it.
Of course lots of options are good. Not sure where you got that anyone said there should be only limited options with scopes? All I read are different personal opinions about different scopes.
 
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Of course lots of options are good. Not sure where you got that anyone said there should be only limited options with scopes? All I read are different personal opinions about different scopes.
Because that’s the point of contention around CA. That because it doesn’t affect your ability to hit the target it doesn’t warrant criticism as to whether it’s there or not. Which the same could be said about all the things FourT listed.

As to reading personal opinions of scopes, that’s the very nature of optics and how they're perceived person to person. Outside of some expensive equipment to test the IQ of optics you’re left with personal opinions which will vary.
 
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