rolling Ball effect???

Titan34

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I am now leaning towards some used swaro el 8.5x 42 or SLC 8x42... The more I research the more I want good glass. I mainly hunt whitetail deer in michigan and ohio. Can anyone comment on the rolling ball effect. id like to get the best bang for my buck but I do not want this so called effect.
 

Xlr8n

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Some folks see it when panning, some don't. The flat field of the EL's would produce it where the traditional view of the SLC's would not. Both are fantastic glass. I'd recommend you go to a shop and try the EL's to see if they give you any issues.
 

JLane330

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My understanding is that some people are sensitive to this, and some aren't. Not sure if it's dependent on the optics, the person, or both.
I have SLC's (10x42) and see ZERO rolling ball effect in them. Great glass! When I tried using my buddies Vortex Vipers, they had it bad and gave me a near instant headache. I do not see it with Leupold BX-4's nor some Leica's. Can't recall seeing it in some EL's, but I used them very little just to play with the rangefinder on another buddies.
Best to check them out in person if you can.
 

mainbeam pursuit2

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I have two pairs of the SLC's never any problems. Before I bought the last pair in 2016, I tried the EL's got the rolling ball effect bad. Have heard that it's only in the field flattened lenses set up. Haven't heard much being said about it anymore, maybe they have found and corrected the cause. I have the NL's now and not having any rolling ball effect.
 

DavePwns

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Its all personal preference, I had to sell my SLCs because my eyes didn't like the lense and actually got dizzy after 20 minutes of glassing on a tripod, I got the ELs with the flat field view and absolutely love it. I can't tell you how many hours I've looked through them and never had any problem whatsoever. I don't think I'll ever need to buy new glass again.
 

PHo

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It’s very important that you try the ELs for yourself to see if you are affected by the rolling ball effect (SLCs don’t have this effect because they don’t have the field flattening lenses). If you are not affected by it then I would recommend going with the ELs, I do think the optical quality is worth the difference in price over the SLCs. However if you’re like me and are in fact affected by rolling ball, then the SLCs are still top of the line IMO. But you have to see for yourself.
 

Q child

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If you do not want the rolling ball effect then get the SLCs. As others have described its a type of distortion that is associated with the flattened field of the ELs.
Can you see the rolling ball? And if so, does it make you sick?
Or, are you saying you have heard of this phenomenon, and want to avoid it because you have heard it makes other people sick?
I can see the rolling ball in the ELs, but it does not make me sick. The ELs are excellent. Still, I think I prefer the SLCs because they are a little more compact, have a better tripod mount, and are maybe a little brighter.
 
OP
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Titan34

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If you do not want the rolling ball effect then get the SLCs. As others have described its a type of distortion that is associated with the flattened field of the ELs.
Can you see the rolling ball? And if so, does it make you sick?
Or, are you saying you have heard of this phenomenon, and want to avoid it because you have heard it makes other people sick?
I can see the rolling ball in the ELs, but it does not make me sick. The ELs are excellent. Still, I think I prefer the SLCs because they are a little more compact, have a better tripod mount, and are maybe a little brighter.
I have never looked through either set.
 

Q child

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I have never looked through either set.
Sure. It seems that either of them work for most people. As some have chimed in here, they have more specific needs and had to choose one or the other, but I would guess they are unusual in that respect. I don't have any science or anything to back that up, just the feeling that I get from asking people and reading forums.
I know its stressful when your thinking about dropping that kind of cash especially when buying used and there isn't the possibility of returns. But I bet whatever you choose will work for you.
 

ZDR

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I prefer the field flattening lenses in the ELs. The sharp, crisp edge to edge view is excellent and the rolling ball does not affect me at all. I use my EL 8x32 for everything including birding where you might be focused in on a fast flying bird and I don’t even notice the rolling ball. If I ‘look’ for it then I notice it. If you’re holding steady, you can look from edge to edge and everything will be sharp and crisp.
the SLCs are great with a nice center sweet spot, but not the same as the ELs imo.
 

JLane330

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I've only noticed the rolling ball effect on certain optics when scanning areas back and forth. So, even if a set has it, and you can see it, it really depends on how you use the glass. If you're just looking at something stationary or a fixed area, then it's most likely a non-issue.
Something to consider...the resale on Swaro optics seems to be excellent. Might be worth giving them a shot, and if they don't work out for you, reselling should be pretty easy.
I can honestly say that when comparing my SLC's side by side with a buddies EL Ranging 10x42, the images appear to be equally sharp and clear edge to edge. If there is a difference in color and/or clarity, I don't see it. I prefer the ergonomics and size of the SLC's as well as the cost difference.
 

Bkdc

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Every pair of eyes is different. I’ve never encountered it or if it was there, I was not bothered by it. It is apparently most severe on the EL 8x32 and less severe on a 42mm. I’ve also heard reports of people being very bothered by it, not using an EL for a year or two and returning to using the EL and noticing the effect was completely gone.

You have to try it yourself. And even if you try it and seem to be getting along well with your bino, you may notice it weeks later and then be bothered by it.

The Zeiss SF designers tweaked the distortion to minimize this effect after feedback from numerous testers/users.

Different binos for different folks. Members of this forum rave about a certain set of binoculars which I know for a fact exhibits mild coma (comatic aberration) near the optical axis. Peripheral coma is one thing but for 1000 bucks, coma in the center would drive me NUTS. Every set of eyes is different and sensitive to different flaws.
 
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Steve C

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Here is an explanation from an optical engineer on Rolling Ball, aka Globe Effect. http://holgermerlitz.de/globe/distortion.html

The effect is principally found with the flat field designs. This design removes any distortion from the edge of the view. This distortion is often erroneously referred to as a design defect. It is not. It is a design decision necessary in curvature designs. That curvature breaks up potential distortion at the field edge when panning. Magnification magnifies everything, including movement. Without some distortion to break up movement of the edge, the viewer becomes dependent on the amount of distortion correction present in their own eyes to do this. Some eyes are far less capable of this than others. Mine are less capable of doing this. I had to punt on several different SV EL binoculars because the effect was bad enough that all I had was an expensive paperweight. However you won't know if the SV EL gets you or not unless you wring one out for yourself. Quality of your eyesight is not much the point. Even though I'm over 70, I still dialate past 7 mm. I can read two lines below the finest 20/20 line. I do not need glasses, have no cataracts, blind spots, glaucoma, or macular degeneration. So there is really no way to predict beforehand.

However the SLC is highly unlikely to have the issue. It is a curved design and has the same basic glass quality and resolution ability of the EL. That is where I'd likely go.
 
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The ELs are pretty famous for “roller-ball.” This phenom is most common with extremely flat-field binoculars, especially those like Swarovski that are flat right to the extreme edge. Zeiss specifically addressed this in their Victory SF Series - they have a very flat field the drops off right at the very edge of the view. When shopping for my last set of binos in direct comparison between the two and roller-ball was much more noticeable in the ELs vs the SFs. Where a completely Flat-Field really shines is in astronomy, but I’m not crazy about it for hunting. If really concerned about roller-ball — never noticed it in Leicas or the Kowa Genesis. Good luck on your search.
 
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The ELs are pretty famous for “roller-ball.” This phenom is most common with extremely flat-field binoculars, especially those like Swarovski that are flat right to the extreme edge. Zeiss specifically addressed this in their Victory SF Series - they have a very flat field the drops off right at the very edge of the view. When shopping for my last set of binos in direct comparison between the two and roller-ball was much more noticeable in the ELs vs the SFs. Where a completely Flat-Field really shines is in astronomy, but I’m not crazy about it for hunting. If really concerned about roller-ball — never noticed it in Leicas or the Kowa Genesis. Good luck on your search.
As a caveat to that, most people don't notice rolling ball. It'll very likely not be a problem for OP. I was worried about it when I got my ELs sight unseen and it's a non-issue for me.
 

BluMtn

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I have had 12x50 EL's for 5 years now and have never even noticed what they call rolling ball, so for me it is not a problem and I get car sick very easy when I am not driving.
 
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As a caveat to that, most people don't notice rolling ball. It'll very likely not be a problem for OP. I was worried about it when I got my ELs sight unseen and it's a non-issue for me.
Don’t believe it can be claimed “most people don’t notice” roller-ball effect from extreme flat field binoculars. It mostly happens when panning, which many hunters often do. So, if folks are using their glass mostly on a stationary tripod, doing astronomy, or just not doing much glassing for game they might not notice when using binos that way. Or if folks haven’t compared them to other binos for panning. But generally speaking the ELs are pretty famous for it.

Know there is a huge Swarovski fanbase here on Rokslide and they are great optics. I own and enjoy several Swarovski products, but the brand is not perfect. Fans often get very defensive when anyone points our any issues with a Swaro. However, a few years back when I was upgrading my binoculars, the ELs were my lead candidate out of the gate. Compared them to just about every other Alpha and although I’m not severely bothered by it, clearly noticed more roller-ball from the ELs than any other Alpha. So, through direct observation I can say that there was more noticeable roller-ball effect from the ELs. Several shop pros and many others concurred with that assessment. Although it wasn’t a huge issue for me it was still an issue that I didn’t enjoy. Don’t know how bad it would be after hours of glassing but didn’t want to find out. For folks more sensitive than me it would likely be a dealbreaker.
 
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Don’t believe it can be claimed “most people don’t notice” roller-ball effect from extreme flat field binoculars. It mostly happens when panning, which many hunters often do. So, if folks are using their glass mostly on a stationary tripod, doing astronomy, or just not doing much glassing for game they might not notice when using binos that way. Or if folks haven’t compared them to other binos for panning. But generally speaking the ELs are pretty famous for it.

Know there is a huge Swarovski fanbase here on Rokslide and they are great optics. Fans often get very defensive when anyone points our any issues with a Swaro.
They're pretty famous among people who actually notice rolling-ball. If you had to assign a percentage to that, what percent of people do you believe see rolling-ball? That's what I'm getting at, I believe it is a vocal minority otherwise Swarovski would be forced by the market to change their product to correct it. Keep in mind I have Zeiss Victory SF binos too. This isn't coming from being a brand fanboy as you implied.
 
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