Rifle Scopes Scope image fringing

[Valken]

I have a scope that cause the image to fringe. Another words when I have a target of high contrast IE: black print on a white back ground there appears red on the top and tips of the black print. What causes that? Is this something that should be excepted? Any remedies? How should I address it with the scope manufacture? It also seems to have a soft image when looking at high contrast targets. Any help would be appreciated

 

[The Mechanic]

Re: Scope image fringing

What scope is that? sounds like a poor job in the lens coating.

 

[hunter223]

Re: Scope image fringing

It isnt to be expected with high-end glass

 

[CanPopper]

Re: Scope image fringing

That's due to the objective of the scope being an achromat. Rifle scopes are of a refractor type design. Light enters your scopes objective and then gets bent toward the eyepiece.

However, light is made up of different colors. In a cheaper scope design (called achromatic), the different colors separate as the light is being bent towards your eyepiece. So when you see the image, you will notice color fringing especially in the areas between dark and bright.

Higher end scopes use more expensive lenses like ED elements or more lenses like in a triplet design (3 front lens) which bend all the colors uniformly so they don't separate out.

Two remedies if you keep the scope:
1. Screw a color filter onto your eyepiece to filter out the separated colors.
2. Run the scope at lower magnifications so the separated out colors are not as noticable.

 

[Black Majik]

Re: Scope image fringing

Meh, I even get a bit of chromatic aberration shooting the white side of a USPSA target against black shoot n' sees on my NXS 5.5-22x.

It gets annoying, so I switched the target around to the brown side.

 

[Valken]

Re: Scope image fringing

Has anyone else had the same experience with there high end scopes fringing, IE; S&B, USO, Nightforce. I see one NSX has the same issue. Are there more. Is is a safe bet that the these "high end scopes" are what CanPopper called achromatic lenses and that is what you get? The scope I am referring to is one of these high end scopes by the way.

 

[CanPopper]

Re: Scope image fringing

My Zeiss Diavari fringes a bit at the highest magnification (24x) if my head position is incorrect. Back it down to 20x and below and no color fringing whatsoever.

No fringing on my Leupy Varix-III but it only goes up to 20x.

When talking about fringing, you should also state at what magnification does it become visible. If a scope doesn't go to very high magnifications (defined by me as 15x or greater), even cheaper scopes should not have an issue.

 

[Valken]

Re: Scope image fringing

The max power on the scope is 10x and it is very noticeable at around 8x and up.

 

[CanPopper]

Re: Scope image fringing

If it starts fringing at 8x and up, that is one super crappy scope.

Even my Mueller TacI at max (16x) and my Mueller TacII at max (10x), do not fringe. And my Muellers only cost me around $200+.

 

[Valken]

Re: Scope image fringing

Man this is not suppose to be a crappy scope and I paid more than $200 for sure. shit I hate it when problems pop up like this. You spend the money so you don't have the problems

 

[RemingtonSPS]

Re: Scope image fringing

You seem like your hesitating to say who makes the scope. Its good to know of potential problems from a manufacturer. Your choice.

 

[Rob01]

Re: Scope image fringing

Did you focus the reticle prior to using the scope?

If not go here
http://www.nightforceoptics.com/LIBRARY/NFOwnersManual5_08_webNoWarrantyCard.pdf

And look at Page 4 for instructions. They are NF specific but the method can be used on any scope.

 

[BOLTRIPPER]

Re: Scope image fringing

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rob01</div><div class="ubbcode-body">Did you focus the reticle prior to using the scope?</div></div>



in my best homer simpson...."DOAH !"

 

[Valken]

Re: Scope image fringing

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Did you focus the reticle prior to using the scope?</div></div>
Robo, good question. I have more than a few scopes so while I am not an expert I am a bit comfortable with the adjustment with the scope. The Ret is clear and sharp. Down in the lower power range there are no apparitions (at least not that I can see). It's only when I go up in power that I see it. I didn't notice it until I went out and zeroed the scope. I paid little mind to it at that time, since my focus was to zero the scope. It was not until I got the target out at distance did it become annoying.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">You seem like your hesitating to say who makes the scope. Its good to know of potential problems from a manufacturer. Your choice.</div></div>

I don't know if that's the right choice right now. I wanted to determine if this unusual first, what causes it and what if any is the fix for it. I paid $2000 for the scope and cheap glass is not want I wanted to hear (If that's the problem). If not I would hate to be the one who labels someone. If so then I have no problem saying who

 

[CanPopper]

Re: Scope image fringing

All $2K scopes should come with apochromatic front objectives. Sounds to me like you may have a QC issue.

Most scope front objectives use either two lenses or three lenses. If the lenses aren't positioned correctly when the scope is made, then the different colors of light don't get bent together properly causing chromatic aberration (CA).

It is nuts to hear about CA at 8x. Even my $30 Wally World pellet gun scopes don't do that. Send it back to the manufacturer for warranty service.