IOR SCOPES

[Pdvdh]

The IOR 3-18x42mm second focal plane scope with the 35mm tube is the same. Pretty convenient math. At the 10 power setting the hashes are in mils - 1/2 mil and 1 mil. Turned up to 18 power, the small 1/2 mil hashes are 1" at 100 yds and the large 1 mil hashes are 2" at 100 yds. I have two of these scopes and the large 1 mil hashes are dead on (6") at 300 yds with both scopes. I like the simplicity of 1" and 2" per 100 yds when cranking through the math at the 18 power setting.

My assessment: My IOR scopes are a bit on the heavy side compared to some other conventional hunting scopes, but there's no way around that in a tactical-type scope. Their clarity/resolution is outstanding. I really, really like the IOR retical. They aren't as bright (light gathering) as Zeiss Conquest scopes, but they're pretty decent. If I were going to be hunting at night and in dim light conditions a lot, I would go with Zeiss or another good light gathering scope.

You'll be amazed at the detail you can see with the IORs set at 18X once you get the parallax adjustment properly set.

 

[Jeff In TX]

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Their clarity/resolution is outstanding. I really, really like the IOR retical. They aren't as bright (light gathering) as Zeiss Conquest scopes, but they're pretty decent. If I were going to be hunting at night and in dim light conditions a lot, I would go with Zeiss or another good light gathering scope.

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First, scopes don't gather light, they transmit it, but we know what you were trying to say.

IOR scopes have a tremendous reputation for low light transmission capabilities. Actually most would rate them in the top 5. I agree there optics are superb. You would really be hard pressed to find another scope manufacture that can match there optics for color, clarity, contrast and light transmission for the money.

There is a group buy on Sniper's Hide on special IOR 3-18 X 42mm scope that was designed by the input from the board members. I believe it will have a custom reticle though I don't have details.

 

[royinidaho]

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First, scopes don't gather light, they transmit it, but we know what you were trying to say.

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Jeff,

The whole light transmitting thing has never been adequately explained to me. The confusing part is that when I look with the naked eye things are pretty dim at dusk or so. While through a good scope, especially on low power, things are definitely brighter.

Back in the "old days" everyone including dealers etc. called it 'amplification'.

Maybe its just transmitting/concentrating 44 mm (or objective lens size) of light down to what down to what goes into the eye?

I really don't know.

 

[Jeff In TX]

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First, scopes don't gather light, they transmit it, but we know what you were trying to say.

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Jeff,

The whole light transmitting thing has never been adequately explained to me. The confusing part is that when I look with the naked eye things are pretty dim at dusk or so. While through a good scope, especially on low power, things are definitely brighter.

Back in the "old days" everyone including dealers etc. called it 'amplification'.

Maybe its just transmitting/concentrating 44 mm (or objective lens size) of light down to what down to what goes into the eye?

I really don't know.

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Roy,

Your last statement is far too off. Without geeking out on this here goes.

The term light gathering scopes have been around for a long time. But the reality of the matter is scopes don't gather light. Glass by its nature reflects light, thus preventing all of the light available from entering and exiting the glass. Glass does not gather light, nor does it amplify or regenerate light, though it can bend light. It simply lets light pass through. Optic manufactures work very hard developing coatings for there lenses that will reflect back less of the available light source allowing more of the available light to be transmitted through the lenses. Coatings for optics are often designed to work with certain light spectrums. Rifle scopes coatings are no different.

Quality scope manufactures will coat all of there lenses to maximize light transmissions. They usually state there scopes have multi-coated lenses. There goal is to transmit the maximum available light. Cheaper scope manufactures will only coat the outer lenses thus saving money.

It would be impractical and cost prohibited developing a light amplifier for a rifle scope or binoculars. Not to mention the average sized scope couldn't hold the electronics' necessary for the optical amplifier. Fiber optics transmission lines use optical light amplifiers and regenerators. Optical amplifiers lessen the effects of light dispersion and attenuation. EDFA's (erbium doped fiber amplifiers) are one of the more common amplifiers for optical systems. These amplifiers are also designed for a certain light spectrum.

Hope that helps

 

[Jeff In TX]

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Roy,

Your last statement is far too off. Without geeking out on this here goes.

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I meant to say, "your last statement isn't that far off" The system wouldn't let me edit my quote.

 

[royinidaho]

Jeff,

I hear what you're saying......

Not too geeky either /ubbthreads/images/graemlins/wink.gif

 

[Pdvdh]

Re: IOR SCOPES - light transmission ~ light gathering

I also have read praise regarding the light transmission of IOR scopes but it has always been a 2.5-10x IOR or one of the other IOR 4X power magnification scopes. I've read a lot of forum posts including Snipers Hide, Snipers Paradise, 24 hourcampfire, and many articles, and don't recall a single post or article where anyone has done side by side light transmission comparisons with an IOR 6X power magnification scope. If you're aware of any, I would appreciate your posting the web address so I can take a look. A buddy and I went out one winter evening and compared the following four (4) scopes for light transmission, one being my IOR 3-18x 42mm. We both came to the same consensus, from brightest field of view to dimmest field of view. We did turn all scopes to the same power setting for this comparison.

1st - Zeiss Conquest 4.5-14x44mm - Brightest, no doubt about it.
2nd - Leupold LPS 2.5-10x45mm
3rd - Leupold VX3 2.5-8x32mm - Similar to IOR.
4th - IOR 3-18x42mm - Dimmest (Similar to the Leupold VX3).

If the 6X IORs are about the 5th best in light transmission then my comparison couldn't prove it. But they may rank highly against other equivalent scopes that also magnify over a 6X power range. My suspicion is that to achieve the 6X power range multiplication that additional lenses may be required. Each additional lens would cause additional loss of light to the eye.

With respect to resolution, we both rated these four scopes as follows:

1st - IOR 3-18x42mm - Notably the best
2nd - Zeiss Conquest 4.5-14x44mm - Pretty good - similar to Leupold LPS
3rd - Leupold LPS 2.5-10x45mm
4th - Leupold VX3 2.5-8x36mm

 

[Jon A]

Re: IOR SCOPES - light transmission ~ light gathering

Very interesting. My 4-14X50 IOR beats all I have compared it against in low light (though I haven't compared it side-by-side with a Zeiss). It'll be interesting to see how my 3-18 compares to it when it gets here. I don't expect it to be quite as good in really low light because it's at a disadvantage with only a 42mm objective. But I'm hoping it'll be good enough. /ubbthreads/images/graemlins/wink.gif
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With respect to resolution: 1st - IOR 3-18x42mm - Notably the best

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Now that's what I'm really looking forward to seeing!

 

[Pdvdh]

Re: IOR SCOPES - light transmission ~ light gathering

Thanks for providing that additional information and feedback. Interesting stuff. I understand that light transmission is mostly to do with the quality of the coatings applied to the lenses, given lenses of similar quality.

I don't want anyone to think I don't like the 3-18x42 mm IOR. I like them a lot. That's why I own two of them. I just thought it might be helpful to provide my impressions from the comparison testing we did, since I figured others might also own some of these same scopes. That way they could get an idea of what to expect with the 3-18X IORs.

I agree that with their great resolution that the IORs are ideal for zeroing in on long range targets & game.

Good shooting to all.

 

[Jon A]

Re: IOR SCOPES - light transmission ~ light gathering

I should have added on that subject:

I ended up using the 2.5-10X42 IOR last season and did use it quite a bit in low light. It did fine to beyond legal shooting light. While it's not as bright as the 50mm, it was certainly bright enough. That's what I was basing my expectations of the 3-18 on--I expect the 3-18 will be at least as good, maybe a bit better than the 2.5-10 in low light.

About the only thing that seemed lacking on the 2.5-10 as it was getting really dark, was I wouldn't have minded if the center lines of the reticle had been a bit thicker. The illuminated reticle version might have been better here (in Montana where it's legal).

The SFP 3-18 with the fine reticle is illuminated and the FFP 3-18 which won't be illuminated will have a thicker, bolder MP-8 so I think you're well covered either way with that one.

 

[Jeff In TX]

Re: IOR SCOPES - light transmission ~ light gathering

There's another way scope makers make their scopes brighter and is what you usually find on scope manufactures low end scope lines. I have no idea if this is what the Zeiss conquest scope line does this but I'm assuming they are.

Lower end scope manufacture will remove a series of internal lenses within the scope. What you gain is a very bright scope at a lower cost, what you loose is contrast and clarity. This is why some of the lower end scopes are much brighter than some of the top of the line scopes. But the contrast and clarity suffer, but they don't mention that in there adds. Zeiss uses much better glass than other scope lines in there price range and are probably able to gain some of the contrast and clarity back, but no where near that of a scope with a full set of high grade multi-coated lenses

I'm assuming this is what the Zeiss Conquest does to make their scopes bighter. I may be splitting hairs here, but Zeiss and IOR use basically the exact same optic coatings. The Conquest is a 1" tube design which is Zeiss's lower end scope line.

Still a great scope for the money.

 

[lefty15]

Re: IOR SCOPES - light transmission ~ light gathering

So would you recommend buying an IOR scope or should a guy maybe look at a Zeiss, Leupold or Nikon?

 

[jwp475]

Re: IOR SCOPES - light transmission ~ light gathering

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So would you recommend buying an IOR scope or should a guy maybe look at a Zeiss, Leupold or Nikon?

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I'd also take a look at Nighforce........I can not comment on the IOR's as I have no experience with them........

 

[RHutch]

Re: IOR SCOPES - light transmission ~ light gathering

Lefty,
Unless I missed it, you did not specify what the primary purpose of the scope would be...hunting or paper punching?
All the scopes mentioned are fine and will work. I own/owned all of them plus a few.
IMO, if low light capability is a must, look at the Zeiss Diavari line. The IOR(3-18 and 2.5-10) are very nice but I have yet to hunt late with them.