# True lens magnification



## JMJ (Jul 17, 2008)

Have any of you guys looked at this?
http://www.sureloc.com/scopes/diopter.html

Is it accurate?


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## JayMc (Jan 4, 2005)

I think it's accurate and it definitely makes sense. My focal length is short like my DL and inseam. My 6X lens has the same perceived magnification as my buddy's 4X due to focal length differences.


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## JMJ (Jul 17, 2008)

So do you think it would apply to ANY lens?

If so, how can anyone claim that a .50 diopter = 4x magnification?
I don't think I've ever known anyone with a 59" span from the eye to the lens ... ???


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## JayMc (Jan 4, 2005)

It has to apply to every lens. The perceived magnification is a function of diopter and focal length. The peep assists in focusing the image, but doesn't really change magnification. A clarifier will reduce perceived magnification.


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## TN ARCHER (Jan 31, 2007)

JayMc said:


> It has to apply to every lens. The perceived magnification is a function of diopter and focal length. The peep assists in focusing the image, but doesn't really change magnification. A clarifier will reduce perceived magnification.


Jay is correct. Just to add, the clarifier is the negative that clears up the positive. This causes some lose in perceived magnification.


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## JMJ (Jul 17, 2008)

ok thanks guys ...

I noticed that Specialty rates their lenses in magnification powers, but in the FAQ it tells you that they're rated @ 34".
I just switched out my scopes from a Classic w/ .50 to a SuperScope of 2x. Sure enough, the lowly 2x is just as magnified, and a bit clearer, than the "claimed" 4x of the .50 Classic.

My focal distance is set up @ 35".
Looks like I'll be in the market for a new scope & lens.

BTW ... missed you guys at our shoot last month.
I was looking forward to the Lebanon crew coming for a visit.
Maybe next year!


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## TN ARCHER (Jan 31, 2007)

JMJ said:


> ok thanks guys ...
> 
> I noticed that Specialty rates their lenses in magnification powers, but in the FAQ it tells you that they're rated @ 34".
> I just switched out my scopes from a Classic w/ .50 to a SuperScope of 2x. Sure enough, the lowly 2x is just as magnified, and a bit clearer, than the "claimed" 4x of the .50 Classic.
> ...


Where are you from JMJ?


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## JMJ (Jul 17, 2008)

Here ...

http://www.dcsarchery.com


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## JayMc (Jan 4, 2005)

I shot with the father/son from DCS at Broken Arrow one day. Great guys!

JMJ - are you them or do you shoot there?


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## JMJ (Jul 17, 2008)

That would be me & my son .. 

I remember the story you told of how your father won't let you drive when he's with you. lol


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## JayMc (Jan 4, 2005)

JMJ said:


> That would be me & my son ..
> 
> I remember the story you told of how your father won't let you drive when he's with you. lol


He got over it a bit this spring. We (Dad, brother and me) went to NW Nebraska turkey hunting. I drove from TN to LA to meet them then we headed north. He sure enough let me drive 3/4 of the way from south LA to NE


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## Brown Hornet (Aug 8, 2002)

Not everyones powers are created equal either.... I found Sure Locs stuff to be VERY weak in comparison to others power wise. Brite Site is strong....

Speaking of power....time to get a new Hornet Edition lens from DY... I need a 6X it's indoor time


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## brtesite (May 24, 2002)

JayMc said:


> I think it's accurate and it definitely makes sense. My focal length is short like my DL and inseam. My 6X lens has the same perceived magnification as my buddy's 4X due to focal length differences.


Your focal length is your focal length. You can not change the focal length of the lens. It is what it is. What you are changing , is the distance from your eye to the lens.
More distance , more magnification. & visaversa


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## JayMc (Jan 4, 2005)

brtesite said:


> Your focal length is your focal length. You can not change the focal length of the lens. It is what it is. What you are changing , is the distance from your eye to the lens.
> More distance , more magnification. & visaversa


I meant my 6X at my eye to lens length on my bow and his 4X at his eye to lens length on his bow. Sorry if it wasn't clear.


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## FS560 (May 22, 2002)

This is something that has bugged me for years, and still does. I can relate to diopter but not to scope purveyors calling their lens by some obscure value of X power. I know that a .5 diopter is a .5 diopter. Apparently, they think that the majority of archers are stupid. JFC, I just answered my own question. Sorry!


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## JMJ (Jul 17, 2008)

FS560 said:


> Snip .... Apparently, they think that the majority of archers are stupid. JFC, I just answered my own question. Sorry!


Well if the chart & calculator on sureloc's website are indeed acurate ...

It has become painfully obvious that this archer, (me), was in fact stupid!
Although I'd prefer to call it "uninformed." :embara:
I've always thought that 4x meant 4x, 2x meant 2x, so on and so on.

I always preach to my family about NOT becoming a victim of marketing hype.
Well guess who they get to preach to now! :embara:

Just as an additional step, I carried some lenses I have to an optometrist(sp?) this morning.
They checked them and they are indeed the diopter as they are marked, but I never knew this didn't mean they were the magnification power they were marked.
We discussed the possiblity of HIM making lenses in the future. At least that way maybe I'll know what the hell I've got stuck in my housing. LOL


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## bownarra (Aug 31, 2008)

Good thread JMJ! This frustrates the heck out of me too. 

I have a cheap lens in my cheap no-name scope, took it to my optometrist who measured it at 0.5 diopter. According to sure-loc's table that should make it a bit less than 2x magnification. 

Now I want a bit more power so you'd think a 4x lens would do the trick, right? Nope, most manufacturers' 4x lenses are also 0.5 diopter, exactly what I have already.



Brown Hornet said:


> I found Sure Locs stuff to be VERY weak in comparison to others power wise.


How is this possible? Sure-Loc's 4x must be about a .7 or .8 diopter, everyone else's 4x is a .5 diopter. How can Sure-Loc lenses appear weaker? I'm not arguing with you, (I've never compared them side by side), just trying to get my head around this.

Sure-loc says different manufacturers measure their diopters differently. Could it be that they 'rate' theirs with higher diopter values than everyone else?


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## JMJ (Jul 17, 2008)

bownarra said:


> Good thread JMJ! This frustrates the heck out of me too.
> 
> I have a cheap lens in my cheap no-name scope, took it to my optometrist who measured it at 0.5 diopter. According to sure-loc's table that should make it a bit less than 2x magnification.
> 
> ...


I'm convinced there's much more we don't know about this stuff.
While at the optometrist this morning, one of the girls pulled out an eyeglass blank that was .5 diopter.
At arm's length, the eyeglass blank @ .5 had quite a bit more magnification than the Zeiss .5 that I carried with me.
I suppose it's worth mentioning that the Zeiss is flat glass.
The eyeglass blank was convexed polycarbonate.

I'll keep digging at it ... so should you!


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## TN ARCHER (Jan 31, 2007)

JMJ said:


> I'm convinced there's much more we don't know about this stuff.
> While at the optometrist this morning, one of the girls pulled out an eyeglass blank that was .5 diopter.
> At arm's length, the eyeglass blank @ .5 had quite a bit more magnification than the Zeiss .5 that I carried with me.
> I suppose it's worth mentioning that the Zeiss is flat glass.
> ...


I was told by True Spot that you cannot have any magnification without having some convex/ concave in the glass. Even so called "flat glass" has slight convex shape. Just what I was told.


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## JMJ (Jul 17, 2008)

http://www.howardelectronics.com/HEIScope/illumination/diopter.html

http://eyesee-eyetalk.blogspot.com/2007/11/what-is-diopter.html


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## Ohio_3Der (Jul 19, 2002)

The guy at classic laughed at me when I called a particular lens "flat glass." He said that there has got to be a curve somewhere. He said "flat glass" is a window.  I guess I'd have to agree with that. ha ha 

This diopter/power rating is an old deal. I used to shoot a "6X" super scope, so when I wanted to try something new I went with a "6X" Britesite lens. Well, as some of you know, and now I do to, a "6X" britesite is a 1.0 diopter. This was stronger than my current super scope, and I later found out that my "6X" super scope was just a 0.75 diopter. So, now I either shoot a 6x britesite, or a 8x super scope (or just about anything else out there).


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## brtesite (May 24, 2002)

TN ARCHER said:


> I was told by True Spot that you cannot have any magnification without having some convex/ concave in the glass. Even so called "flat glass" has slight convex shape. Just what I was told.



what he said.


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## brtesite (May 24, 2002)

Ohio_3Der said:


> The guy at classic laughed at me when I called a particular lens "flat glass." He said that there has got to be a curve somewhere. He said "flat glass" is a window.  I guess I'd have to agree with that. ha ha
> 
> This diopter/power rating is an old deal. I used to shoot a "6X" super scope, so when I wanted to try something new I went with a "6X" Britesite lens. Well, as some of you know, and now I do to, a "6X" britesite is a 1.0 diopter. This was stronger than my current super scope, and I later found out that my "6X" super scope was just a 0.75 diopter. So, now I either shoot a 6x britesite, or a 8x super scope (or just about anything else out there).


I have been making scopes since 1977, Long before any present scopemanufacturer. Had the first lighted scope , had the first lense coatings
&had the first 3rd axis compensator on the market . I used to mark all my scopes in diopters. Got tired of trying to explain to the world what it was. They always asked the power. So I just asigned a power rating to them. I used to pass out the nomagaph with the apparant power Vs diopter.
Then one of my competitors started asigning a power rating one level under mine for marketing purposes. His 4x was more clear than mine , because it was weaker.

Yes mine are still stronger than the others. My 6x is 1.0 d, 4x is .80d , 2x .60d


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## Ohio_3Der (Jul 19, 2002)

brtesite said:


> I have been making scopes since 1977, Long before any present scopemanufacturer. Had the first lighted scope , had the first lense coatings
> &had the first 3rd axis compensator on the market . I used to mark all my scopes in diopters. Got tired of trying to explain to the world what it was. They always asked the power. So I just asigned a power rating to them. I used to pass out the nomagaph with the apparant power Vs diopter.
> Then one of my competitors started asigning a power rating one level under mine for marketing purposes. His 4x was more clear than mine , because it was weaker.
> 
> Yes mine are still stronger than the others. My 6x is 1.0 d, 4x is .80d , 2x .60d


Just playing with you, but you'd think a guy making scopes since 1977 in America could spell "lens." 

Jeremiah


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## JMJ (Jul 17, 2008)

Ohio_3Der said:


> The guy at classic laughed at me when I called a particular lens "flat glass." He said that there has got to be a curve somewhere. He said "flat glass" is a window.  I guess I'd have to agree with that.


I would agree with that as well.



brtesite said:


> Yes mine are still stronger than the others. My 6x is 1.0 d, 4x is .80d , 2x .60d


Thanks for that.
When I get ready for another lens, I'll make sure to consider yours.


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## brtesite (May 24, 2002)

Ohio_3Der said:


> Just playing with you, but you'd think a guy making scopes since 1977 in America could spell "lens."
> 
> Jeremiah


 got your attention didn't it?


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## Ohio_3Der (Jul 19, 2002)

*ha ha*

Touche. :wink:

By the way, I shoot your tuner, your clarifier peep, and sometimes your lenses. Good stuff.


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## avid3d (Jun 23, 2002)

i had a conversation with bert at feathervision recently and he told me the chart at sureloc is very accurate. when i started into target archery, i bought a specialty archery scope with a lens marked 4x. my friend shot one marked 6x and it had too much movement for me so i always thought i shot 4x. after looking at the chart, i find out i'm actually a 2x guy. who knew? 

seems to me mike's numbering is pretty accurate, unless someone is shooting a scope pushed waaaaay out there.


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## Brown Hornet (Aug 8, 2002)

What's your definition of "way out there"?

Are you one of those guys that shoots a bar pulled in? I shoot a long bar and I use it :wink:


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## Ohio_3Der (Jul 19, 2002)

Speaking of all these advertised "powers." What are the diopters of the clarifiers out there? And, how does these clarifiers adjust the perceived "power" via the Sure loc chart? I shoot a 6x britesite scope inside, it's a 1.0 diopter. My sight length is 35 inches. The sure loc table say it's about a 7-8 Power. I have a britesite OBS clarifier peep. What is my perceived "power" now? 

What if I changed to a SAP yellow/green/red clarifier? How would those be different in terms of perceived "power" as is referred to on the sure loc chart?


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## tonygoz (May 1, 2013)

tag


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