March Scopes

[Ironworker]

YouTube video Of March scopes at Shot show, the tech person said their scopes have Fluorite Glass, what is that?

 

[Rwfish]

Fluorite lenses: Corrective capabilities beyond the limits of ordinary optical glass - Canon Camera Museum

Canon developed its own technology for forming large, high-purity artificial fluorite crystals using fluorite ore as a raw material.

global.canon

 

[Rank Amateur]

I believe March advertises using Super ED lenses in their top-of-the-line “High Master Series” scopes.

​

"The Super ED lens element is an improved ED lens element with optical characteristics even closer to pure fluorite crystal lens elements. Pure fluorite crystals have virtually no dispersion that result in chromatic aberration in the image. By using Super ED lens elements, we can suppress chromatic aberration even more than with ED lenses and thus produce a sharper image with greater contrast, while still having a strong scope."​

​

I don’t think they are actually using pure fluorite crystal lens elements.​

 

[Turbulent Turtle]

What @Rank Amateur wrote is correct. The High Master series uses Super ED glass, which is essentially CaF2 (calcium fluorite) in a matrix. In other words, there's a lot of CaF2 in Super ED lens but it's much stronger than pure fluorite while having an Abbe number that's almost the same. Pure fluorite crystal doesn't lend itself well to riflescopes because it is fragile and subject to variations in temperature. The Kowa Prominar series spotters use pure fluorite crystal, but spotters are not subjected to the same treatment as riflescopes.

 

[Ironworker]

What @Rank Amateur wrote is correct. The High Master series uses Super ED glass, which is essentially CaF2 (calcium fluorite) in a matrix. In other words, there's a lot of CaF2 in Super ED lens but it's much stronger than pure fluorite while having an Abbe number that's almost the same. Pure fluorite crystal doesn't lend itself well to riflescopes because it is fragile and subject to variations in temperature. The Kowa Prominar series spotters use pure fluorite crystal, but spotters are not subjected to the same treatment as riflescopes.

March says the same glass in the High Master (Super ED Glass) series is also in my March FX 5-42x56mmG2. Is this glass as good as Top tier Schott Glass?

 

[Rank Amateur]

I’ve seen scope manufacturers make quality claims about their products regarding use of Schott Glass. Schott is a manufacturer. They produce hundreds of products including glass and ceramics. Even their offerings of aspherical optics can use dozens of glass types. The eventual properties of finished lenses come from combinations of “glass” materials, grinding/polishing precision, and coatings, even before combinations of lens elements are put together to result in the desired optical instrument. The use of Schott glass doesn’t necessarily yield better scopes (nor would use of Schott glass create ANY limitation for the best quality optics). I’m also not sure there are formal industry-wide definitions of “ED” or “Super ED”, so one manufacturer’s Super ED lens elements may not be comparable to that from a different manufacturer. This just makes it difficult for all of us to compare scopes, especially between manufacturers.

 

[tvaught]

This just makes it difficult for all of us to compare scopes, especially between manufacturers.

Seems like we should just look through the scopes and see which ones work best for us as individuals.

 

[Ranger188]

Seems like we should just look through the scopes and see which ones work best for us as individuals.

This^^^
I wish all shooters would just do this.

 

[ctrickett]

I have several March 2.5-25 scopes, use them for 200-600yd high power matches, they are great, dependable and awesome glass. Recently got a 10-60 High Master,(it has that special glass coating) I was blown away with difference, it cuts a lot of bubbly mirage out....side by side with the first scope I mentioned there is a big difference.

 

[Turbulent Turtle]

March says the same glass in the High Master (Super ED Glass) series is also in my March FX 5-42x56mmG2. Is this glass as good as Top tier Schott Glass?

The High Master glass is the same for the 10-60X56 HM, the Majesta, the FX 5-42X56, and the March-FX-4.5-28X52. I do not know what is in the various types and grades of Schott glass, so I won't speak to it.

Let me just say that the world of optical glass is complex and purposefully shrouded in mystery, intrigue and misdirection. People get hung up on names and the mystique that goes with some. Just remember that Japan has been making superb optical glass for a very long time. For example, in the days of yore, National Geographics only used Nikon cameras and lenses. I haven't a clue if that's still the case. You see a lot of Canon lenses at various venues, they are the big egg-white lenses priced in the 6 figures. We moan about a Majesta costing $4000, a lens from Canon or Nikon will set you back $15,000. I'm sure there are many other examples and probably pricier ones, but you get the gist.

Riflescope makers will rarely reveal the provenance of their glass, but some will say Schott and think that will be a mic drop moment. It really isn't for people who know.

 

[Turbulent Turtle]

This^^^
I wish all shooters would just do this.

I don't disagree but it's usually not possible to do a proper comparison. The best one can try to do is compare the image of the target at a match, if the owner of the scope you are wanting to look through would allow that. Thankfully most people will be more than happy to do that.

If you do have the occasion to compare by looking through someone else's scope, make sure you have set it at the same magnification as the one your riflescope is set. Ask the owner which magnification (s)he uses and maybe look through it at that magnification. I still remember the time when someone looked through my Majesta set at 80X, and compared it to his own riflescope set at 55X and could not really grasp the difference. When I told him to set the Majesta at 55X, he understood the difference. The Majesta needs to be at 73X to show the same narrow FOV of his 55X riflescope.

Remember, your brain is a pattern recognition machine and it fills in a lot from what the eye sends it. People will set the new scope to present the same view as the old one, because that's what they are used to.

I've written a whole chapter on comparing scopes, and it's complex.

 

[Turbulent Turtle]

I have several March 2.5-25 scopes, use them for 200-600yd high power matches, they are great, dependable and awesome glass. Recently got a 10-60 High Master,(it has that special glass coating) I was blown away with difference, it cuts a lot of bubbly mirage out....side by side with the first scope I mentioned there is a big difference.

The 10-60X56 HM doesn't have a special glass coating that makes it better than the 2.5-25X42/52; it has Super ED lenses compared to the ED lenses of the 2.5-25X. BTW, I love that 2.5-25X model.

The Abbe number of Super ED glass is just a fraction below pure fluorite crystal, and I mean a fraction of a point. I cannot detect any chromatic aberration (CA) in the HM or my Majesta.

 

[Ironworker]

I've carefully created a concise analytical summary of my new March scope, and it's clear that it’s "Bad to the Bone." LOL

 

[Turbulent Turtle]

I’ve seen scope manufacturers make quality claims about their products regarding use of Schott Glass. Schott is a manufacturer. They produce hundreds of products including glass and ceramics. Even their offerings of aspherical optics can use dozens of glass types. The eventual properties of finished lenses come from combinations of “glass” materials, grinding/polishing precision, and coatings, even before combinations of lens elements are put together to result in the desired optical instrument. The use of Schott glass doesn’t necessarily yield better scopes (nor would use of Schott glass create ANY limitation for the best quality optics). I’m also not sure there are formal industry-wide definitions of “ED” or “Super ED”, so one manufacturer’s Super ED lens elements may not be comparable to that from a different manufacturer. This just makes it difficult for all of us to compare scopes, especially between manufacturers.

Let's see if we can wade our way through this. As I have mentioned before, riflescopes manufacturers will usually not reveal the provenance of the glass they use. Some of them will drop names like Schott, but that is meaningless as Schott glass is made all over the world and in varying specs, grades, etc. Even beyond the glass itself, there's grinding, polishing, coatings, setup, installation and so on. If the design is bad, the best glass in the universe won't help it. The optical design engineer is critical to the overall product. If you get a riflescope that is made by a third party, regardless of who it is, they will work to specs and lowest cost to ft the specs. On the other hand, manufacturers who make their own riflescopes and sell them are more apt to design as they want it, rather than how the 3rd party would make them.

Now to the difference between ED and Super ED. I think I've mentioned this elsewhere, but let me do it here again. My understanding from my independent research (nice CYA) is that ED glass is essentially optical glass with some rare earth elements mixed into the glass. This is beyond what it used for coating. On the other hand, Super ED glass is mainly composed of pure fluorite crystal glass that is incorporated into a glass matrix to make the CaF2 much stronger compared to just pure fluorite crystal glass, and it can also have some rare earth elements in the formula. As we all know CaF2 is the most CA-resistant material for lenses with a high Abbe number. Super ED glass can have an Abbe number virtually as high as the one for CaF2.

tl;dr:
ED Glass: addition of rare earth elements for a better Abbe number than optical glass.
Super-ED glass: uses Caf2 in a glass matrix and can also have some rare earth elements in the formula for an Abbe number virtually identical to pure CaF2.

Now we can see why ED and especially Super ED glass is so expensive.

 

[Ironworker]

Let's see if we can wade our way through this. As I have mentioned before, riflescopes manufacturers will usually not reveal the provenance of the glass they use. Some of them will drop names like Schott, but that is meaningless as Schott glass is made all over the world and in varying specs, grades, etc. Even beyond the glass itself, there's grinding, polishing, coatings, setup, installation and so on. If the design is bad, the best glass in the universe won't help it. The optical design engineer is critical to the overall product. If you get a riflescope that is made by a third party, regardless of who it is, they will work to specs and lowest cost to ft the specs. On the other hand, manufacturers who make their own riflescopes and sell them are more apt to design as they want it, rather than how the 3rd party would make them.

Now to the difference between ED and Super ED. I think I've mentioned this elsewhere, but let me do it here again. My understanding from my independent research (nice CYA) is that ED glass is essentially optical glass with some rare earth elements mixed into the glass. This is beyond what it used for coating. On the other hand, Super ED glass is mainly composed of pure fluorite crystal glass that is incorporated into a glass matrix to make the CaF2 much stronger compared to just pure fluorite crystal glass, and it can also have some rare earth elements in the formula. As we all know CaF2 is the most CA-resistant material for lenses with a high Abbe number. Super ED glass can have an Abbe number virtually as high as the one for CaF2.

tl;dr:
ED Glass: addition of rare earth elements for a better Abbe number than optical glass.
Super-ED glass: uses Caf2 in a glass matrix and can also have some rare earth elements in the formula for an Abbe number virtually identical to pure CaF2.

Now we can see why ED and especially Super ED glass is so expensive.

Thanks, that was fascinating, you answered questions I never knew I had.

 

[Ironworker]

Zero Compromise scopes glass is called Extra-Low Dispersion glass. What is that ?

 

[Ranger188]

@Turbulent Turtle
"Extra low dispersion"
Have you explored this terminology?

 

[Turbulent Turtle]

Zero Compromise scopes glass is called Extra-Low Dispersion glass. What is that ?

That is ED glass, Extra-low Dispersion.

 

[tvaught]

I don't disagree but it's usually not possible to do a proper comparison. The best one can try to do is compare the image of the target at a match, if the owner of the scope you are wanting to look through would allow that. Thankfully most people will be more than happy to do that.

If you do have the occasion to compare by looking through someone else's scope, make sure you have set it at the same magnification as the one your riflescope is set. Ask the owner which magnification (s)he uses and maybe look through it at that magnification. I still remember the time when someone looked through my Majesta set at 80X, and compared it to his own riflescope set at 55X and could not really grasp the difference. When I told him to set the Majesta at 55X, he understood the difference. The Majesta needs to be at 73X to show the same narrow FOV of his 55X riflescope.

Remember, your brain is a pattern recognition machine and it fills in a lot from what the eye sends it. People will set the new scope to present the same view as the old one, because that's what they are used to.

I've written a whole chapter on comparing scopes, and it's complex.

This post is worth reviewing.

I'd also emphasize/add that our "sight picture" (the thing we perceive in our brain of a given image/feature) is a Learned Cognitive Behavior/Experience.

i.e. We are better with whatever optic the more time we have with it.

This might help explain the "oh wow" or the "oh no" experience you might initially have with a new to you set of binos, spotter, or scope, even after its all properly setup for eye relief, diopter, and parallax.

It might take a couple looksies and some time for our brains to fully realize what a given optic may or may not offer us.

Or at least that is what Grok says. Allegedly.