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March Scopes is the Pioneer in the use of ED lens, Super ED lens, Temperature anti-drift lens system. Classification of March Scopes by lenses

Posted 09/13/2021

Lenses are one of the most important aspects of any rifle scopes. They are one of the most expensive components to produce. The clearer the lens, the clearer the image. Unfortunately, it’s also one of the most difficult parts of a scope to assess. Even if you can look through a scope in a store, it’s difficult to find out how clear the lens is. At DEON (manufacturer of March Scopes), we try to seek the very best Japanese made lenses that meet up to March standards searching even outside the optics industry in order to provide the best scopes ever.

 

DEON is the pioneer in using ED lens, Super ED lens, Temperature anti-drift lens system in riflescopes. All current production March riflescopes except for the 24mm objectives have at least ED glass. We also use the top quality multi-coating where the transmittance is very near 100% having the effect of presenting very natural colors, and high overall light transmittance. You can learn the details below and at the bottom I have stated “(5)Classification of March Scopes by lenses” so you can easily tell which model adopts what kind of lenses.

(1) ED lens

ED stands for Extra-low Dispersion. ED lens disperses light less than ordinary lens and reduces chromatic aberration. Chromatic aberration normally appears when you are looking at a white object such as a white swan. There will be a color blur at the border line between the white object and the background. To reduce chromatic aberration, we incorporate ED lens for most of our scopes though they are more expensive than ordinary lens.

13 years ago, when we assembled ED lens into the newly launched 40×52 Benchrest scope, ED lens was not used in any other riflescopes then. (*40×52 is no longer available and has been upgraded to 48×52) At that time, ED lens was only used in cameras, high magnification telescopes, and high-end spotting scopes. March Scopes was the first riflescope manufacturer to adopt ED lens. We have started the trend and now other scope manufacturers use ED lens for high magnification and high-end scopes.

 

(2) Super ED lens

Incredible Super ED lens formula is closer to fluorite than ED lens for superior correction of chromatic aberration. The resulting sight picture provides unsurpassed edge to edge definition and renders color in true-to-life hues across the entire field of view. 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. Super ED lens was first developed by Nikon to use in a camera. March Scopes is the first to adopt the Super ED lens and is still the only scope manufacturer assembling it in riflescopes.

In 2017, we started adopting Super ED lens for High Master model March Scopes. Our High Master models (SFP : 48×52, 40-60×52,10-60×56, FFP : 4.5-28×52, 5-42×56, 4-40×52, 6-60×56) are favored by many shooters. This is because the High Master Lens System adopted in all the High Master models exhibits outstanding clarity. The High Master Lens System incorporates 2 Super ED lens elements within its lens system.

(* Note : Wide Angle series 4.5-28×52 and 5-42×56 have compact scope bodies. Their shortness brings in more chromatic aberration and to control that we use the Super ED lenses (High Master lens system) in them.)

We use either ED lens or Super ED lens for all March Scopes except for scopes with 24mm objective lens. These are scopes with lower magnification. When at lower magnification, it is harder to find a chromatic aberration. There is hardly any difference in chromatic aberration between ED lens and normal lens when it comes to scopes with 24mm objective lens. That is why we use normal lens for scopes with 24mm objective lens. However please be assured that we only use top quality Japanese made lenses for normal lenses as well.

(3) Temperature Anti-Drift Lens System

We have also been successful in developing a Temperature Anti-draft Lens in 2019. We are the first and the only manufacturer to assemble a Temperature Anti-draft Lens. This project started a few years ago when we received a request from Field Target shooters who are sensitive to subtle temperature change. In the latest optical systems for automotive cameras, a new lens material has been developed to accommodate changes in environmental temperature by altering the refractive index of the lenses. This new lens material has been adopted for the new High Master model March Scopes to create a more stable lens system that naturally adapts to changes in temperature to maintain focus and clarity over a wide range of conditions. We try to adopt the best glass ever searching even outside the optics industry. 

 

Comparison with March Scope 10-60×56 High Master

(1) Before : High Master lens system without Temperature Anti-drift Lens

◆Temperature change : 35 degrees Celsius difference

   25 degrees Celsius (77 degrees Fahrenheit) → minus 10 degrees Celsius (14 degrees Fahrenheit) 

◆Change in focal point

   ∞(infinity) → 350m (about 383yard)

When there is a 35 degrees Celsius difference, the focal point first set at ∞(infinity) will be shifted to 350m (about 383 yard). 

(2) After : High Master lens system with Temperature Anti-drift Lens

◆Temperature change : 35 degrees Celsius difference

   25 degrees Celsius (77 degrees Fahrenheit) → minus 10 degrees Celsius (14 degrees Fahrenheit) 

◆Change in focal point

   ∞(infinity) → 1.3km (about 1422 yard)

It may be easy to see the change between infinity and 350m, but it is very difficult for a human eye to detect the difference between infinity and 1.3km. Some people may not feel any focal difference. (*Above is an example based on calculation. When inputting different values, there will be a different result.)

 

The newly developed  High Master lens system with Temperature Anti-drift Lens incorporated within 10-60×56, 4.5-28×52, 5-42×56, 4-40×52, 6-60×56 High Master models is way less sensitive to temperature difference than ever. This new system will naturally adapt to changes in temperature to maintain focus and clarity over a wide range of conditions. (*Fixed 40-60x52High Master and 48x52High Master do not incorporate Temperature Anti-draft Lens in their High Master lens system as they have less lenses and therefore less susceptible than other High Master models.

 

(4) Lens Coating

Most riflescope manufacturers say that their optics are multi-coated. The term “multi-coating” is somewhat misleading as anything having more than three layers is, by definition, “multi-coated.” The issue is that in order for the riflescope to properly render the colors across the entire visible spectrum, there have to be many coatings, each one designed for a portion of the visible spectrum. If there are only a few layers, the riflescope will display a tint (for example: greenish color) and the overall light transmission will not be what you would expect, since the light from the other colors is reduced. As more coatings are applied, the color fidelity and the overall light transmittance both increase.

Generally, the light transmittance figure will be:

  • One lens surface without a coat : 96%

  • Single layer of coating : 98.5%

  • Fully multi-coated (more than 3 layers) lens : 99.5%

(General example) Using a multi-coat with the transmittance of 99.5% for all lens elements, then as lenses are added in the optical path, we can calculate the overall transmittance by using the number of lenses in the following equation: OT = .995 ** L, where OT is overall light transmission and L is the number of lenses in the path. So if a riflescope has 20 lenses, the overall light transmission is calculated as .995**20 or 90.5%.

 

For all March Scopes we only use top quality multi–coating where the transmittance is very near 100%. This also has the effect of presenting very natural colors, and high overall light transmittance.

(5) Classification of March Scopes by lenses

When you click the model in blue, it will jump to the product page.

56mm Objective lens : SFP   5-50x (ED)

                                              10-60x (Super ED : High Master / Temperature Anti-drift Lens)

                                              8-80x (ED)

                                              8-80x (Super ED : High Master / Temperature Anti-drift Lens)

                                     FFP   5-40x (ED) , 5-40x Genll (ED) 

                                              5-42x Wide Angle (Super ED : High Master / Temperature Anti-drift Lens)

                                              6-60x Genesis (Super ED : High Master / Temperature Anti-drift Lens)

52mm Objective lens :  SFP  2.5-25x (ED)

                                              10-60x (ED) 

                                              48x Fixed (Super ED : High Master) 

                                              40-60x EP Zoom Fixed (Super ED : High Master) 

                                     FFP   3-24x (ED)  

                                              4.5-28x Wide Angle  (Super ED : High Master / Temperature Anti-drift Lens)

                                              4-40x Genesis (Super ED : High Master / Temperature Anti-drift Lens)

42mm Objective lens :  SFP  1.5-15x (ED)

                                              2.5-25x(ED)

                                      FFP  1.5-15x (ED)

                                               3-24x (ED)   

24mm Objective lens :  SFP  1-4x, 1-4.5x, 1-10x   

                                      FFP  1-8x, 1-8x Shorty, 1-10x Shorty     

(* Note : Wide Angle series 4.5-28×52 and 5-42×56 have compact scope bodies. Their shortness brings in more chromatic aberration and to control that we use the Super ED lenses (High Master lens system) in them.)

 

We try to adopt the best glass ever searching even outside the optics industry in order to support shooters by providing the very best scopes on which you can rely on at all times.

Written by : Mari Morita

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