On the 36x55 EP-ZOOM model can you focus the eyepiece on this model ? Also how does the clarity of the March Straight 40x compare to the above variable. I never looked through a march and just getting started in benchrest and with bullets.com offering 15% off these scopes I think i should take advantage of the offer. One of my friends said his competition leupold is clearer, but even if it is i like the 3/32 dot as opposed to the leupold 1/8 dot and with the tracking of the march i told him i can put up with a little less clarity if thats true for the advantages mentioned above. Your opinions please?
March Scope Question
- Thread starter btc624
- Start date
Lee Martin
Active member
I can't answer your question on the 36x55, but my 40X March is every bit as clear as my three Leup Comps. And like you I chose the 3/32" dot, which is working well for me.
-Lee
www.singleactions.com
-Lee
www.singleactions.com
jackie schmidt
New member
The only March Scopes that have, (had) issues with clarity are the older 50x fixed Benchrest Scopes. I have two, from the very first year of production, and you can easily tell that March missed something on the glass. But, that being said, they are rock solid on both my LV 6PPC and my 30BR HV, so I use them.
The March 40x scopes, and the variables, while maybe not being as clear as a Comp Leupold, are pretty darned good.
The March 40x scopes, and the variables, while maybe not being as clear as a Comp Leupold, are pretty darned good.
Andy Cross
New member
An interpretation on clearer
As an optical engineer I would like to take this opportunity to get some shooters interpretation on what they mean by clearer.
For example one scope has higher resolving power as in line pairs per mm
or
Lower flare factor
or
Higher level of contrast
or
better light transmission ie brighter image
or
???????
helps me better understand what shooters are talking about in general conversation.
Andy.
As an optical engineer I would like to take this opportunity to get some shooters interpretation on what they mean by clearer.
For example one scope has higher resolving power as in line pairs per mm
or
Lower flare factor
or
Higher level of contrast
or
better light transmission ie brighter image
or
???????
helps me better understand what shooters are talking about in general conversation.
Andy.
Fred Bohl
Retired Engineer
March 36x55 EP-ZOOM
In answer to the OP first question - yes the eyepiece has the usual focus (diopter) correction in addition to the zoom adjust.
An old reference from the original Deon Optical site said that the 36x55 EP-ZOOM was based on the 50x fixed with the new eyepiece. Having both I can attest that the optical performance of both is equal.
+3 at least to post by Andy Cross. These forums are in desperate need of a glossary that would establish definitions for the special use we make of language as applied to our sport. This is particularly true in optical performance description were we need objective measurements. Oddly, the human visual system is plagued by variability from individual to individual and within a individual by age, time and conditions and therefor is a very poor instrument for comparison of optical performance.
In answer to the OP first question - yes the eyepiece has the usual focus (diopter) correction in addition to the zoom adjust.
An old reference from the original Deon Optical site said that the 36x55 EP-ZOOM was based on the 50x fixed with the new eyepiece. Having both I can attest that the optical performance of both is equal.
+3 at least to post by Andy Cross. These forums are in desperate need of a glossary that would establish definitions for the special use we make of language as applied to our sport. This is particularly true in optical performance description were we need objective measurements. Oddly, the human visual system is plagued by variability from individual to individual and within a individual by age, time and conditions and therefor is a very poor instrument for comparison of optical performance.
Dick Grosbier
Club Coordinator
Andy
I do not know the technical terms, I just know when I adjust the focus on a scope I want to see the lines on the target get nice and crisp. If when adjusting a scope it is approaching clear but then gets worse before it gets crisp I say the scope is not sharp. Contrast is important also.
Last edited:
Rex Reneau
New member
In over 35 years of shooting benchrest, I have owed about every scope out there. Lyman, Leupold 24,36 and 45, Sightron, Weaver and March. I got one of the original shipment of 40s. Excellent. Got a 50, good but not excellent optically but excellent holding POI. Tried a 60 with dot, didn't work for me. Then Turk showed me a 36-55. Best scope I have ever had. I still have original 40 but now have two 36-55s. At the Cactus, Turk had me look through a 36-55 that a shooter said wasn't clear, I ask if I could adjust rear eye piece and guess what. He said it was fine. If I could only have one scope, it would be a 36-55. Optics are great but but the most important thing is holding point of impact.
Andy Cross
New member
Totally agree
Totally agree that's why becoming knowledgable with the terminology is important if the people fixing the instrument are to get it right. Many times in the lab we would get an optical instrument in with the client using the term not clear or sharp etc. When tested the device was spot on. So we did nothing but said the issue was addressed. Feed back was thankyou it's fixed. Chances are that persons eyes were affected in some way but didn't re-occur at the time it was sent back. Rarely were the people who were complaining about something like this under the age of 30. Umm there is definitely something to this.
Andy.
Totally agree that's why becoming knowledgable with the terminology is important if the people fixing the instrument are to get it right. Many times in the lab we would get an optical instrument in with the client using the term not clear or sharp etc. When tested the device was spot on. So we did nothing but said the issue was addressed. Feed back was thankyou it's fixed. Chances are that persons eyes were affected in some way but didn't re-occur at the time it was sent back. Rarely were the people who were complaining about something like this under the age of 30. Umm there is definitely something to this.
Andy.
Boyd Allen
Active member
While it is obviously important for optical professionals to have exact ways of describing optical quality, and it certainly is desirable for purposes of precise communication, subjective evaluations of users, based on comparisons have value. After all the scopes are made for those end users, and it is their opinions that will ultimately determine the success or failure of a design.
I would agree with those that have said that the image of March fixed power scopes while quite usable, is not as good as that of the Leupold Competition scopes that I have looked through. I am quite familiar with how to set up a scope for my vision, and have spent a couple of range days, looking through a 40X March, helping a friend test loads for a specialty reloading manual. I have also spent some time behind a Leupold Competition. To me, the difference is readily apparent, but would not be the determining factor for purchasing a scope. The March was of sufficient optical quality, and it has a superior reputation for holding point of impact, and it is that feature that is the most important.
While I am not in the market for either at this time, what I would like to know is how the March stacks up with the new Night Force with regard to holding POI, since the Night Force has such outstanding image quality.
It may be that the issue with the March scope was depth of field of that particular optical design. For example there are universal focus binoculars (none of which, to my knowledge come near to top quality) that have a lot more depth of field at a given magnification than other designs of the same magnification that definitely require focusing.
With regard to the fixed March vs. Leopold Compition comparison, virtually everyone who I have asked who has looked through both agrees, but of course that does not mean that they are shooting a Leupold because image quality is not at the top of the list.
A while back, a couple of journeyman level shooters who are friends shared an insight with me. They had both been struggling with issues that were resolved by making changes in their scopes. One had bought a Brackney setup with a frozen Leupold Competition, in his external adjustable mounts, and the other had a March fixed power. According to them, both solutions worked and eliminated their unexplained shots.
I would agree with those that have said that the image of March fixed power scopes while quite usable, is not as good as that of the Leupold Competition scopes that I have looked through. I am quite familiar with how to set up a scope for my vision, and have spent a couple of range days, looking through a 40X March, helping a friend test loads for a specialty reloading manual. I have also spent some time behind a Leupold Competition. To me, the difference is readily apparent, but would not be the determining factor for purchasing a scope. The March was of sufficient optical quality, and it has a superior reputation for holding point of impact, and it is that feature that is the most important.
While I am not in the market for either at this time, what I would like to know is how the March stacks up with the new Night Force with regard to holding POI, since the Night Force has such outstanding image quality.
It may be that the issue with the March scope was depth of field of that particular optical design. For example there are universal focus binoculars (none of which, to my knowledge come near to top quality) that have a lot more depth of field at a given magnification than other designs of the same magnification that definitely require focusing.
With regard to the fixed March vs. Leopold Compition comparison, virtually everyone who I have asked who has looked through both agrees, but of course that does not mean that they are shooting a Leupold because image quality is not at the top of the list.
A while back, a couple of journeyman level shooters who are friends shared an insight with me. They had both been struggling with issues that were resolved by making changes in their scopes. One had bought a Brackney setup with a frozen Leupold Competition, in his external adjustable mounts, and the other had a March fixed power. According to them, both solutions worked and eliminated their unexplained shots.
Fred Bohl
Retired Engineer
Perceived Quality of High Power Telescopic Sights
This thread is another example of problems with the perceived versus actual quality of high power scopes and the lack of well-defined terminology to explain the issue. The following is offered to aid the discussion.
Key Definition 1 – Resolution is the smallest detectable angular separation of two of the smallest objects of interest.
Eyesight Resolution Limitations – The normal or median human visual resolution limit is 1 MOA (minute of angle). This is also called normal visual acuity when use by your eye doctor. On the typical Snellen eye chart, the 20/20 line (20 foot line in USA) or 6/6 line (6 meters in the rest of the world) was designed to be readable with a visual resolution or acuity of 1 MOA. The other lines/characters are scaled accordingly (20/10 or 6/3 line is 0.5 MOA resolution and 20/40 or 6/12 line is 2 MOA resolution).
Scope Function – Telescopic sights (erecting refraction telescope) were developed as visual aids to overcome this limited visual resolution or acuity. The principal tool for resolution improvement is magnification. It is obvious that magnification increases the apparent size of objects. However and more importantly magnification helps to increases visual resolution of small but important details by both increasing their apparent size and reducing the available field of view.
Scope Resolution Limitations – A long historical record holds that diffraction defines the ultimate resolution limit of telescopes. Generally we can say that any aperture with a finite size will cause diffraction and hence its resolution will be limited. The finite aperture (objective lens) must cut off a part of the incoming plane wave front. This missing part distorts the otherwise perfect interference of the propagating waves in a certain way. For the current available quality scopes the Dawes limit currently gives the best (as supported by many observations) working value for the best resolution that can be reasonably expected in shooting applications.
Dawes's Resolution Limit [MOA] = 1.933 / Objective Diameter [mm].
Also = Smallest separation between features and minimum POA (point of aim) error (confusion circle)!
Key Definition 2 – Match Magnification means the Dawes Limit equals the magnified normal visual acuity of the human eye. At less magnification the scope resolution is limited by the user's visual acuity. Above match magnification the scope resolution is diffraction limited by the objective diameter to the Dawes Resolution Limit.
Match Magnification = Visual Acuity [MOA] / Dawes's Resolution Limit [MOA]
Magnifications greater than the match to Dawes Limit do not produce any more real resolution and has sometimes been referred to as “empty magnification”. However such greater magnifications do still help aiming precision and target analysis by further reducing the field of view and useless clutter in the field of view.
Human Visual System Adaptation - the eye-brain visual system has adapted to its acuity limit by essentially filtering out (ignoring) any image detail below the acuity limit. When the optic quality is good enough to be diffraction limited and the magnification is high enough to make your magnified visual acuity limit better than the diffraction limit, two effects occur: increasing magnification adds no additional visible detail (although visible objects get bigger and occupy a larger portion of the field of view) and increasing magnification will show (for visible objects) more of the diffraction effects (such as fringing of edges due to optical interference) which are often perceived by inexperienced users as blurry objects or edges.
As with most tasks, with sufficient practice you can adapt and re-train your eye-brain visual system to correctly perceive high magnification diffraction limited images and better analyze the magnified small field of view with larger objects of interest (bullet holes) and less extraneous clutter (backer board).
For the March scope in question: Resolution = 0.037 MOA and Match Magnification = 26.9x
This thread is another example of problems with the perceived versus actual quality of high power scopes and the lack of well-defined terminology to explain the issue. The following is offered to aid the discussion.
Key Definition 1 – Resolution is the smallest detectable angular separation of two of the smallest objects of interest.
Eyesight Resolution Limitations – The normal or median human visual resolution limit is 1 MOA (minute of angle). This is also called normal visual acuity when use by your eye doctor. On the typical Snellen eye chart, the 20/20 line (20 foot line in USA) or 6/6 line (6 meters in the rest of the world) was designed to be readable with a visual resolution or acuity of 1 MOA. The other lines/characters are scaled accordingly (20/10 or 6/3 line is 0.5 MOA resolution and 20/40 or 6/12 line is 2 MOA resolution).
Scope Function – Telescopic sights (erecting refraction telescope) were developed as visual aids to overcome this limited visual resolution or acuity. The principal tool for resolution improvement is magnification. It is obvious that magnification increases the apparent size of objects. However and more importantly magnification helps to increases visual resolution of small but important details by both increasing their apparent size and reducing the available field of view.
Scope Resolution Limitations – A long historical record holds that diffraction defines the ultimate resolution limit of telescopes. Generally we can say that any aperture with a finite size will cause diffraction and hence its resolution will be limited. The finite aperture (objective lens) must cut off a part of the incoming plane wave front. This missing part distorts the otherwise perfect interference of the propagating waves in a certain way. For the current available quality scopes the Dawes limit currently gives the best (as supported by many observations) working value for the best resolution that can be reasonably expected in shooting applications.
Dawes's Resolution Limit [MOA] = 1.933 / Objective Diameter [mm].
Also = Smallest separation between features and minimum POA (point of aim) error (confusion circle)!
Key Definition 2 – Match Magnification means the Dawes Limit equals the magnified normal visual acuity of the human eye. At less magnification the scope resolution is limited by the user's visual acuity. Above match magnification the scope resolution is diffraction limited by the objective diameter to the Dawes Resolution Limit.
Match Magnification = Visual Acuity [MOA] / Dawes's Resolution Limit [MOA]
Magnifications greater than the match to Dawes Limit do not produce any more real resolution and has sometimes been referred to as “empty magnification”. However such greater magnifications do still help aiming precision and target analysis by further reducing the field of view and useless clutter in the field of view.
Human Visual System Adaptation - the eye-brain visual system has adapted to its acuity limit by essentially filtering out (ignoring) any image detail below the acuity limit. When the optic quality is good enough to be diffraction limited and the magnification is high enough to make your magnified visual acuity limit better than the diffraction limit, two effects occur: increasing magnification adds no additional visible detail (although visible objects get bigger and occupy a larger portion of the field of view) and increasing magnification will show (for visible objects) more of the diffraction effects (such as fringing of edges due to optical interference) which are often perceived by inexperienced users as blurry objects or edges.
As with most tasks, with sufficient practice you can adapt and re-train your eye-brain visual system to correctly perceive high magnification diffraction limited images and better analyze the magnified small field of view with larger objects of interest (bullet holes) and less extraneous clutter (backer board).
For the March scope in question: Resolution = 0.037 MOA and Match Magnification = 26.9x
Last edited:
Boyd Allen
Active member
Back in the 90s, with the assistance of a friend, I built a mount that held five scopes side by side, as close as operation room for their target turrets would allow. All of the mounts were adjusted to be aligned to a single distant point, and the mount would put the scopes at eye level with the observer setting at a sturdy portable table on which the mount and scopes was placed. Five different 36x scopes were mounted for comparison, and the whole shebang taken to a local sanctioned group match, where competitors were allowed to compare the scopes and adjust them any way that they wanted. My point in mentioning this is that perhaps another test of this sort might be interesting.
Eyes
To put what Fred Bohls and Andy Cross are saying in layman's terms. Eyes are like fingerprints. We all see the World through different lens(Eyes). Optically speaking, When looking through a Rifle scope/Binocular, Whats clear to some is not so clear to others.
Make sense?
Glenn
To put what Fred Bohls and Andy Cross are saying in layman's terms. Eyes are like fingerprints. We all see the World through different lens(Eyes). Optically speaking, When looking through a Rifle scope/Binocular, Whats clear to some is not so clear to others.
Make sense?
Glenn
Andy Cross
New member
Straight out of the text book
Yep can't debate any of that. It's straight out of the text books.
There are a couple of other things that I might point out. The air. It might look like a nice clear day but the air could be full of water, fine dust particles or smoke particles you can barely smell let alone see. Scopes that generally produce images that you normally consider sharp or clear etc might produce a less clear image today. The shooter immediately suspects the scope. The greater magnification you use the better the air has to be. Look at a target through a scope in a vacuum chamber and even a lousy scope starts looking good.
Another issue is the human brain. It interprets the electrical signal being sent by the optic nerve. For want of a better term if you have blurry software in the brain then no scope will look as if it's producing a sharp image.
Andy.
Yep can't debate any of that. It's straight out of the text books.
There are a couple of other things that I might point out. The air. It might look like a nice clear day but the air could be full of water, fine dust particles or smoke particles you can barely smell let alone see. Scopes that generally produce images that you normally consider sharp or clear etc might produce a less clear image today. The shooter immediately suspects the scope. The greater magnification you use the better the air has to be. Look at a target through a scope in a vacuum chamber and even a lousy scope starts looking good.
Another issue is the human brain. It interprets the electrical signal being sent by the optic nerve. For want of a better term if you have blurry software in the brain then no scope will look as if it's producing a sharp image.
Andy.
Butch Lambert
Active member
A very informative thread.
Fred Bohl
Retired Engineer
Boyd Allen
Starting in late 2006 a group of 5 of us target shooters all with experience with high power scopes began doing similar testing. The objective was to establish methods to do useful comparative testing. By the end the summer of 2009 we had looked through the 6 different scopes under very different conditions at 4 ranges. The significant conclusions were that we and others that tried our methods were biased in selection toward what we were use to using. Also, those not used to the testing method had a great deal of difficulty getting the eye position, eyepiece diopter setting and zero parallax adjustment optimal for the scope (again particularly for scopes the observers were not used to using). Another conclusion was that virtually all those that tried the test that never used a scope over 24 power (below match magnification) preferred the lowest power (36x) over any of the higher power scopes (40x, 42x, 45x, 50x or 60x) and the higher the power the lower they ranked the scopes and more difficulty they reported with the diopter and parallax adjustments.
At that point we shifted our strategy to using a digital imager in place of human observers and were making very good progress toward getting repeatable objective results by late 2011. Unfortunately, we lost one of our group and his two scopes in early 2012, another member and one scope in early 2012, and two of us have had cataract intraocular lens replacements since so the testing has all but stopped.
Starting in late 2006 a group of 5 of us target shooters all with experience with high power scopes began doing similar testing. The objective was to establish methods to do useful comparative testing. By the end the summer of 2009 we had looked through the 6 different scopes under very different conditions at 4 ranges. The significant conclusions were that we and others that tried our methods were biased in selection toward what we were use to using. Also, those not used to the testing method had a great deal of difficulty getting the eye position, eyepiece diopter setting and zero parallax adjustment optimal for the scope (again particularly for scopes the observers were not used to using). Another conclusion was that virtually all those that tried the test that never used a scope over 24 power (below match magnification) preferred the lowest power (36x) over any of the higher power scopes (40x, 42x, 45x, 50x or 60x) and the higher the power the lower they ranked the scopes and more difficulty they reported with the diopter and parallax adjustments.
At that point we shifted our strategy to using a digital imager in place of human observers and were making very good progress toward getting repeatable objective results by late 2011. Unfortunately, we lost one of our group and his two scopes in early 2012, another member and one scope in early 2012, and two of us have had cataract intraocular lens replacements since so the testing has all but stopped.
100% with Rex Reneau
In my opinion March EP 36-55 has the best optics in the benchrest line of scopes 40X 50X 60X. I still have one of the original 40X (excellent) and used a couple of 50X not as good opticaly and after trying one switched to the EP 36-55. I have now 5 of them on my benchrest rifles except one.
In my opinion March EP 36-55 has the best optics in the benchrest line of scopes 40X 50X 60X. I still have one of the original 40X (excellent) and used a couple of 50X not as good opticaly and after trying one switched to the EP 36-55. I have now 5 of them on my benchrest rifles except one.
jackie schmidt
New member
I had LASIK on my eyes about 4 months ago, which COMPLETLY changed the way I see the world, and my two 50x March's STILL look fuzz.
Butch Lambert
Active member
I had LASIK on my eyes about 4 months ago, which COMPLETLY changed the way I see the world, and my two 50x March's STILL look fuzz.
Well as noted, you must have a fuzzy brain.