May 212016

Review of the Minox ZP8 1-8x24mm Illuminated Optic

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Les (Jim) Fischer

May 21, 2016

Table of Contents:
– Background
– Unboxing and Physical Description
– Reticle
– Comparative Optical Evaluation
– Mechanical Testing and Turret Discussion:
– Summary and Conclusion
– Close Quarters Speed Testing and Illumination
– Testing Methodology:  Adjustments, Reticle Size, Reticle Cant
– Testing Methodology:  Comparative Optical Evaluation
– Testing Methodology:  Close Quarters Speed


If any scope was a white whale to any writer, this is probably the scope and I am probably the disagreeable old salt. You see, the story of 1-8x scopes doesn’t start with the Leupold CQBSS, the first actually released, but rather with the S&B short dot 1-8x that probably never will be, in original 1fp reticle 2fp dot configuration.

I first heard of the S&B short dot 1-8x in 2010 when it debuted at SHOT Show. At that same show, Premier Reticles debuted a 1.1-8x. That second scope came about through a partnership between Premier Reticles and Optronika, a company formed when an engineering team left S&B to strike out on their own in 2008. At that time it looked to be a compelling race both in technical terms, as it was a race to make what I considered the first all-in-one daytime optic, and in human terms, as former teammates competing against each other always introduces another dynamic.

As often happens though, history would not become what people expected. S&B would kick around their design for years and eventually decide that the costs of production in original first focal plane with projected red dot configuration was too cost prohibitive. They would instead split the concept and produce two separate models disappointing many folks who were desirous of a first focal plane scope with a projected dot. Premier would scrap the 1.1-8x design and debut a 1-8x only to never produce either on a large scale (I believe a few 1.1-8x’s were sold to individuals who preordered and put money down). Premier Reticles would eventually be bought by an industry veteran, take up a more northern address, and become Tangent Theta. I would go on to review three 1-8x designs produced by other makers, but could not forget about those original two that seemed destined never to exist.

This summer, when watching Ilya’s SHOT 2015 notes, I learned that the Minox 1-8x which I had caught wind of was a product of the Optronika folks (now working with Minox) and actually existed. I would later find out that this Minox 1-8x was actually the refined descendant of the Premier 1-8x design that Oprtronika had retained the rights to. I was quite pleased that some product of this ill-fated contest had eventually born fruit and I obtained one for testing. Let us see if it has been worth the wait.

Unboxing and Physical Description:

Most of the scopes that I have reviewed in the past arrive on my doorstep new in wrapping. The exceptions to this have been three late gen prototypes, three designated test scopes, and the personal scope of one of Leupold’s marketing guys. Each exception to the typical shrink-wrapped shiny has tended to foster further exceptions. I have had prototypes without final lens coatings, with different than final markings, with perhaps more careful than normal assembly, and even custom shop produced scopes that should not have met the QC standards of the run of the mill. I have had designated test scopes that came with plastic insert lined rings to stay minty fresh and some that looked like they had already seen battle.

This particular exceptional scope came dressed only in unmarked Tenebraex caps in a brown shipping box with a separate package of Warne quick detach rings that I presume are a result of my request to provide rings with all test scopes as I otherwise frequently run short when several scopes are simultaneously on hand. I would later find, as is relatively common in testing, that this test scope was an early production model and a few changes have been made since then that the reader will find informative. As a result of customer feedback, maximum illumination brightness has also been increased. Additionally, the knurling on the turrets has been improved and their clicks have been made more tactile. Those buying the scope today will receive a product with these changes packaged with Tenebraex caps, a manual, spare battery, lens cloth, and hex wrench. I was able to download the manual online. It is a pleasingly technically detailed affair entirely devoid of marketing attempts to get me to buy the scope I have obviously already bought since I have the manual. The manual even goes so far as to chart the maximum possible parallax deviation for ranges from 0-1000 meters. I would characterize it as being in the European style, which is to say that it contains actual information where an American manual would have warnings and/or advertisements.

Minox ZP-8 1-8x with included Tenebraex flip caps
Minox ZP-8 1-8x with included Tenebraex flip caps

As for the optic itself, the ZP-8 1-8x24mm bears a great deal of resemblance the stillborn Premier 1-8x design that is it’s forbearer. The location of the saddle towards the front, illumination turret design, and angular eyepiece with locking diopter are all familiar. The greatest point of divergence from the old specification is the turret design. Both designs have 10 mil .1 mil per click single turn turrets that I have been informed are in response to a particular military requirement. The Premier version had the additional feature of a semi-toolless zero and zero stop reset whereas the Minox features a locking function that holds the turret at zero while engaged. Ergonomically, I like the built-in low profile cattail, but think that the turrets and illumination control are a bit large for their feature content. The illumination control is the size of others I have encountered that also include a parallax and the turrets are similar in size to turrets including second rotations and pop-up indicators for those additional rotations. Also, though the low profile cattail is a nice grip, it is rather alone in this pursuit. Though the power ring is quite large, it is otherwise almost entirely smooth where I find myself wanting for some grip. The positioning of the cattail is good, having about a 220 degree throw which starts exactly where the thumb of your right hand will be when you change the power from 8x to 1x with an overhand grip. However, the 220 or so degrees will probably be further than you typically rotate with one grip and when you re-grasp, things will line up less advantageously leaving you to wonder why, with all that potential space for it, there is no more grip. The appearance of this arrangement is nice but ultimately I prefer the entire power ring to be grippy.


Designing the reticle for a 1-8x ffp scope is a significant challenge since at 8x that reticle will appear eight times the size that it appears at 1x and only 1/8th of it will be visible. It is also a challenge because with an 8x erector system between the reticle and the user, you can expect that the reticle would have to be etched very finely indeed to appear at all crisp to the user. Etching this fine is certainly possible, as illustrated by the Leupold CQBSS, though I have seen other 1-8x scopes that had reticles with a very thick “hairy caterpillar” appearance so I expect such etching is neither common nor inexpensive. The review ZP8 I have has the MR10 reticle and it does not have a hairy appearance, but is still rather thick looking at 8x and lacks much in the way of design. It is basically a mil hash with dot center crossed with a German #4. There are only two line widths:   the hash, dot, and top post are one line width and the other three posts are thicker. Divisions are in full mils with an extra wide line for the 5th. Though it is not a very creative design, in testing I found the MR10 to not interfere with the speed of the optic as the posts were thin enough at 1x not to be distracting and at that point you are pretty much just going on the projected red dot, which is good. At high power, the lines were a bit thick for the kind of precision I like to have, but from a practical standpoint were fine. I just really like the experience of shooting with fine lines even though the actual difference in my performance is small.

In addition to the MR10 reticle I tested, the ZP8 also comes in an A8-D reticle and an MR10+ reticle. The A8-D is basically a duplex design. The MR10+ is the MR10 I had with the addition of a limited 1mil grid below the primary aiming point for the same purpose as a Christmas tree and rapid ranging feature in the 9:00 quadrant. I like both of these concepts, especially as its 1mil grid is very sparse. The rapid ranging feature is, like most such features, dependent on the user’s understanding of the markings and what they stand for. The markings, in this case, are based on 1 meter vertical or .5 meter horizontal target dimensions. My biggest criticisms of this particular feature in this particular design are as follows. First, it is one of the more difficult to intuit arrangements I have seen and the user may forget how to use it between the time the manual is read or training administered and its actual use. Second, its arrangement does not allow the easy off-label calculations that it would if all markings were paired with their exact halves such as 300 and 600 meters or divided in half as is sometimes the case on other designs. Finally, in my past experience, 1 meter has not proven to be a large enough stadia to easily range, though with 8x max magnification, the Minox may somewhat mitigate this. What I liked most about this rapid ranging feature was that, in addition to existing (I like rapid ranging features), it was very cleverly and efficiently laid out in terms of real estate used and therefore obscured very little. In addition to the additional ranging and distance compensation features over the MR10, the MR10+ also has double the thickness outer posts on the reticle. I was sad to hear of this as thick posts in all forms have consistently proven to be a speed killer in my close quarters testing despite the common belief that they will increase speed by being more noticeable at low power. Close quarters speed seems to have more to do with seeing the target than the aim point. Those who have become proficient at skeet shooting or sporting clays probably expect this, though most will find it counterintuitive. This leaves me with mixed expectations for the MR10+. It is a significant step up from the MR10 in terms of its ranging and distance compensation features, but I expect it may be slower due to the thicker outer posts.

MR10 reticle in the Minox ZP-8 1-8x scope as viewed through the scope at 8x during mechanical testing
MR10 reticle in the Minox ZP-8 1-8x scope as viewed through the scope at 8x during mechanical testing

Comparative Optical Evaluation:

It is a shame that I did not still possess any of the 1-8x scopes from my review a few years ago at the time I tested this optic. That being said, I did still have quite a few optics to compare it to. At the time of testing, I had 1-6x designs from Optisan and GRSC / Norden Performance, a 1/4x Elcan Specter DR, and a few high powered designs in the Leupold MK 6 3-18x and Zeiss Conquest 4.5-14x. While in no cases was this an apples to apples comparison, it was quite sufficient to give me a sense of where the ZP8 fits in the grand scheme of things as relates to optical performance.

My initial impressions as I started testing the ZP8 were not good. The eyebox at maximum power is quite critical, even for a 1-8x. This makes testing more difficult and less comfortable. You will note that the through-the-lens photo in the reticle section appears just a little off axis. It took a great deal of effort to get a picture that good and it is still well below my average quality for such photos. Adding to the difficulty of good eye position was an issue with stray light. Usually, the blacker the blacks and deeper the greens, the better scope will prove to be in most optical respects. Scopes that have a bleached out look suffer from stray light from internal reflections. Most scopes that are high on the stray light issues suffer from just about every other issue as well. Since these are amongst the first things I notice in an optic, it was not looking good for the ZP8.

With this sense of foreboding, I trudged on testing each of the many optical issues that I usually look for. I was surprised when the Minox showed no noticeable chromatic aberration and further surprised when the resolution proved to be good, better even than the Elcan. The field of view also seemed sufficient. It was not even the smallest in my group despite the much more difficult 1-8x design. The color rendition appeared to be fairly even and it rendered blue as blue instead of the common rendition as black. The barrel and pincushion distortions were also not of large magnitude as is common with many aggressive optical designs.

So, in the end, the ZP8 did not bomb out on the optical performance, though it did have a rocky start. With the stray light issue, I would certainly recommend a sunshade or ARD and, because of the small eyebox, it is not very comfortable to use at max power, but it does resolve very well and does not have any other major optical issues. Without trying to run the risk of comparing it directly to any of the 1-8x designs I have reviewed in the past, I would venture to say its overall performance is on the lower side of the middle of 1-8x designs. My initial impression was misleading regarding optical performance just as it would later be misleading in close quarters performance.

The comparison lineup from left to right- Leupold MK6 3-18x44, Zeiss Conquest 4.5-14x44, Optisan CX6 1-6x, Norden Performance GRSC CRS 1-6x, and Minox ZP8 1-8x, *Elcan Specter DR 1/4x  not pictured*
The comparison lineup from left to right- Leupold MK6 3-18×44, Zeiss Conquest 4.5-14×44, Optisan CX6 1-6x, Norden Performance GRSC CRS 1-6x, and Minox ZP8 1-8x, *Elcan Specter DR 1/4x not pictured*

Mechanical Testing and Turret Discussion:

The practical distinction of most 1-8x designs from 1-6x designs is usually that the former is equipped for use at long enough range for significant drop and drift compensation. A 1-6x design is typically just a 1-4x close quarters scope with a little more magnification, perhaps for observation or target identification. Most 1-8x designs are actually precision rifle scopes with large turrets, zero stops, and 10mils per turn precise click adjustments. The ZP8 does feature fairly large turrets with .1mil clicks, a zero stop, and a push-down pull-up lock at zero only. The only surprising feature of the elevation knob is the single turn limitation. I found this strange as the internal travel is far more than 10 mils and was later informed that the limitation is the result of a particular set of military requirements. The windage is also limited to half a turn, 5 mils each way though this is common among precision scopes. In the case of both adjustment knobs, zero is reset using three set screws, a common (though inelegant) solution. The feel of the adjustments is acceptable. They move with about average force with clicks that are lightly tactile though barely audible. I am not a real stickler on adjustment feel so I will call them fine. I have been told that the turret feel has been significantly improved since the production of the test scope I used so I do not anticipate that a prospective buyer would be displeased even if a bit more picky about turret feel than me.

In testing, I found the adjustment magnitude small by .2mils at 10mils, measuring 9.8mil traveled at 10mil on the scale. Windage out to 4mils appeared fine left and .1mil small right. I expect that the actual windage deviation is the same magnitude elevation, however windage deviation is much more difficult to test in practice as the target and elevation knobs have smaller travel ranges and, more importantly, it is difficult to square the target precisely to the shooter. Both adjustments returned to zero properly. My testing further found accurate reticle dimensions, no zero shift with power change, and no measurable reticle cant. In order to further test the elevation travel, I reset the zero stop at 10mils to measure the travel from 10-20 mils from optical center. The same .2mil @ 10 mil deviation was noted. Also noted was a significant diminution of optical clarity becoming very noticeable around 15mils from optical center. All scopes deteriorate optically as they diverge from optical center, so this was not abnormal or alarming in any way.

Overall, the magnitude of adjustment deviation in the ZP8 is greater than the average I have found in testing high powered precision scopes, though it is by no means the greatest. It would be very interesting to have tested all the other 1-8x scopes in this manner when I reviewed them a few years back, but I did not yet have the capability at that time. For those interested, this 2% deviation comes out to a little less 20cm at 800 meters for a .308 cartridge though, since the deviation is linear, it could easily be eliminated in practice by adjusting for it during the process of creating the ballistic table. In such a scenario, no ill effects result from the deviation in adjustment magnitude.

Minox ZP8 1-8x adjustments
Minox ZP8 1-8x adjustments

Close Quarters Speed Testing and Illumination

My initial expectation for the Minox in close quarter testing was that it would be rather slow. This expectation was based on the conventional crosshair type reticle design, and illumination that initially did not seem bright enough to me.

Though the illumination of the Minox is based on the new diffraction grating technology you may have heard me talk about in my SHOT 2014 blog, a technology capable of being obviously daytime bright, Minox initially did not provide a setting which had this obvious daytime pop. I thought it would not be enough and, for the most illumination sensitive of our testers, it wasn’t. However, for all other testers the scope functioned as daytime bright even when testing was in the direction of the sun. My conclusion was that the illumination was bright enough to get most users’ attention in daytime use and my initial impression was therefore incorrect, though common. In the end, it was a common enough impression that Minox has since decided to include brighter illumination settings anyway, rendering arguments on the point moot. I should mention that this daytime bright dot is in addition to a non-daytime bright illumination of the reticle scheme and that which illumination is present automatically switches with the power ring at about 2x. This is a very seamless and intuitive way to accomplish the switch.

Similar to my mistaken expectations regarding the illumination sufficiency, I proved to be too hasty on the reticle judgment as, at 1x, it was so fine as to not be a distraction to close quarters use. Furthermore, at low power the scope did not have any of the issues with stray light it had exhibited at high power, so do not expect any whiteout lens flare from difficult sun angles. Only minimal image distortion was present (there is always some distortion in any scope), allowing for good left/right eye merging in both eyes open use. Field of view was middle of the road, which is pretty good when you’re the only 1-8x scope in a lineup that includes the massive FOV of the unconventional Elcan Specter DR design. Eyebox at 1x was in line with what I am used to from 1-4x and 1-6x designs and therefore better than 1-8x designs I have tested in the past.

On balance, the Minox averaged on the faster side of a test group which was notably skewed toward scopes that have, in the past, been on the better sides of previous close quarters testing. I believe all the scopes used as references against the Minox in this close quarters testing are actually in the top 25% of all scopes I have tested in that regard. Given that most 1-8x scopes I have tested in the past have not been in the top 50% of scopes tested, the Minox, being better than average for this difficult lineup did very well overall indeed and I expect will do even better with the brighter illumination setting.

The Minox ZP8 1-8x during close quarters testing
The Minox ZP8 1-8x during close quarters testing

Summary and Conclusion:

It is difficult to write this conclusion as it is always hard to be objective when you are emotionally involved. Having seen prototypes for years along the way and following the twisting and turning of who works for whom and is producing what, I really wanted something that was probably entirely unrealistic. I wanted a 1-8x that was the size and weight of a 1-6x and had the mechanical performance of a sniper scope, all with uncompromising optical performance. This is wholly unrealistic and none of the 1-8x designs that I have tested in the past have come close to achieving that. In practice, the Minox represents a 1-8x of similar size and weight to most other scopes in this category. I believe it is faster in close quarters testing all of those and I expect that if it were stacked up to them optically, it would be average. In short, I do not feel that any of the 1-8x designs on the market has yet achieved the goals of the one rifle one optic dream. However, this is one of the top 1-8x scopes, performing particularly well in close quarters testing and also having a good feature set for use at range.

Here is Your Pro and Con Breakdown:

Excellent close quarters performance, probably the best 1-8x in this respect
High resolution, low distortion, and low chromatic aberration
Diffraction grating based illumination system that will be daytime bright on new scopes
Illumination system automatically switches from dot to whole reticle with the power ring
.1mil per click, 10 mil total locking click adjustments
Reticle was spot on accurate and had no measurable cant
Included Tenebraex caps and a good warranty make for nice extras

Weight, size, and cost are in line with other 1-8x designs – high
Small eyebox at high power makes it uncomfortable to be behind
I can’t find myself loving any of the reticle designs
Illumination on the first production run may not be seen as daytime bright by some users
Haze from stray light makes the image less dynamic at high powers > about 6x
Adjustment accuracy deviation of 2% was high for precision rifle scopes

Testing Methodology:  Adjustments, Reticle Size, Reticle Cant

When testing scope adjustments, I use the adjustable V-block on the right of the test rig to first center the erector. About .2 or so mil of deviation is allowed from center in the erector, as it is difficult to do better than this because the adjustable V-block has some play in it. I next set the zero stop (on scopes with such a feature) to this centered erector and attach the optic to the rail on the left side of the rig.

Test rig in use testing the adjustments of the Vortex Razor HD II 4.5-27x56
Test rig in use testing the adjustments of the Vortex Razor HD II 4.5-27×56

The three fine threaded 7/16″ bolts on the rig allow the scope to be aimed precisely at a Horus CATS 280F target 100 yds down range as measured by a quality fiberglass tape measure. The reticle is aimed such that its centerline is perfectly aligned with the centerline of the target and it is vertically centered on the 0 mil elevation line.

Horus CATS 280F target inverted and viewed though the Leupold Mark 6 3-18x44
Horus CATS 280F target inverted and viewed though the Leupold Mark 6 3-18×44

The CATS target is graduated in both mils and true MOA and calibrated for 100 yards. The target is mounted upside down on a target backer designed specifically for this purpose as the target was designed to be fired at rather than being used in conjunction with a stationary scope. Since up for bullet impact means down for reticle movement on the target, the inversion is necessary. With the three bolts tightened on the test rig head, the deflection of the rig is about .1 mil under the force required to move adjustments. The rig immediately returns to zero when the force is removed. It is a very solid, very precise, test platform. Each click of movement in the scope adjustments moves the reticle on the target and this can observed by the tester as it actually happens during the test. It’s quite a lot of fun if you are a bit of a nerd like I am. After properly setting the parallax and diopter, I move the elevation adjustment though the range from erector center until it stops, making note every 5 mils of adjustment dialed of any deviation in the position of the reticle on the target relative to where it should be and also making note of the total travel and any excess travel in the elevation knob after the reticle stops moving but before the knob stops. I then reverse the process and go back down to zero. This is done several times to verify consistency with any notes taken of changes. After testing the elevation adjustments in this way, the windage adjustments are tested out to 4 mils each way in similar fashion using the same target and basically the same method. After concluding the testing of adjustments I also test the reticle size calibration. This is done quite easily on this same target by comparing the reticle markings to those on the target. Lastly, this test target has a reticle cant testing function (basically a giant protractor) that I utilize to test reticle cant. This involves the elevation test as described above, a note of how far the reticle deviates horizontally from center during this test, and a little math to calculate the angle described by that amount of horizontal deviation over that degree of vertical travel.

Testing a single scope of a given model, from a given manufacturer, which is really all that is feasible, is not meant to be indicative of all scopes from that maker. Accuracy of adjustments, reticle size, and cant will differ from scope to scope. After testing a number of scopes, I have a few theories as to why. As designed on paper, I doubt that any decent scope has flaws resulting in inaccurate clicks in the center of the adjustment range. Similarly, I expect few scopes are designed with inaccurate reticle sizes (and I don’t even know how you would go about designing a canted reticle as the reticle is etched on a round piece of glass and cant simply results from it being rotated incorrectly when positioned). However, ideal designs aside, during scope assembly the lenses are positioned by hand and will be off by this much or that much. This deviation in lens position from design spec can cause the reticle size or adjustment magnitude to be incorrect and, I believe, is the reason for these problems in most scopes. Every scope maker is going to have a maximum acceptable amount of deviation from spec that is acceptable to them and I very much doubt they would be willing to tell you what this number is, or better yet, what the standard of deviation is. The tighter the tolerance, the better from the standpoint of the buyer, but also the longer average time it will take to assemble a scope and, therefore, the higher the cost. Assembly time is a major cost in scope manufacture. It is actually the reason that those S&B 1-8x short dots I lusted over never made it to market. I can tell you from seeing the prototype that they were a good design, but they were also a ridiculously tight tolerance design. In the end, the average time of assembly was such that it did not make sense to bring them to market as they would cost more than it was believed the market would bear. This is a particular concern for scopes that have high magnification ratios and also those that are short in length. Both of these design attributes tend to make assembly very touchy in the tolerance department. This should make you, the buyer, particularly careful to test scopes purchased that have these desirable attributes as manufacturers will face greater pressure on this type of scope to allow looser standards. If you test yours and find it lacking, I expect that you will not have too much difficulty in convincing a maker with a reputation for good customer service to remedy it:  squeaky wheel gets the oil and all that.

Before I leave adjustments, reticle size, and reticle cant, I will give you some general trends I have noticed so far. The average adjustment deviation seems to vary on many models with distance from optical center. This is a good endorsement for a 20 MOA base, as it will keep you closer to center. The average deviation for a scope’s elevation seems to be about .1% at 10 mils. Reticle size deviation is sometimes found to vary with adjustments so that both the reticle and adjustments are off in the same way and with similar magnitude. This makes them agree with each other when it comes to follow up shots. I expect this is caused by the error in lens position affecting both the same. In scopes that have had a reticle with error it has been of this variety, but less scopes have this issue than have adjustments that are off. Reticle size deviation does not appear to vary as you move from erector center. The mean amount of reticle error is about .05%. Reticle cant mean is about .05 degrees. Reticle cant, it should be noted, Affects the shooter as a function of calculated drop and can easily get lost in the windage read. As an example, a 1 degree cant equates to about 21cm at 1000 meters with a 168gr .308 load that drops 12.1 mils at that distance. That is a lot of drop and a windage misread of 1 mph is of substantially greater magnitude (more than 34 cm) than our example reticle cant-induced error. This type of calculation should be kept in mind when examining all mechanical and optical deviations in a given scope:  a deviation is really only important if it is of a magnitude similar to the deviations expected to be introduced by they shooter, conditions, rifle, and ammunition.

Testing Methodology:  Comparative Optical Evaluation

The goal of my optical performance evaluation is NOT to attempt to establish some sort of objective ranking system. There are a number of reasons for this. Firstly, it is notoriously difficult to measure optics in an objective and quantifiable way. Tools, such as MTF plots, have been devised for that purpose primarily by the photography business. Use of such tools for measuring rifle scopes is complicated by the fact that scopes do not have any image recording function and therefore a camera must be used in conjunction with the scope. Those who have taken through-the-scope pictures will understand the image to image variance in quality and the ridiculousness of attempting to determine quality of the scope via images so obtained.  Beyond the difficulty of applying objective and quantifiable tools from the photography industry to rifle scopes, additional difficulties are encountered in the duplication of repeatable and meaningful test conditions. Rifle scopes are designed to be used primarily outside, in natural lighting, and over substantial distances. Natural lighting conditions are not amenable to repeat performances. This is especially true if you live in central Ohio, as I do. Without repeatable conditions, analysis tools have no value, as the conditions are a primary factor in the performance of the optic. Lastly, the analysis of any data gathered, even if such meaningful data were gathered, would not be without additional difficulties. It is not immediately obvious which aspects of optical performance, such as resolution, color rendition, contrast, curvature of field, distortion, and chromatic aberration, should be considered of greater or lesser importance. For such analysis to have great value, not only would a ranking of optical aspects be in order, but a compelling and decisive formula would have to be devised to quantitatively weigh the relative merits of the different aspects. Suffice it to say, I have neither the desire, nor the resources, to embark on such a multi-million dollar project and, further, I expect it would be a failure anyway as, in the end, no agreement will be reached on the relative weights of different factors in analysis.

The goal of my optical performance evaluation is instead to help the reader get a sense of the personality of a particular optic. Much of the testing documents the particular impressions each optic makes on the tester. An example of this might be a scope with a particularly poor eyebox behind which the user notices he just can’t seem to get to a point where the whole image is clear. Likewise, a scope might jump out to the tester as having a very bad chromatic aberration problem that makes it difficult to see things clearly as everything is fringed with odd colors. Often these personality quirks mean more to the users experience than any particular magnitude of resolution number would. My testing seeks to document the experience of using a particular scope in such a way that the reader will form an impression similar to that of the tester with regard to like or dislike and the reasons for that.

The central technique utilized for this testing is comparative observation. One of the test heads designed for my testing apparatus consists of five V-blocks of which four are adjustable. This allows each of the four scopes on the adjustable blocks to be aimed such that they are collinear with the fifth. For the majority of the testing each scope is then set to the same power (the highest power shared by all as a rule). Though power numbers are by no means accurately marked, an approximation will be obtained. Each scope will have the diopter individually adjusted by the tester. A variety of targets, including both natural backdrops and optical test targets, will be observed through the plurality of optics with the parallax being adjusted for each optic at each target. A variety of lighting conditions over a variety of days will be utilized. The observations through all of these sessions will be combined in the way that the tester best believes conveys his opinion of the optics performance and explains the reasons why.

A variety of optical test targets viewed through the Leupold Mark 6 3-18x44
A variety of optical test targets viewed through the Leupold Mark 6 3-18×44

Testing Methodology:  Close Quarters Speed

As with the assessment of optical performance, the assessment of close quarters speed is a subjective process similarly involving a lineup of comparison scopes. Each scope is affixed in turn to an airsoft AR15 and used to engage an array of targets arranged in a 180 degree field of fire from the shooter. The use of a quality airsoft rifle as the test vehicle both reduces cost and virtually eliminates safety concerns relating to such a wide field of fire. Central to this testing is the use of multiple shooters and multiple firing scenarios. These firing scenarios involve movement on the part of the shooter, mounting and unmounting of the rifle, target to target transitions, and firing from the non-dominant side. Scopes are assessed with and without their illumination active. The panel of shooters has proven invaluable in this testing as different shooters have proven to have different tolerances to differing aspects of optical comprises. For instance, I am relatively insensitive to poor or absent illumination but very sensitive to barrel and pincushion distortion of the image. One of my other testers is relatively insensitive to this distortion but very sensitive to bright illumination. I also have a tester who seems very sensitive to reticle design and another for whom eyebox seems quite crucial. Gathering together the rankings and comments of all these shooters on a test lineup of scopes after a few hours of swapping them on and off the test rifle provides enough data to write something intelligent on the general performance of a particular optic relative to its peers as well as some specific information about which aspects of design that scope excelled in or was deficient in.

An over-the-shoulder view of close quarters speed testing in progress
An over-the-shoulder view of close quarters speed testing in progress