Arken EP5 5-25x, Mini Review

Introduction

/u/Reloader300WM graciously loaned me his brand new Arken EP5 to play with while he waits on his rifle build.

Some of the pictures you will see came from yesterday, some from today. Both days were bright-overcast, and like yesterday, not the best conditions for stressing chromatic aberration, but a good day for testing how light is transmitted.

The Optika 6 is the reference optic being compared with because it is sitting on my desk unmounted to any rifle.

About Arken

Arken is one of the newcomer/startup optic makes that appeared pretty recently. I'm not exactly sure when, but seems like around 2019?

This generation of optics companies include other direct-to-consumer sale like Swampfox and Lucid. And like the other two, is very social media savvy, very publicity focused. Also, their main leaders all tilt left for some reason this was a joke you can read on r/longrange with an unsanitized link.

Arken Uh-oh

I'm not going to accuse Arken of any wrongdoing. It might have been bad actors, it might have been a big misunderstanding. Facts are loose and seemed to be shifting, and with layers of obscurity, I don't have a contract or program details beyond what was public.

I'm only stating the facts as I found them through my own research and digging, colored through the lens of someone self-protective of the community and with their best interests at heart.

On the r/longrange sub, Arken got into a bit of trouble last year because, besides a suspiciously smelly number of recommendations/reviews suddenly appearing, we found a user very deceptively posting an undisclosed instanced referral link to their optics sales page. One that would tie optic sales and visits to his account.

Immediately digging into what that was, it appeared that they had (or have) a promotional 'Gratisfaction Program', but within several days of the mod team publicly announcing their shadow-ban/forced mod review, references to the program vanished off the face of the web as if it were a ghost in the night.

Hm.

Even as of earlier this year, you could find references on their site to making sure community members had their accounts set up so they could get credit/acknowledgement for their referrals. Seems to allude to the previously more public program, even if it is tough to find it public now.

Side note, there is also a 'Gratisfaction' loyalty program app specifically for this type of marketing on a broader scale, but I don't know what connection there was between this an the referral link we saw posted.

What they are selling

Like their other upstart competitors, the Arken product line is made in China. Supposedly, they use Japanese glass elements.

But from who? Japan has several different glass houses offering a wide range of glass from alpha tier to budget tier.

Looking at their trading partners on importgenius, their 4 top partners are all chinese companies, the same ties with Vortex, Bushnell, Meade, and Athlon, but none with ties to japanese glass houses. That information doesn't seem to be available, probably because they are a small time scope maker so fall off the list of most important trade partners.

The formula is:

• Passable glass
• Fully or near fully featured optic (tracking turrets, zero stop, lock, illum, side focus, christmas tree, FFP
• "Lifetime warranty"
• Modest price

On the surface, this is a good plan. A little deeper... it has some problems.

1. The companies are startups. Lifetime doesn't mean much when they haven't been around but for a few years and could go away as easy as they came. Happens a lot in the optics world.

2. This market position is saturated and already dominated by big companies with good reputations, making the scraps a difficult thing to fight for.

3. Establishing a name amongst 100+ year old companies seems to push startups into less than ethical forms of promotion. Happens all over and leaves a bad taste in my mouth.

EP5

This is Arken's top of the line option.

• 5x erector
• "ELD" glass
• Big 56mm objective
• mil/mil
• Illuminated reticle with a center gap/dot and +
• Compact design - only 14"
• 34mm tube
• Zero stop (no locking)
• Comes with throw lever and inexpensive option to get a single piece mount
• 32 mil adjustment
• 10 mil turrets
• 39oz
• $530

Pretty impressive on paper, and certainly a good on-paper value. But let's dig into the details.

The Glass

A little primer on ED glass. ED/LD is a term to describe the property of the lens elements to keep light coherent.

When light bends, different frequencies bend different amounts. This is the rainbow/prism effect you've seen on Pink Floyd's Dark Side of the Moon. This is called Chromatic Aberration, and it causes 2 big effects. 1, it reduces apparent resolution by blurring/stretching the sharp/high contrast edges of light, and 2, it adds a moving false color on those edges.

ED glass could mean a few different things, but generally refers to achromatic doubles or apochromatic triplets being used on some optical interfaces.

The crown) and flint glass used in ED elements are more exotic and tuned together to produce the best coherency for the lens size/focal ratios.

And it adds significant cost. The biggest thing that separates a $1000, $2000, and a $4000 optic is now how well the turrets track or what features it has or durability. It is almost entirely how much ED glass is in it and the optical engineering of it.

Arken calls this "ELD" glass, but, that's a bit of a misconception. The whole scope is not "ELD". That would cost a fortune. There are many glass elements focusing the light down, moving it up/down, and expanding it back out again.

The Optika 6 2nd gen specifically states that:

Featuring 2 elements of ED glass in the objective, the 5-30x56 provides the ultimate in edge to edge clarity and resolution no matter the distance.

It also has significantly less CA than the EP5.

Look for the purple and green fringing in high contrast areas.

Here is the EP5 at:

• 25x
• 15x
• 10x

You can see how at high magnification, the CA can be pretty bad, and then at lower magnification on axis it is good, but off axis it is also pretty bad.

I believe the biggest contributor to this is the EP5 has a very large objective, very short length, and a pretty high 5x erector. That means it has to bend light a lot and do so over a very wide range of focal lengths. It can't keep up with the geometry difference and as such, you get chromatic aberration.

But if that was the case, you would see other optical artifacts too.

And you do.

Below about 15x, there is pretty severe pincushion/barrel distortion, which some people call a 'fisheye' effect. Basically it means that the image presented is no longer flat, it has a 'curve' that changes based on where your eye is relative to the center of the optic. It is a bit disorienting if you move your head around, and it tends to hurt my eyes. This effect gets worse towards the low end, so I would suspect they partially tuned this optic towards the high end.

Also, because of large objective and short package, it has a pretty tight eyebox at the top end, growing dramatically at the low end. And it also seems to have a pretty strong bright-spot in the center where the light-falloff happens dramatically, also probably because of its short packaging and trying to squeeze down quickly.

But, overall, it's not bad glass. It doesn't look cheap necessarily, and is pretty good for $500. But people claiming it is Razor or other popular LOW optic quality or something, well, it isn't.

The other thing I'm not too crazy about is the illum. At max power on daylight, the illum has a reticle shadow or bloom that moves with your head relative to the optic center. Here is a picture of that. It might go away at lower illum levels, but for a daylight contrast level, it is very obvious and present.

I think my favorite part of this optic is the reticle. They didn't deviate dramatically, maybe even looked a little too closely at Vortex's EBR-2D homework, but is otherwise a reasonable design. Precise center, clean uncomplicated measurements on the crosshair, clean dots with numbers on the outside, and nice eyeguides for low magnification. Great job on that one.

Overall, I would say the Optika 6 I reviewed and the Bushnell Match Pro ED both have better glass (even significantly so), similarly great reticles, but for $150-300 more money.

edit sun peaked out so I got some more shots of the CA, 4 total, one more on axis, one more off axis of each of the EP5 and Optika6 at 25x:

• EP5 Image 1 and Image 2
• Optika 6 Image 1 and Image 2

Sharp or in focus, on or off axis, the Optika 6 slays the EP5 in CA performance.

The Turrets/Controls

Everything was laid out really well. The turret indicators were good, they worked right, had the right information in the right spots. High contrast, bold fonts, big numbers/letters. I really liked all of that.

The turrets are very tactile and audible and are slightly underdamped, much like the Optika 6 turrets. I would have preferred a bit more damping.

Turrets, side focus, and magnification all turn easily, which is good, much better than the stiff controls on the PST II and some others.

The zero stop/turret cap design is interesting. It has a set screw that you can adjust and lock externally on the turret in addition to the typical 3 screw design used for keeping the cap attached to the actual adjustment/erector.

Tracking seemed fine. I didn't notice any significant measurement error or tracking error over ~20 MIL of travel.

Turrets/touch surfaces are nice. The knurling is grippy, chunky, without being sharp. Kudos on that.

My only complaint with the turrets/controls is that the turrets have some snap-back or let-off, a little 'chug' sound and movement after it has dropped into its measurement notch.

If you watch the video carefully, you can actually see and hear this little 'chuck, chuck' sound after I relax my hand.

Final Thoughts

This is a solid feeling optic. The weight helps, the turrets and controls lock up pretty good. The finish is nice. The glass is decent for the price.

I get it. I get why they have a following. If you choose to buy one, I think it will be a decent optic for you.

But I am probably not going to be their champion. The company is still problematic to me and I don't think it is unique in this space and at the price point it is. I think it is very close to some optics that have a good track record depending on what you're looking for.

submitted by /u/Trollygag
[link] [comments]