Rifle Scopes ZCO ZC420 v Kahles K318i v Schmidt Ultra Shorts v Minox ZP5
- Thread starter Glassaholic
- Start date
If some have the yellow halo and some do not, really makes me wonder what might be causing it???
In-person or in images only ?
The yellow cast can come from the camera taking the picture
The yellow cast can come from the camera taking the picture
The yellow halo is seen in person (I could not replicate it using my DSLR), I have seen some other through the scope pics of the ZCO where it seems more prominent so it might be induced to the camera through different environmental factors.
Wonder if the yellow ring is seen in newer or just older models as well. If its just older could be a slight manufacturing or design issue that has been corrected, or could be a less than spec lot of coatings. Would be interesting to find out the actual reason or it.
Calling @koshkin
The ZC420 we had was purchased after yours, so doesn't appear to be an issue of early models having been corrected.
Well things did not go right and the deal for the ZC420 fell through so I will not have another to test out the yellow halo.
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Deleted member 121493
Guest
I have a new 420 it also has the halo. Doesn’t bother meat all! The scope is just fantastic! Ultra clear, depth of field beats any Pm2 I have had. Just a great optic.
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Deleted member 121493
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Came back home and looked through my Swarovski atx95 and I see the exact same thing. Thin yellow halo along the edge of the visual field. MY conclusion: nothing wrong with the scope! Love it!
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You're find that even with the tangent theta. Only it's not yellow its purple/blue. I think some eyes are more sensitive to one colour or the other.
A ton of scopes have that halo. If it is contained to the outer edge, it is not an issue. It is largely a consequence of the angle stack up at the edges of the FOV. You are looking at a curved lens surface from at a more oblique angle there.
ILya
ILya
They are really looking for something to complain about.
Most focus on stuff that has very little bearing on their actual shooting with this stuff, they take X number of scopes all within $500 of each other and then endless pick out the most obscure thing to point at in order to justify why they picked THAT ONE over the others.
It's some weird fetish, touch them all and see which one makes the hair on their arms stand up,
Most focus on stuff that has very little bearing on their actual shooting with this stuff, they take X number of scopes all within $500 of each other and then endless pick out the most obscure thing to point at in order to justify why they picked THAT ONE over the others.
It's some weird fetish, touch them all and see which one makes the hair on their arms stand up,
Appreciate the explanation ILya, it was a strange phenomenon that I had not seen in other scopes before, didn't affect IQ at all but just an observation during certain conditions (mostly bright sun), the Minox ZP5 and two Schmidt Ultra Shorts did not exhibit this behavior during testing. I wondered if the enormous sight picture had any part to play, but the March 5-42x56 also has a similarly large sight picture and I have not yet observed the halo.
Probably more to do with the curvature of the lenses at the edges like Ilya explained. I dont even notice it when I shoot it's a very thin line on the other edge. I see it in every scope even the ZP5 only different is colour. Some are yellow/orange some are blue/purple. Mabe different angles different spectures (talking outa my ass here). Regardless I dont think it's an issue at all.
Chromatic aberration is due to the misalignment of the color wavelengths, I wonder if the edge curvature has a similar phenomenon which would explain the yellow/orange and blue/purple you mention.
You are missing a key element in this, especially when you are "comparing" what you see in one optic vs the others.
One it's because they choke the FOV to hide the edges. There is a Field Stop in place that is designed to cheat the system.
The Zco has a bigger FOV, and is a short focal length scope, so you see the ring because the smaller field stop reflects from the glass. look at the two images above the Zco has a wider FOV you can see the target to the right and the Kahles you cannot.
The longer the scope the less this should be an issue, but at the same time, this is field stop action is why scopes like the S&B Tunnel.
it's all trade offs, not seeing means they probably choked off your FOV. Opening up that FOV in a short optic you'll likely see it.
it has nothing to do with CA
One it's because they choke the FOV to hide the edges. There is a Field Stop in place that is designed to cheat the system.
The Zco has a bigger FOV, and is a short focal length scope, so you see the ring because the smaller field stop reflects from the glass. look at the two images above the Zco has a wider FOV you can see the target to the right and the Kahles you cannot.
The longer the scope the less this should be an issue, but at the same time, this is field stop action is why scopes like the S&B Tunnel.
it's all trade offs, not seeing means they probably choked off your FOV. Opening up that FOV in a short optic you'll likely see it.
it has nothing to do with CA
Thank you Frank, I have a suspicion that Kahles had some issues with their optical design which necessitated inhibiting the FOV in their new K525i/K318i series. The ZCO is brilliant edge to edge and while their FOV is more narrow than say the Tangent/ZP5 scopes, the scope is quite a bit shorter which as you mention has a shorter focal length and when you have a shorter focal length you have other optical challenges to address, some manufacturers choose to compromise in order to keep costs down or for other reasons. The ZCO ZC4-20, IMO, still reigns as the best engineered Ultra Short design available which rivals many "longer" scopes.
This is why it's not so cut and dry, black and white,
You compare a long scope like a Minox to a Short Scope you are gonna see things differently if you start checking around the edges.
There is always trade-off on the why a manufacturer did something, you can't always do an apple to apple comparison to the Nth degree, at some point, you start crossing into foreign territory.
One of the reasons why I want to establish criteria to highlight the more important aspects of the scope, things that would be more important to the user. This why when say asks, hey I see a yellow ring around the edge, we can stop it right there and say, Ya, just a wide-open FOV and that is a reflection off the Field Stop and not an issue. End of story, no debate.
You compare a long scope like a Minox to a Short Scope you are gonna see things differently if you start checking around the edges.
There is always trade-off on the why a manufacturer did something, you can't always do an apple to apple comparison to the Nth degree, at some point, you start crossing into foreign territory.
One of the reasons why I want to establish criteria to highlight the more important aspects of the scope, things that would be more important to the user. This why when say asks, hey I see a yellow ring around the edge, we can stop it right there and say, Ya, just a wide-open FOV and that is a reflection off the Field Stop and not an issue. End of story, no debate.
The fact is, people are going to compare whether we like it or not and it may be an apples to oranges comparison. Is it "fair" to compare a ZCO ZC420 to a ZP5 3-15 when the ZP5 is your more traditional design while the ZCO is an Ultra Short design? I don't think it's about fairness but about what choices are available (and what I might have available to review). I state in my review the 3-15 is NOT an ultra short but was used more or less as a baseline to see how the ultra shorts compare to a proven design or vice versa. I do not think it is too far off to think that someone who might be thinking of a 3-20 , 3.5-18 or 4-20 design might also consider a 3-15 regardless of size. My reviews do include comparison for the simple fact that is what I do when trying to decide on a scope, I try my best to list my biases and inform those reading my reviews that I do have bias, there are certain aspects of scopes that I prefer over others, but in the end I try my best to be honest and share my observations from my own perspective. The fact is, the ZCO ZC420 exhibited a strange yellow halo that could not be seen in either the Schmidt US 3-20 or the Kahles K318i, regardless of FOV or field stop, etc. it was an observation and since I had not seen this before in any of the alpha scopes I thought I'd mention it to see if there was an explanation for it. You'll also notice this halo did not hinder me from saying that I feel the ZCO ZC420 is the best ultra short scope on the market right now with regard to overall mechanical/optical performance, that is my opinion and I'm sure others will have a different opinion. The new Schmidt DT II+ turrets appear to be a vast improvement over the previous generation PM II (18 mil DT) turrets and while I still think the ZCO has an optical edge, the Schmidt does have wider FOV and greater magnification range so with the new DT II+ turrets I think moves it closer to the ZCO.
I do like the idea of what you're trying to do with the new rating system but I also believe that many shooters will still ask for comparisons, "should I get a ZCO 4-20 or a Schmidt US 3-20 and why" and while we might nitpick the nuances the comparison can still benefit those on the hunt for these optics, especially when they cannot see before they buy. My reviews began with my own insatiable desire to find out for myself how different scopes perform in different situations and the only way I could do that was to buy multiple and put them all to the test, the comparison is what showed me the differences between each and I found that valuable.
It’s all just opinion,
you had an opinion why, not a fact .
until you get a machine to test one against the other, you are giving a subjective opinion on A vs B . Those two can have very similar or distinct design differences and last I saw, nobody is doing a tear down. This goes back to picking favorite colors, it’s one thing to single out distinct design features, it’s another thing to look at glass, and opine on the quaility
go look at a telescope forum, when they opine they use facts, they break down the individual lenses. They know what lens does what And what they can’t do. it shuts down a lot.
my biggest issue, you don’t let it go, you admit it confused you, but still you wrote a book again on something you said had no bearing on your personal rating, but here we are dragging it out.
it’s not a good look and it’s a boring read.
you had an opinion why, not a fact .
until you get a machine to test one against the other, you are giving a subjective opinion on A vs B . Those two can have very similar or distinct design differences and last I saw, nobody is doing a tear down. This goes back to picking favorite colors, it’s one thing to single out distinct design features, it’s another thing to look at glass, and opine on the quaility
go look at a telescope forum, when they opine they use facts, they break down the individual lenses. They know what lens does what And what they can’t do. it shuts down a lot.
my biggest issue, you don’t let it go, you admit it confused you, but still you wrote a book again on something you said had no bearing on your personal rating, but here we are dragging it out.
it’s not a good look and it’s a boring read.
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This just doesn't make sense to me. The yellow halo I observed in the ZCO is not an opinion, it is a fact - that is what I observed and what some others have observed as well. Some people don't like the thick white lettering on the ZCO, it's their opinion but does it have a bearing on their decision, for some it does, so are you saying we shouldn't have opinions? Some people don't like the color of the Razor Gen II - has no bearing optically or mechanically, but comes down to opinion. If we relegate reviews to simply a number we are back where we started - what does that really mean? A Schmidt gets an 8, a ZCO gets a 9 and a Tangent gets a 10... what does that really tell you? And aren't the numbers themselves really based on opinion?
I agree, until any of us get a machine to do testing in controlled situations with calibrated equipment we aren't going to have accurate machine tested/validated analysis, but even then those numbers don't tell the whole story. Very similar to MTF charts for camera lenses, those charts are produced from machines, but the numbers don't always tell the whole story - the story that only the human eye can tell which comes down to opinion based on what you see. I try my best to evaluate scopes in the same environment, but I'm human and there may be times where I mess something up, I encourage others to correct me if I say or do something wrong. I suppose that is what you're doing here, you're saying it was wrong of me to point out that the ZCO has a yellow halo, but this is not an opinion, it is a fact based on my observation, so are you suggesting I should have never mentioned the halo, if that is the case, it is now sounding more like a marketing document that only states what is good about said item. This is, in part, what led me to the Hide years ago, I appreciate that I could get honest feedback (opinions) from users, and not just marketing rhetoric often seen in magazines that are biased based on the amount of advertising dollars they get from manufacturers. This is what I have striven to achieve with my reviews - honest feedback based on my observations, and yes, that is going to include opinion (scope A exhibited more CA than scope B).
Again, I am struggling to figure out what you are saying I am doing wrong here and how it has been a disservice to the community?
You don't get it, I have explained the issue, which is you don't get it and then you don't let it go
Trust me on this, the industry reads what you post, and they don't really like what you have to say, they find fault with the little things you tend to harp on which by your own admission above, has very little bearing on the end-user.
Your focus is in the wrong place, and I believe you use these things to justify stuff, it reads, "I don't understand this part of it, but it seems wrong so every one look at this thing I consider a problem and let's talk about it until we are bored". Knows enough to be dangerous is a phrase that can apply.
Nothing wrong with an opinion, but when you constantly harp on this stuff it gets old fast,
I think you stopped doing a service when you started heading down these rabbit holes, trying to find a reason to say no. You are comparing stuff so close to each other, you are desperate to find a problem in order to award a winner. In these cases, it's not a case of winner or loser but you frame it that way.
Opinions are great, I post mine every day, this is my observation based on discussions I have had with more than one vendor. Your name comes up and it's not really something I think you would enjoy, but continue to do you, I am not gonna stop ya.
you're absolutely right, it's your opinion so run with it
Trust me on this, the industry reads what you post, and they don't really like what you have to say, they find fault with the little things you tend to harp on which by your own admission above, has very little bearing on the end-user.
Your focus is in the wrong place, and I believe you use these things to justify stuff, it reads, "I don't understand this part of it, but it seems wrong so every one look at this thing I consider a problem and let's talk about it until we are bored". Knows enough to be dangerous is a phrase that can apply.
Nothing wrong with an opinion, but when you constantly harp on this stuff it gets old fast,
I think you stopped doing a service when you started heading down these rabbit holes, trying to find a reason to say no. You are comparing stuff so close to each other, you are desperate to find a problem in order to award a winner. In these cases, it's not a case of winner or loser but you frame it that way.
Opinions are great, I post mine every day, this is my observation based on discussions I have had with more than one vendor. Your name comes up and it's not really something I think you would enjoy, but continue to do you, I am not gonna stop ya.
you're absolutely right, it's your opinion so run with it
Duly noted. I will attempt to not "harp" on minor items in the future. I have no doubt that some of the things I say would not be popular with vendors, but I had no idea I had that much weight to be honest; my goal has always been to serve the people and share my findings in an honest and straightforward manner but you've pointed out it has not been as straightforward as I used to be so I will work on getting back to that.
I've enjoyed your write up, wjm308. I have a S&B 5-20 that I love, and K318 that I love, and am on a wait list for a ZCO with the new reticle. I agree with your findings on the S&B and K318. I almost posted a thread comparing mine like you did yours, but decided not to because I don't feel like catching the flak that you are catching.
I actually learned a lot about optics in this thread. I never knew about how length of the scope body can affect things or how a wide a FOV can affect things (yellow ring issue)...
If the manufactures don't like some of the things you point out in their optics(CA, narrow FOV, yellow ring, etc). That is their issue. I get google reviews of my business all the time... many are great but some are not. I've actually corrected a few issues within the company, based off those reviews.
I'd like to see more reviews from you in the future.
I actually learned a lot about optics in this thread. I never knew about how length of the scope body can affect things or how a wide a FOV can affect things (yellow ring issue)...
If the manufactures don't like some of the things you point out in their optics(CA, narrow FOV, yellow ring, etc). That is their issue. I get google reviews of my business all the time... many are great but some are not. I've actually corrected a few issues within the company, based off those reviews.
I'd like to see more reviews from you in the future.
Thank you regency, I really appreciate that. I realize that I am opinionated and have the tendency to nitpick at times but I do try to write in such a way that gives the reader all the information based on my findings. I'm about to do a review of the Schmidt & Bender 5-45x56 vs. the new March 5-42x56 High Master and will try to not harp on certain things but simply state them and move on. I'm also going to try and evaluate based on Frank's numbering system so hopefully this will help in that regard.
WJM 308 I have always enjoyed your reviews on scopes and they have helped me to make decisions on the purchase of tier one scopes.Please keep up the good work that you have contributed to this forum.
Excellent Review!! Wish every review was through.
Great work.
On the issue of including agressive FOV stops in scopes to make them look better edge to edge vs having a bigger FOV with the distortion that will be present, I am for the bigger FOV. Most scope companies seem to go with a more aggressive FOV stop. I can understand their choice, the assumption is that it will look better on first glance to a prospective buyer whereas it takes a little research and understanding for the customer to notice the FOV difference, understand what is going on, and make the decision of wanting to see as much as possible even when some won't be perfect.
On the issue of including agressive FOV stops in scopes to make them look better edge to edge vs having a bigger FOV with the distortion that will be present, I am for the bigger FOV. Most scope companies seem to go with a more aggressive FOV stop. I can understand their choice, the assumption is that it will look better on first glance to a prospective buyer whereas it takes a little research and understanding for the customer to notice the FOV difference, understand what is going on, and make the decision of wanting to see as much as possible even when some won't be perfect.
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How far off is the MK 5 HD glass to the S&B and ZCO? I have owned S&B PM II before, but the MK 5 has some great glass in them. I would be curious to see it SXS with these and see if the Juice is worth the Squeeze?
Pretty far off in my experience, Mark 5HD 3.6-18x44 is a great scope, but it is not on the same level as Schmidt and ZCO. You get what you pay for with these scopes, now, whether you think the Schmidt or ZCO is worth over $1k more that is going to be up to the buyer.
I am not going past 300 90% of the time and 500 max really. So it’s hard for me and my application to justify the cost. However, I understand what everyone is saying..
you can get the job done at much further distances then 300 with much cheaper scopes then a mrk5. Its preference really, how much glass and features do you prefer? You'll always hit a point of diminishing return in everythinh not just scopes...ie cars... so its more a want and a must have then a need. So to say I only shoot 300 so I dont need to buy a 3600 dollar scope mine 2500 dollar scope is good enough is like saying I dont need a Ferrari to get me from a to b my Mercedes AMG is good enough. I dont drive too far anyways....well a civic would do just fine if that was your criteria.
I have one ZC420 MPCT1 shipping in 
Feel free to call us at 916-670-1103x2 to grab this one or order here:
www.cstactical.com
Feel free to call us at 916-670-1103x2 to grab this one or order here: ZCO 4-20x50 ZC420 Riflescope
The Zero Compromise Optic (ZCO) ZC420 is the ultimate solution for all your target engagement requirements.
www.cstactical.com 
You revived a 4 month old thread to say thanks. Only 99 more of those and you can sell stuff.
Not interested in selling anything, I'm not based in the US. You will NEVER see me post a For Sale here.
I am genuinely greatful for the information in the review, which must have taken some time to write. And I learned a few things reading it, so out of courtesy I wanted to thank the writer. Sorry if it bothered you.
Ok. However, that’s not usually the case here when someone has several posts hours after joining.
Plus, you could always PM someone you’re appreciative of. By posting, you move the 4 month old thread back to the top...which also pings anyone watching (or previously posted in) the thread. Add in everyone interested in the topic that sees new posts.... they all open the thread, scroll all the way to the bottom...only to find someone that just joined, said thanks.
Anyways, I’ve said my piece, and so now I’ll stop posting in this old thread too.
Welcome to the Hide. The amount of resident knowledge and talent here is profound and something I’m continually impressed by.
Plus, you could always PM someone you’re appreciative of. By posting, you move the 4 month old thread back to the top...which also pings anyone watching (or previously posted in) the thread. Add in everyone interested in the topic that sees new posts.... they all open the thread, scroll all the way to the bottom...only to find someone that just joined, said thanks.
Anyways, I’ve said my piece, and so now I’ll stop posting in this old thread too.
Welcome to the Hide. The amount of resident knowledge and talent here is profound and something I’m continually impressed by.
Ok. However, that’s not usually the case here when someone has several posts hours after joining.
Plus, you could always PM someone you’re appreciative of. By posting, you move the 4 month old thread back to the top...which also pings anyone watching (or previously posted in) the thread. Add in everyone interested in the topic that sees new posts.... they all open the thread, scroll all the way to the bottom...only to find someone that just joined, said thanks.
Anyways, I’ve said my piece, and so now I’ll stop posting in this old thread too.
Welcome to the Hide. The amount of resident knowledge and talent here is profound and something I’m continually impressed by.
If you don't want to get the ping you can choose not to get it in the settings
I've been lurking for years, thanks for the warm welcome.
Perfect.If you don't want to get the ping you can choose not to get it in the settings
I've been lurking for years, thanks for the warm welcome.
Oh wait... there’s no ping setting that differentiates between a useful post, and one from someone that joined 5 min ago looking for PX privileges....which was the whole point I was making.
Again, maybe that’s not you...but if you’ve been lurking for years, you’d already know that’s a common problem...and wouldn’t be arguing for its practice.
You mean like the ping you just did?
Again, I'm not looking for any privileges but if I was you sure helped out. LOL.
I now have my hands on a production model March 4.5-28x52 High Master. This is the highest magnification ultra short model I know of to date with a FOV that beats every other scope in its class. I will be doing a review shortly and am curious to see if this newest scope from March can compete with the rest of the alpha class ultra short scopes.
I am interested to hear what you think.
Me too.
If anyone's interested to read and see more about the Schmidt & Bender 5-20×50 PM II Ultra Short Series check out the link.
I did a retciel change to MSR2, and it's totally worth it in my opinion.
There's also pictures with the Pulsar Krypton Thermal clip-on, through-the-reticle pictures and some other goodies.
www.thefirearmblog.com
If anyone's interested to read and see more about the Schmidt & Bender 5-20×50 PM II Ultra Short Series check out the link.
I did a retciel change to MSR2, and it's totally worth it in my opinion.
There's also pictures with the Pulsar Krypton Thermal clip-on, through-the-reticle pictures and some other goodies.
TFB Review: Schmidt & Bender 5-20x50 PM II Ultra Short Series -
Looking to transform your high-quality AR-platform or bolt-action rifle from a being reasonably accurate to a precision instrument? Then the ultra compact Schmidt & Bender 5-20x50 PM II Ultra Short might be the answer.
Resurrection to oft overlooked Ultra Short 5-20, I actually liked that scope more than the Ultra Short 3-20, it is a fantastic scope and now with the DT II+ turrets is an even "better" scope. And at 11.8" it is truly the "Ultra" of the short scopes! But at just .8 inches longer, the March 4.5-28x52 is not too far off, and so far my comparison against my TT 5-25 show incredible promise for this scope from March!Me too.
If anyone's interested to read and see more about the Schmidt & Bender 5-20×50 PM II Ultra Short Series check out the link.
I did a retciel change to MSR2, and it's totally worth it in my opinion.
There's also pictures with the Pulsar Krypton Thermal clip-on, through-the-reticle pictures and some other goodies.
TFB Review: Schmidt & Bender 5-20x50 PM II Ultra Short Series -
Looking to transform your high-quality AR-platform or bolt-action rifle from a being reasonably accurate to a precision instrument? Then the ultra compact Schmidt & Bender 5-20x50 PM II Ultra Short might be the answer.
