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The most common failure in riflescopes is due to the springs at the 9 o'clock and 6 o'clock position. These springs get worn or break or get dislodge or whatever and the adjustment screw no longer has anything to works against.

I have heard of issues with lenses that move or spin (reticle) and issues with the zoom lenses and so on. I have also heard of issues with the clicking mechanism on adjustment screws freezing up.

I have (somewhere) an old 4X Tasco that I bought 45 years ago. The springs gave up the ghost. So I took apart to see how it was put together. I learned stuff.
 
Posts: 2832 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
Freethinker
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Thanks again for all this information. I have been around rifle scopes for a long time without knowing much of what you are telling us.
 
Posts: 39107 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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Originally posted by NikonUser:
I have (somewhere) an old 4X Tasco that I bought 45 years ago. The springs gave up the ghost. So I took apart to see how it was put together. I learned stuff.


I should have been more specific in my question. Back in the mid 80's I used to sell high end camera equipment. At that point the camera industry was moving towards lighter less expensive cameras for the masses, and auto focus was just making inroads into the consumer optics industry. Nikon and Cannon dominated the professional camera market, and their stuff was heavy compared to Minolta, Olympus, and Pentax due to the latter two companies use of brass and steel. Olympus was a pioneer in this field, followed by Nikon with their consumer products line of non professional equipment. Companies replaced brass and steel with aluminum and nylon\plastic gearing and races. What we shortly started seeing was lots of stripped and broken gearing, and lenses that wouldn't track correctly.

I've seen a lot of complaining over the last 20 years on how former reliable scope companies have gone to poo in terms of quality internals because the general market is price point driven. These days everyone has access to good glass, so some companies cut corners with internal components. It appears that while everything can break, the major players in the competition optics industry are still using quality internal components.


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Posts: 6053 | Location: Newyorkistan | Registered: March 28, 2007Reply With QuoteReport This Post
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SgtGold, I get you now.

I've been into photography since the late 60s, early 70s and I saw some of the same stuff you mentioned. Nikon and Canon (one n) have been at the top of the heap for a long time, but Leica, Hasselblad and others had their excellent stuff also.

In the 80's a lot of plastic and aluminum parts was introduced in the lower end cameras, that didn't have the duty cycles of the professional stuff. People like the light weight and when you only take a few pictures every year, big deal.

Riflescopes are the same and different at the same time. The tubes are virtually all aluminum, but it's the fittings and the inner parts that can and will make a difference.

Nightforce has developed a reputation for being solid, and they have the weight to go with that. I can't remember a time when I had any issues with the optics of a scope, such as adjustable objective, side focus, zoom or diopter adjustment on the eyepiece. I listed earlier the types of issues that I've heard about or seen, but I'm sure there are a lot more issues that can arise. After all these devices are mechanical and people find new methods of abuse, even beyond the factory defects.

That's why they have warrantees.

I just found a cheaper lens that I bought back in 1982 or so for a Minolta. It is still silky smooth, but heavy.

Then again my 18-300mm is a porker.
 
Posts: 2832 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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NikonUser I know you like your March scope. Was wondering if you have had the opportunity to compare it to some of the other new FFP with ED glass offerings out there and what was your opinion of them. I'm primarily a PD shooter who likes to shoot at the long shots and the heat waves kill me during the day. Your earlier post about the glass helping got me thinking of moving up.



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Posts: 593 | Location: Northern Alabama | Registered: June 21, 2005Reply With QuoteReport This Post
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I never get a chance to look through FFP riflescopes; that's the problem with extreme specialization. I would hope that others here who use FFP scopes will chime in. In the meantime, let me offer these thoughts.

To beat the mirage, you need two things in my opinion, get better glass and reduce the depth of field . My impression is that ED glass minimizes the effect of mirage, which is really a shimmering cause by different temperature air currents and humidity. I believe (however wrong that notion is) that ED glass's capacity for reducing or eliminating chromatic aberration is responsible for that. Bring on the formulae that prove me wrong, I just think better glass and ED glass at that, erases a lot of mirage effects. Reducing the depth of field is a little complex with a riflescope compared to a camera, but it can be done. The depth of field is the region in front of and behind the distance at which you have focused your lens (camera or riflescope.) This region varies as a function of distance, magnification and aperture. Nothing you can do about the first one, the target is where the target is. DOF is reduced as you increase the magnification of the lens. The aperture is not something we control easily on a riflescope, but the bigger the front lens, and the inner lenses, the wider the aperture. The wider the aperture, the smaller the DOF. My March-X has a 56mm objective and a 34mm tube with bigger internal lenses. It has a much bigger aperture than any 30mm or 1 inch scope with 40 or 44mm objectives.

When the mirage got bad last time, I increased the power from the usual 40X at which I shoot to 50X to reduce the DOF. I do know that most people reduce their magnification, but that catches more mirage. The reason they think they see better is that the target is smaller and the mirage distortions are thus smaller. I think they're wrong, but that's just me and I could be the one that's wrong.

I also know that some people put masks or apertures on their riflescope, to INCREASE DOF. They want to catch more mirage. You can also do that with a dark yellow or red filter or even an NC filter. I've been thinking of trying our a circular polarizer on my spotting scope to see if that helps me catch more mirage. These are fairly expensive for 80mm tubes, and I hate to spend upwards of a C-note just to try something that most likely will not be worth it.

As I said earlier, I want the best glass on my rifle and good glass on the spotting scope.
 
Posts: 2832 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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Originally posted by NikonUser:

We currently live in a golden age of optics, with new technology coming in at a fast and furious pace. The low price optics of today are optically better than the top end stuff of yesteryear.



First, thanks for the post.

Second, I can echo your comment above. My sons and I have my father-in-law's Weatherby rifles from the late '50s and '60s. The rifles are great. The scopes, not to put too fine a point on it, sucked. And theses were quality, German-made optics. But the cheapest scope from Wal-Mart is better than those 60 year old scopes.




The fish is mute, expressionless. The fish doesn't think because the fish knows everything.
 
Posts: 47063 | Location: Texas | Registered: February 10, 2004Reply With QuoteReport This Post
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Someone is paying attention.

I was absolutely agog when on another thread, it was reported that a $600 Nikon scope had ED glass.

Agog, I tell you.

And yes, the 50s and 60s optics would have had no lens coating. This makes the image bland and with low contrast.
 
Posts: 2832 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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NikonUser, you have often mentioned using filters with various optics. Do you just use the filters designed for photographic lenses? And how do you determine the proper size; is it just the nominal objective lens diameter? For example, I have spotting scopes that I would like to protect with filters. One is a Swarovski ATS 65 HD, which I understand to have a 65mm objective lens, and the other is a Leupold 12-40×60mm. Would I use 65mm and 60mm filters, respectively, for the two?




“Without its tough spearmen, Hellenic culture would have had nothing to give the world. It would not have lasted long enough. When Greek culture became so sophisticated that its common men would no longer fight to the death, as at Thermopylae, but became devious and clever, a horde of Roman farm boys overran them.”
— T. R. Fehrenbach, This Kind of War
 
Posts: 39107 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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Yes, I use filters for camera lenses. Be careful though, you want to get a good quality one, especially if your rifle kicks a lot. The last thing you want is a filter that breaks when you shoot.

As for the size, all lenses, riflescopes, spotting scopes and filters use the same thread. When you buy a camera lens the filter size is part of the specs, not so for riflescopes and spotting scopes. What I do is add 6mm to the objective size and buy that filter. So a 56mm lens requires a 62mm filter.

Your 60mm Leupold should have a 66mm filter size. If you go to the Swarovski site, the specs for the ATS 65 say that the filter thread is 67. I'm a little surprised by that, but I was also surprised to see an odd number for an objective lends diameter. Then I notice that the image shows the filter thread to be very close to the objective lens; there's virtually no meat there. It's a different construction than what I'm used to.
 
Posts: 2832 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
Freethinker
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Okay, thank you very much as always for your informative reply. It didn’t occur to me to try to find an actual spec for the filter size.

The strangest experience I’ve had was when I was trying to obtain a sunshade for a Leupold 3-18×44mm sight. Leupold didn’t/doesn’t offer a shade for that scope and when I asked for the size specification in an attempt to determine if a shade by another manufacturer would work, I got an email back saying that that information couldn’t be released because of ITAR restrictions. I composed a … vigorous letter to the company president about that response, but never sent it.

Added: I remembered that I have a 67mm adapter ring, and it does fit the Swarovski. On the other hand, I cannot find a listing for any 66mm filters or even adapter rings.




“Without its tough spearmen, Hellenic culture would have had nothing to give the world. It would not have lasted long enough. When Greek culture became so sophisticated that its common men would no longer fight to the death, as at Thermopylae, but became devious and clever, a horde of Roman farm boys overran them.”
— T. R. Fehrenbach, This Kind of War
 
Posts: 39107 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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Yeah, it's one if the reasons I despise Leupold, but let's keep that between us. I would try a 67mm filter. Those are common.
 
Posts: 2832 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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Update for the OP.
I just found out that the riflescope company that was rumored to be on the verge of bringing out a riflescope with fluorite glass, has just released a riflescope with "super-ED" glass, not fluorite.

The March High Master series features such glass and should be shipping soon.

Super-ED glass is essentially better Extra-low Dispersion glass, which should virtually eliminate chromatic aberration and in my opinion, further attenuate the shimmering effect known as mirage, in the riflescope.

This really is the golden age of optics.

Stay tuned.
 
Posts: 2832 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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After reflecting on what sigfreund had said earlier, and finally remembering that I had bought a filter for my Kowa TSN-82SV spotting scope with the 82mm objective lens, I checked the filter size. It is an 86mm filter, so only 4mm wider than the objective lens.

This now leads me to believe that while I have not yet seen a riflescope that did not accept a filter 6mm wider than the objective lens, this "rule" does not seem to apply to spotting scopes. So, caveat emptor.

I pulled out my trusty (non-rusty) caliper and measured the inside diameter of the threads on the Kowa and came up with something between 85 and 86mm. Rounding that up to 86 was the proper filter size. Checking quickly on a couple different riflescopes, I do come up with between 5 and 6mm over the stated objective size.

If the filter size you think you need is not easily found at Amazon or BHPhotovideo, you probably did not measure correctly, look at what's available near that size.
 
Posts: 2832 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
Freethinker
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Thanks for all that, NikonUser. I tried screwing a 67mm filter into the Leupold spotting scope and although it seemed like it was the right size, the rubberized ring that’s part of the “armor” on the scope kept it from going in properly (I believe). I gave up, but need to pursue it again, possibly by pushing the ring away.

Now I’m also trying to figure out how to attach a polarizing filter to my Mark 6 3-18×44mm scopesight. I have a Tenebraex adapter ring that actually fits the thread of the sight, but its size isn’t indicated. I’m thinking of taking it to a good photo shop to see if they’ll help me determine what it is. Alternately because it might be easier to use in the field, I’d like to find a nonthreaded slip type clamp-on filter holder that would fit the sunshade that’s normally attached to the sight. The external diameter of the shade is ~50mm, though, and none of the clamp-on holders I’ve found would fit. In addition the clamp-ons I found are designed for very large filters.

In addition, I discovered that these days it’s difficult to find a “linear” polarizing filter; most are circular. Back (way back!) when I was very involved in photography, the circular filters were the rarity and I don’t have any of that type. My question is do circular polarizing filters act the same way in eliminating reflections from things like glass and water surfaces?

Thanks again for your help.




“Without its tough spearmen, Hellenic culture would have had nothing to give the world. It would not have lasted long enough. When Greek culture became so sophisticated that its common men would no longer fight to the death, as at Thermopylae, but became devious and clever, a horde of Roman farm boys overran them.”
— T. R. Fehrenbach, This Kind of War
 
Posts: 39107 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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Originally posted by sigfreund:
In addition, I discovered that these days it’s difficult to find a “linear” polarizing filter; most are circular. Back (way back!) when I was very involved in photography, the circular filters were the rarity and I don’t have any of that type. My question is do circular polarizing filters act the same way in eliminating reflections from things like glass and water surfaces?

Thanks again for your help.


The short answer is yes. One thing to be aware of is they make polarizing filters that allow you to adjust the level of light you let through. Ultra Dot sells them on their web site. I was shooting a pistol match and my red dot went black. I mean opaque black like someone shut the cap. The recoil from each shot slowly moved the adjustable ring and it went far enough that the filter shut off my light.


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Posts: 6053 | Location: Newyorkistan | Registered: March 28, 2007Reply With QuoteReport This Post
Freethinker
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Originally posted by SgtGold:
One thing to be aware of is they make polarizing filters that allow you to adjust the level of light you let through.


Thank you. As I say, I have no experience with circular polarizing filters and although I once knew how they differed from the linear type, that was long ago.

The type of filter you describe that I’m familiar with uses two filters together to achieve that dimming, and I would definitely avoid it. I’m not seeking to adjust the light transmission level, but to eliminate reflections from glass.




“Without its tough spearmen, Hellenic culture would have had nothing to give the world. It would not have lasted long enough. When Greek culture became so sophisticated that its common men would no longer fight to the death, as at Thermopylae, but became devious and clever, a horde of Roman farm boys overran them.”
— T. R. Fehrenbach, This Kind of War
 
Posts: 39107 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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The circular polarizers showed up so that AF and AE would still work on newer cameras. They work fine on optics, just like before.
 
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Freethinker
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Originally posted by NikonUser:
The circular polarizers showed up so that AF and AE would still work on newer cameras. They work fine on optics, just like before.


Thanks. Any suggestions about a way of attaching a polarizing filter to the scope I mentioned above?
 
Posts: 39107 | Location: 10,150 Feet Above Sea Level in Colorado | Registered: April 04, 2002Reply With QuoteReport This Post
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For those who may not be aware, slapping a quality polarizer lebs on yor camera will produce dramatic sky scenes with ominous clouds. This is especially marked when shooting at 90 degrees from the Sun. You will also psee in water quite well, best done at about 35 degrees angle into water. You'll loose about 3 f-stops of exposure.
 
Posts: 2832 | Location: Texas | Registered: June 20, 2012Reply With QuoteReport This Post
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