If a manufacturer states that his binoculars are nitrogen filled and then goes on to state that all AIR to GLASS surfaces are multicoated, does that mean that only the front outer surface of the front objective and the exterior surface of the ocular lens, are the only surfaces multicoated? Since the interior lens surfaces are no longer subjected to AIR since being replaced with nitrogen? Also is there any advantage to nitrogen filled vs argon filled?
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clarification needed nitrogen filled and air to glass surfaces (1 Viewer)
- Thread starter cappi
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vop
Well-known member
Air is actually a gas mixture that is mostly (78%) nitrogen. The thing with filling the binoculars with DRY nitrogen (not containing water vapor) is that it makes it internally fog free. Argon, or any other nonreactive gas works as good, not better.
That all air to glass surfaces are multicoated should mean Fully MultiCoated.
That all air to glass surfaces are multicoated should mean Fully MultiCoated.
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Hi Cappi,
There is a simple explanation of coatings here:
http://www.celestron.com/c3/support3/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=1626
This is just the first site that popped up on Google. Essentially you should be looking for both fully multicoated and phase coated in roof prism binoculars for best performance.
Obviously water getting inside binoculars will do damage of one sort or another. When pairs are waterproofed, the oxygen and water vapour are usually flushed out and may be slightly pressurised. This is to inhibit microbial growth. I know of no evidence that argon has a practical advantage over nitrogen.
David
There is a simple explanation of coatings here:
http://www.celestron.com/c3/support3/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=1626
This is just the first site that popped up on Google. Essentially you should be looking for both fully multicoated and phase coated in roof prism binoculars for best performance.
Obviously water getting inside binoculars will do damage of one sort or another. When pairs are waterproofed, the oxygen and water vapour are usually flushed out and may be slightly pressurised. This is to inhibit microbial growth. I know of no evidence that argon has a practical advantage over nitrogen.
David
looksharp65
Well-known member
Nitrogen gas will leak out from the binocular faster than argon because the molecules are smaller. Argon is less reactive than nitrogen gas so silver coated prisms will be better protected against tarnish if argon is used.
OP was really witty - in fact it would be OK only to multicoat the outer surfaces since they are the only lens surfaces to encounter ordinary air.
EDIT: This is me quoting marketing claims and I have no evidence they're true. To me, the use of nitrogen is not a deal breaker as I think in reality the two gases are equal.
OP was really witty - in fact it would be OK only to multicoat the outer surfaces since they are the only lens surfaces to encounter ordinary air.
EDIT: This is me quoting marketing claims and I have no evidence they're true. To me, the use of nitrogen is not a deal breaker as I think in reality the two gases are equal.
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normjackson
Well-known member
Funny; remember this gaseous thread appearing on BF not long after Minox first made a deal about their use of Argon for purging :
http://www.birdforum.net/showthread.php?t=52292
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vop
Well-known member
It isn't the leaking out, but the leaking in (of moist air) that would be a problem. If you take the binos up to Mount Everest or something, the gas pressure might cause outward leakage... -I don't know.
I also think nitrogen is low reactive enough for it not to matter. Again -I don't know.
What?
If they wanted to fool the customer you mean?
To be really serious I doubt that nitrogen purged binoculars contain only nitrogen. Probably some oxygen and (forgot about the argon) carbon dioxide et c, so it would be air, with very high nitrogen content. Was that witty enough or am I just stupid?
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looksharp65
Well-known member
If they are gas filled under pressure, the pressure has to equalize, which means that gas must leave the binoculars before any other molecules can come into it.
The pressure prevents the intrusion of water, damp and gases that could harm the inside of the binoculars.
Agree that nitrogen is not a real problem even for silver coatings.
I think it's not ordinary air in the binoculars. Nitrogen is cheap.
Yes, if.
vop
Well-known member
I don't think binos are pumped up with gas, don't they just spray them with nitrogen (or argon) to purge the air?
My idea was that a little air remains, so the... :-O
Ahh! This is stupid anyway! Forget it all and go do something useful! B
looksharp65
Well-known member
I don't think binos are pumped up with gas, don't they just spray them with nitrogen (or argon) to purge the air?
My idea was that a little air remains, so the... :-O
Ahh! This is stupid anyway! Forget it all and go do something useful! B
You may be right. Some Steiner binoculars feature nitrogen pressure filling and two-way valves.
I guess that it would be possible to achieve a pressure filling without the use of valves if the final sealing of the bins is performed in a nitrogen filled pressure chamber.
But I have no idea if that is what really happens or if there are hidden valves under the armoring. Or if there's no pressure, a feasible assumption.
looksharp65
Well-known member
Is there pressure involved in the process?
Ok I get it with regards to the nitrogen vs argon issue. But still unclear as to if the INTERNAL glass surfaces are multicoated. Its the air to glass issue. If nitrogen or argon filled, then NO AIR internally,thus no coatings----correct? ? ? How about if instead they only stated FULLY multicoated ? The early link provided in this thread gave definitions of various levels of coatings. Fully multicoated was defined as coatings on "ALL" glass surfaces. So to keep it simple I should look only for fully multicoated because it does NOT distinguish between air,argon or nitrogen internally.
RJM
Don't Worry, Be Happy!
The "Air" is irrelevant. It's all about the "space". Even if a vacuum existed in the void between lenses you still want the two surfaces to be AR multicoated. When lenses are cemented together or the void is filled with oil then the two surfaces are "invisible" to the light.
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It had better mean every glass surface that is not cemented (or oil sealed) to the face of an adjacent surface, or me and all the other deceived binocular enthusiasts will riot. It does in fact mean that, in all the cases I've encountered. Look at the reflections of a white light behind you, shining down the barrel of a binocular. Every such exposed surface will show a reflection. Coated surfaces will show colored reflections, and the dimmer the reflection, the better the coating. A bright white reflection will be returned from uncoated surfaces.
I know I'm supposed to look through the other end, but I can't help it.
Ron
I know I'm supposed to look through the other end, but I can't help it.
Ron
Tvc15_2000
Well-known member
I believe an additional bonus to the gas is it prevents mold and fungus growth on the glass surfaces which used to be a problem on old gas porus binoculars.
The samples I have seen with this problem look like a white fog (also comes in other colors) over the glass. Sort of like moisture fogging - but it does not clear. This problem makes the binocular un-useable or seriously degrades the performance and can not be corrected as far as I am aware.
The samples I have seen with this problem look like a white fog (also comes in other colors) over the glass. Sort of like moisture fogging - but it does not clear. This problem makes the binocular un-useable or seriously degrades the performance and can not be corrected as far as I am aware.
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