Lightweight Composite on lenses?

[jeffnles1]

I didn't want to hijack Ronald's thread asking about lightweight / lighter weight equipment for photography so I'll start a new thread.

Other than tradition and most of us being somewhat traditionalists, is there a good reason why lens manufacturers shy away from using modern lightweight composite materials for lens barrels? I can see huge advantages with little downsides and wanted to hear your opinions and thoughts
Pro as I see it:
Lighter Weight than steel or aluminum
Highly Durable (Glock pistols and military M4 rifles take far more abuse than any camera ever will and they hold up to that abuse in specular fashion.)
High tensile, impact, and shear strength
resists warpage and expansion due to temp changes
Not as "cold" to the hands during cold weather
It will not dent if dropped (scratch but not dent)

Cons as I see it:
Not traditional, photographers say "Plastic" without giving it further consideration
Probably does not save much money as these materials are as expensive to make as it is to make equal part from aluminum or steel.
Not sure exact weight savings, what percent of a lens' weight is the barrel vs. the glass?


What are your thoughts?
Jeff

 

[Replytoken]

This discussion often end up in a Coke vs. Pepsi or Ford vs. Chevy type discussion because a lot of answers are based on emotion or stories (often heard on the web) about what happened in one instance. I think that you summed it up reasonably well, and we'll never really know if materials changes were made for the sake of design and durability or cost savings (and sometimes both can be accomplished). Having read more than my share of posts, I can also say that some people really like how a piece of equipment feels in hand, despite how it can perform. I get that to a point, but I am also happy when equipment is lighter and just as durable. Interesting to see where this thread heads, although most forum members are quite well behaved so I do not expect it to go off the rails.

--Ken

 

[hef19898]

All Z mount lens barrels are made of a magbesium alloy already. As where a ton of Af-S F mount ones, basically every Nikkor lens that Ken Rockwell derided of being made of "cheap plastic" was. Nikon, and others (I know next to nothing about other brands), didn't care what traditionalists said. And their Z lenses, excluding only the NOCT, are universally praised despite being mostly composite of sorts.

Carbon composite, the stuff most people think of when talking about composite materials, is extremely difficult to produce as tubes, read very expensive. Especially if you want to machine to the tight tolerances needed for something like lens barrels. Carbon composite barrels, and other tube like structures are almost exclusively used when:

- you need to save weight regardless of cost (aerospace for example)

- need high mechanical strength but cannot use steel / titanium (small stuff, stuff under a lot of dynamic load like robot arms where weight is zo be avoided, somewhat linked to above

- for stuff under a lot of internal pressure (scuba tanks, pressure vessels and such that benefit from less weight; absolutely not for things under external load, the Titan sub shows you why)

- when you want to sell "aerospace grade carbon composite" as a marketing gadget to drive consumer prices up for the clueless public (car "tuning" parts, camping gear...)

For everything else, other materials are better. And those are used. The reason Viltrox and others are using aluminium and steel is simole: cheaper and easier to machine.

Edit: I see this all the time lay people discuss engineering topics, discussions are ignoring almost everything about engineering. I am no different for topics outside my areas of expertise. One can be pretty sure so, that engineers developing certain products know pretts well what they are doing. Within then constraints of course, those range from cost to weight to size to design and hard and physical ones. And every public engineering screw up, real ones, not the perceived ones, are simply the exceptions proofing the rule.

 

[Jonathan]

I didn't want to hijack Ronald's thread asking about lightweight / lighter weight equipment for photography so I'll start a new thread.

Other than tradition and most of us being somewhat traditionalists, is there a good reason why lens manufacturers shy away from using modern lightweight composite materials for lens barrels? I can see huge advantages with little downsides and wanted to hear your opinions and thoughts
Pro as I see it:
Lighter Weight than steel or aluminum
Highly Durable (Glock pistols and military M4 rifles take far more abuse than any camera ever will and they hold up to that abuse in specular fashion.)
High tensile, impact, and shear strength
resists warpage and expansion due to temp changes
Not as "cold" to the hands during cold weather
It will not dent if dropped (scratch but not dent)

Cons as I see it:
Not traditional, photographers say "Plastic" without giving it further consideration
Probably does not save much money as these materials are as expensive to make as it is to make equal part from aluminum or steel.
Not sure exact weight savings, what percent of a lens' weight is the barrel vs. the glass?


What are your thoughts?
Jeff

I’m certainly no expert here but I think most the weight of a lens would be from the glass elements vs the barrel.

I believe a lot of the Canon RF lenses utilize engineering plastic in the barrels.

For example, this quote from the “Build Quality and Features” section of this (https://www.the-digital-picture.com...-7.1-L-IS-USM-Lens.aspx#BuildQuality&Features) Canon 100-500mm lens review states “Much of the lens exterior is constructed of high-quality engineering plastic.”

 

[bleirer]

I think the choices have to include all the relevant properties of a material and the tradeoffs involved. For example every material expands or contracts based on temperature, but some more than others, some materials might be stiff but not strong or vice versa. So it is more than just being light, but that I'm sure is one property.

 

[jeffnles1]

I think the choices have to include all the relevant properties of a material and the tradeoffs involved. For example every material expands or contracts based on temperature, but some more than others, some materials might be stiff but not strong or vice versa. So it is more than just being light, but that I'm sure is one property.

That is why I included a lot of other properties vs. just weight. If we look to the firearms industry, even the slightest of movement in the frame or stock components can make huge differences in aim point vs. impact point. Some very serious competition firearms are made with frames and stocks and grips of composites.

I'm not pushing for one just curious of why, other than tradition, do lens makers not utilize it more? I'm not trying to stir up debate but ask a question to get thoughts.
Thanks.

 

[JAJohnson]

All Z mount lens barrels are made of a magbesium alloy already. As where a ton of Af-S F mount ones, basically every Nikkor lens that Ken Rockwell derided of being made of "cheap plastic" was. Nikon, and others (I know next to nothing about other brands), didn't care what traditionalists said. And their Z lenses, excluding only the NOCT, are universally praised despite being mostly composite of sorts.

Edit: I see this all the time lay people discuss engineering topics, discussions are ignoring almost everything about engineering. I am no different for topics outside my areas of expertise. One can be pretty sure so, that engineers developing certain products know pretts well what they are doing. Within then constraints of course, those range from cost to weight to size to design and hard and physical ones. And every public engineering screw up, real ones, not the perceived ones, are simply the exceptions proofing the rule.

Cost, weight, durability, how it ”feels” in the hand, toxicity, ease of repair/maintenance, and recyclability. These are all factors which consumer hardgoods producers take into account.

 

[jeffnles1]

I’m certainly no expert here but I think most the weight of a lens would be from the glass elements vs the barrel.

I believe a lot of the Canon RF lenses utilize engineering plastic in the barrels.

For example, this quote from the “Build Quality and Features” section of this (https://www.the-digital-picture.com...-7.1-L-IS-USM-Lens.aspx#BuildQuality&Features) Canon 100-500mm lens review states “Much of the lens exterior is constructed of high-quality engineering plastic.”

I have the 100-500 lens and it is certainly light weight for its size and focal range.

Would be interesting to hear some of the engineers weigh in on the reasoning.

I have shot tens of thousands of rounds of ammo through polymer / composite frame firearms and outside of intentional abuse (someone seeing how much abuse can be applied before breakage) never seen one fail due to problems with the frame.

Thanks for responding, I'm really curious about this topic.

 

[jeffnles1]

This discussion often end up in a Coke vs. Pepsi or Ford vs. Chevy type discussion because a lot of answers are based on emotion or stories (often heard on the web) about what happened in one instance. I think that you summed it up reasonably well, and we'll never really know if materials changes were made for the sake of design and durability or cost savings (and sometimes both can be accomplished). Having read more than my share of posts, I can also say that some people really like how a piece of equipment feels in hand, despite how it can perform. I get that to a point, but I am also happy when equipment is lighter and just as durable. Interesting to see where this thread heads, although most forum members are quite well behaved so I do not expect it to go off the rails.

--Ken

I certainly hope it doesn't devolve into fight. If it does, I'll request the moderators to shut it down. My intent was to discuss what folks thought about it based on rational analysis not internet myth. From feel in hand, my experience has been metal frames get really hot in the sun and get really cold to the touch in winter where the composite / polymer frames are more comfortable to the touch at both ends of the spectrum.

Thanks for responding.
Jeff

 

[jeffnles1]

All Z mount lens barrels are made of a magbesium alloy already. As where a ton of Af-S F mount ones, basically every Nikkor lens that Ken Rockwell derided of being made of "cheap plastic" was. Nikon, and others (I know next to nothing about other brands), didn't care what traditionalists said. And their Z lenses, excluding only the NOCT, are universally praised despite being mostly composite of sorts.

Carbon composite, the stuff most people think of when talking about composite materials, is extremely difficult to produce as tubes, read very expensive. Especially if you want to machine to the tight tolerances needed for something like lens barrels. Carbon composite barrels, and other tube like structures are almost exclusively used when:

- you need to save weight regardless of cost (aerospace for example)

- need high mechanical strength but cannot use steel / titanium (small stuff, stuff under a lot of dynamic load like robot arms where weight is zo be avoided, somewhat linked to above

- for stuff under a lot of internal pressure (scuba tanks, pressure vessels and such that benefit from less weight; absolutely not for things under external load, the Titan sub shows you why)

- when you want to sell "aerospace grade carbon composite" as a marketing gadget to drive consumer prices up for the clueless public (car "tuning" parts, camping gear...)

For everything else, other materials are better. And those are used. The reason Viltrox and others are using aluminium and steel is simole: cheaper and easier to machine.

Edit: I see this all the time lay people discuss engineering topics, discussions are ignoring almost everything about engineering. I am no different for topics outside my areas of expertise. One can be pretty sure so, that engineers developing certain products know pretts well what they are doing. Within then constraints of course, those range from cost to weight to size to design and hard and physical ones. And every public engineering screw up, real ones, not the perceived ones, are simply the exceptions proofing the rule.

Good to hear an engineer chime in. I'm an IT guy not an engineer. Having been involved in the firearms game for a very long time (50 years) I do know the slow uptake on composite frame materials was largely due to consumer demand (don't want no cheap plastic pistol), and political (fear and ignorance about what can and cannot be seen in metal detectors) and traditionalist views in the management of the companies. Once these hurdles were overcome, now most new firearms (at least handguns) are made of composites and the stocks of most long guns are also a composite material vs. wood.

Interesting perspective from an engineer. Thanks for your insight.

 

[jeffnles1]

All Z mount lens barrels are made of a magbesium alloy already. As where a ton of Af-S F mount ones, basically every Nikkor lens that Ken Rockwell derided of being made of "cheap plastic" was. Nikon, and others (I know next to nothing about other brands), didn't care what traditionalists said. And their Z lenses, excluding only the NOCT, are universally praised despite being mostly composite of sorts.

Carbon composite, the stuff most people think of when talking about composite materials, is extremely difficult to produce as tubes, read very expensive. Especially if you want to machine to the tight tolerances needed for something like lens barrels. Carbon composite barrels, and other tube like structures are almost exclusively used when:

- you need to save weight regardless of cost (aerospace for example)

- need high mechanical strength but cannot use steel / titanium (small stuff, stuff under a lot of dynamic load like robot arms where weight is zo be avoided, somewhat linked to above

- for stuff under a lot of internal pressure (scuba tanks, pressure vessels and such that benefit from less weight; absolutely not for things under external load, the Titan sub shows you why)

- when you want to sell "aerospace grade carbon composite" as a marketing gadget to drive consumer prices up for the clueless public (car "tuning" parts, camping gear...)

For everything else, other materials are better. And those are used. The reason Viltrox and others are using aluminium and steel is simole: cheaper and easier to machine.

Edit: I see this all the time lay people discuss engineering topics, discussions are ignoring almost everything about engineering. I am no different for topics outside my areas of expertise. One can be pretty sure so, that engineers developing certain products know pretts well what they are doing. Within then constraints of course, those range from cost to weight to size to design and hard and physical ones. And every public engineering screw up, real ones, not the perceived ones, are simply the exceptions proofing the rule.

Good to hear an engineer chime in. I'm an IT guy not an engineer. Having been involved in the firearms game for a very long time (50 years) I do know the slow uptake on composite frame materials was largely due to consumer demand (don't want no cheap plastic pistol), and political (fear and ignorance about what can and cannot be seen in metal detectors) and traditionalist views in the management of the companies. Once these hurdles were overcome, now most new firearms (at least handguns) are made of composites and the stocks of most long guns are also a composite material vs. wood.

Interesting perspective from an engineer. Thanks for your insight.

 

[hef19898]

Temperature behaviour is a very important. Metalic parts expend and retract more than plasitcs and composites. To offset that, they need more meat, and weight. They are cheaper so. Especially in precision part like lenses, that is important.

Working from the top of my head, I am only remotely involved in those topics, maintainability, logistics and spare parts are more my immediate areas of expertice. That being said, even for those aspects, steel or composite make a huge difference.

 

[Nimi]

I didn't want to hijack Ronald's thread asking about lightweight / lighter weight equipment for photography so I'll start a new thread.

Other than tradition and most of us being somewhat traditionalists, is there a good reason why lens manufacturers shy away from using modern lightweight composite materials for lens barrels? I can see huge advantages with little downsides and wanted to hear your opinions and thoughts
Pro as I see it:
Lighter Weight than steel or aluminum
Highly Durable (Glock pistols and military M4 rifles take far more abuse than any camera ever will and they hold up to that abuse in specular fashion.)
High tensile, impact, and shear strength
resists warpage and expansion due to temp changes
Not as "cold" to the hands during cold weather
It will not dent if dropped (scratch but not dent)

Cons as I see it:
Not traditional, photographers say "Plastic" without giving it further consideration
Probably does not save much money as these materials are as expensive to make as it is to make equal part from aluminum or steel.
Not sure exact weight savings, what percent of a lens' weight is the barrel vs. the glass?


What are your thoughts?
Jeff

I believe the Viltrox 20/2.8 is all polycarbonate.

 

[hef19898]

Good to hear an engineer chime in. I'm an IT guy not an engineer. Having been involved in the firearms game for a very long time (50 years) I do know the slow uptake on composite frame materials was largely due to consumer demand (don't want no cheap plastic pistol), and political (fear and ignorance about what can and cannot be seen in metal detectors) and traditionalist views in the management of the companies. Once these hurdles were overcome, now most new firearms (at least handguns) are made of composites and the stocks of most long guns are also a composite material vs. wood.

Interesting perspective from an engineer. Thanks for your insight.

Welcome! One driving factor is also cost: sheet metal, in the case of weapons, is cheap but hard to get tolerances right. It is not WW2 after all. Machining from solid material, again for weapons, is easy to get tolerances right. It is expensive so (the material machined away is scrap) and comparatively heavy. In the last decades, composites, plastics and various plastic / magnesium alloys and so on, became cheaper and cheaper to produce. Now, the offer a good enougj trade off between cost, precision, weight and all the othet relevant trade offs, and are hence used more and more. Especially for non structural load bearing parts, joints and such are still mainly metalic of some kind.

I think for arms, the turning point was in the late 70s, started way earlier, with stuff like the MP-5, Glock and others. In the 80s, a lot of mass produced arms contained plastics and composites. Cameras as well, starting with the 80s I'd say (I didn't investigate at all, please bear that in mind!). Nikkor lenses started to be "plastic" with the 90s kit lenses, pro level stuff with the AF-S models. I assume Canon and others followed, more or less, the same trajectory.

 

[bleirer]

There are whole master's degrees and doctoral dissertations on material science. I'm sure the lens makers are studying every aspect of it. One thing is weight sure seems to run with f number. I guess more glass and more housing material of whatever type as lenses get faster. On the other hand some designs, like the nikon PF type lenses seem to keep weight down.

 

[jeffnles1]

Welcome! One driving factor is also cost: sheet metal, in the case of weapons, is cheap but hard to get tolerances right. It is not WW2 after all. Machining from solid material, again for weapons, is easy to get tolerances right. It is expensive so (the material machined away is scrap) and comparatively heavy. In the last decades, composites, plastics and various plastic / magnesium alloys and so on, became cheaper and cheaper to produce. Now, the offer a good enougj trade off between cost, precision, weight and all the othet relevant trade offs, and are hence used more and more. Especially for non structural load bearing parts, joints and such are still mainly metalic of some kind.

I think for arms, the turning point was in the late 70s, started way earlier, with stuff like the MP-5, Glock and others. In the 80s, a lot of mass produced arms contained plastics and composites. Cameras as well, starting with the 80s I'd say (I didn't investigate at all, please bear that in mind!). Nikkor lenses started to be "plastic" with the 90s kit lenses, pro level stuff with the AF-S models. I assume Canon and others followed, more or less, the same trajectory.

I don't want to stray too far off track of photographic gear. I've been involved in the precision target game for a very long time. I still hear guys (even young people) talking about "cheap plastic" even after the guy with the "cheap plastic" just cleaned their clock in the competition.

The only reason I brought firearms into it was thinking most people can relate to the abuse a military firearm or, any firearm, takes when being fired repeatedly. Comparatively even our most used lenses are babied and cameras are babied.

Great discussion and thanks for adding the engineering perspective to it.
Jeff

 

[jeffnles1]

There are whole master's degrees and doctoral dissertations on material science. I'm sure the lens makers are studying every aspect of it. One thing is weight sure seems to run with f number. I guess more glass and more housing material of whatever type as lenses get faster. On the other hand some designs, like the nikon PF type lenses seem to keep weight down.

agreed.
I think one other element is consumer perception. Any industry that ultimately sells product to general public consumers (that would be us) has to take into consideration if they want to be on the leading edge. I can understand the conversations over if some popular influencer started talking about cheap plastic, rolled over the lens with his/her car or tossed it out of a 10 story window to show how it broke and how that would impact sales.

Some of the "complaints" YouTubers have lodged against every major brand and model of camera border on the absurd but that is a discussion for a much different thread.

Jeff

 

[hef19898]

Materials don't care what they are used for, so bringing arm firearms wasn't really a problem. After all, Glock pioneered the use polycarbonates and such in a lot of ways.

 

[ajrmd]

There are certainly opportunities to employ alternative materials in lens making and they are slowly occurring. The use of plastics in optics and bodies is occurring and will likely continue as familiarity and experience increases. There are a number of logistical challenges in terms of R&D, capital investment, scaling, production, etc. which influences the rapidity with which these materials are incorporated into production. While weight is a consideration, given the current materials used, I don't believe that any potential savings would offset the other driving factors.

 

[ajrmd]

Materials don't care what they are used for, so bringing arm firearms wasn't really a problem. After all, Glock pioneered the use polycarbonates and such in a lot of ways.

Not to bust your lenses on this, but Glock uses Nylon 6 which is a polyamide and not a polycarbonate. Nylon 6 is made from caprolactam, where the amide ring is broken down and then polymerized into filaments which can be heated and shaped into many forms. It's been around since the 1930's and is a tough and interesting material. Polycarbonates have carbonate cores synthesized from BPA and phosphene. They have different mechanical, thermal, and other properties and are used for different applications. For example, Nylon 6 has higher tensile strength, hardness, and resistance to hydrocarbons, etc. than a typical polycarbonate.

 

[hef19898]

You see, I am no material scientist! Either way, for manufacturing, Glock was among the pioneers of using non-metalic materials. Credot were credit is due.

 

[Craig Yuill]

For a couple of years I have been using what I have dubbed the AF-P DX Nikkor “plastic fantastic” trio of lenses with my Nikon D500. The 10-20mm VR, 18-55mm VR, and 70-300mm VR lenses. They are all small, light, and surprisingly sharp. They seem to be sturdy enough, but certainly lack the mechanical refinement and weather sealing found in higher-priced lenses. Still, they are good lenses.

I must say, however, that I do admire the construction of older F-mount lenses. I have kept a Nikkor 300mm f/4.5 ED-IF lens largely because it is built like a tank, and I love the feel of the lens and its moving parts. Metal certainly has a “feel” to it.

I can see lenses having plastic lens barrels with other parts being made out of metal where needed. I think a number of manufacturers do this already.

 

[hef19898]

Is your 300mm by any chance an Ai-S? I have the same, incredible lens. Sharp, renders very nicely, comaparatively light and small. And the manual focus is something else, smooth as silk and precise. Those high tier Ai-S lenses are master pieces of precision mechanics!

 

[Craig Yuill]

Is your 300mm by any chance an Ai-S? I have the same, incredible lens. Sharp, renders very nicely, comaparatively light and small. And the manual focus is something else, smooth as silk and precise. Those high tier Ai-S lenses are master pieces of precision mechanics!

I believe that my copy is an AI-S lens. My copy needs to be stopped down to f/5.6 before it becomes truly sharp, although has some light falloff towards the corners. It is best at f/8. The AF Nikkor 300mm f/4 lens that followed it was, IMO, better optically. I rented it twice, and was quite impressed by it. Another lens that I rented was the AF-S Nikkor 300mm f/4 PF lens, which was even better, IMO. And so petite. A brilliant lens!

 

[Lee R]

I’d be all for a Sereebo 600mm.

Metal feels nice, but I’d rather have a tough composite.

I was military and nearly everything is composites now for that reason, shipping containers of all shapes and sizes, rifle stocks/forearms. A lot of aircraft stuff. Some are almost all composites now.

Actually the only thing I remember breaking was the night vision mount/bracket on my helmet, which was magnesium.

I’ve also seen in person a composite helmet after someone was shot in the head with an AK at close range. Helmet stopped the round and he had a good lump on his head, but I remember my grandfathers metal helmet which we still have, which has a whole through the front and back where a round skimmed the top of his head and literally ricocheted of his skull. Sometimes “plastic” is better.