My most important lenses are made of plastic

[Frankly Unsharp]

Hello,
And well guessed, these lenses are the ones I carry on my nose all day, and I couldn't manage without them. For many years now the lenses in spectacles have been made of plastic, constantly developing with thinner lenses and better coatings as a goal.
Maybe I'm ignorant or just stupid, but why not use this technology in for example MF lenses (yes, Holga has them), where the big chunks of glass ads to the already heavy construction. Oh yes, most of these lenses are not made anymore, but how about the dark (digital) side AF-zooms? A quick look at a Canon Zoom Lens 55-250 gives You the impression of glass, but is it really? Everything else seems to be plastic.
Information, please!

 

[benjiboy]

So are mine, but "plastic" is is a great over simplification, there are so many diferent sophisticated polymers these days that are suitable for anything from milk crates, watch cases to guns etc.
I assume you mean the lens barrels not the lens elements.

 

[narsuitus]

Specifically, which lenses do you consider to be your most important?

 

[Chan Tran]

So are mine, but "plastic" is is a great over simplification, there are so many diferent sophisticated polymers these days that are suitable for anything from milk crates, watch cases to guns etc.
I assume you mean the lens barrels not the lens elements.

For me I mean the lens element. The lenses I am talking about are the ones I am wearing right now and they are the most important.

 

[benjiboy]

For me I mean the lens element. The lenses I am talking about are the ones I am wearing right now and they are the most important.

Mine too Chan, they are Pentax Tailor Made Varifocals.

 

[erikg]

Aside from the original equipment that I was born with, my most important lenses are also varifocal plastics and I'm very happy about that.

 

[Frankly Unsharp]

For me I mean the lens element. The lenses I am talking about are the ones I am wearing right now and they are the most important.

Yes, exactly! And mine were made by Zeiss (Zeiss Single Vision) Very interesting, Zeiss and plastic lenses, hmm...

 

[summicron1]

Hello,
And well guessed, these lenses are the ones I carry on my nose all day, and I couldn't manage without them. For many years now the lenses in spectacles have been made of plastic, constantly developing with thinner lenses and better coatings as a goal.
Maybe I'm ignorant or just stupid, but why not use this technology in for example MF lenses (yes, Holga has them), where the big chunks of glass ads to the already heavy construction. Oh yes, most of these lenses are not made anymore, but how about the dark (digital) side AF-zooms? A quick look at a Canon Zoom Lens 55-250 gives You the impression of glass, but is it really? Everything else seems to be plastic.
Information, please!

Yu can bet if plastic worked in photographic lenses it would be used, and I think it is in some cases although I can't name any right off.

i suspect that the demands of photographic lenses are much higher than for the lenses you balance on your nose. Also the job they do is vastly different. Correcting vision through your eyeballs probably is not as difficult as creating an image on film, since eyeglasses are only one part of a complex optical system (your eyeball) while the lens on a camera must be the entire optical system.

For this reason, high quality optical glass is still used in fine lenses. Optical polymers (plastic) are good enough for the job that eyeglass lenses do.

 

[gone]

I suspect that the plastic, or polycarbonate, lenses of eyeglasses would not hold up well over time on a camera lens. I know that the coatings on my glasses are usually toast in a year or two. They can't be baked on at high temps like glass or they would melt. Some companies have made inner lens elements out of plastic, probably because they would not be exposed to the rough handling of an outer lens.

 

[Sirius Glass]

The Zeiss Hasselblad lenses have metal tubes and parts, not plastic. If you want exercise carry the 50mm, 80mm, 150mm, 250mm lenses, 2X extender, close up tubes, and multiple film backs in a pack for a day. Arm exercised include carrying a non-carbon fiber, non aluminum metal tripod in your hands.

 

[Nodda Duma]

Plastic lenses are very good for two things:

1) Incorporating additional mechanical features
2) Very high volume production of low-quality lenses


Unfortunately, the best shape for a (swappable) camera lens is round. So incorporating mechanical "other things" into a molded glass will just drive the size up.

The requirements for image quality are higher than molded plastic lenses typically bear. You could do it, but only the center 2/3 of the plastic lens diameter would be of high enough quality to be useable. So the camera lens would be larger diameter. I usually see them in eyepieces, which don't have near the resolution requirement of a photo objective.

The cost of the molds for plastic optics start at $100k. You aren't going to sink that much money into, say, a 1000-lens production run. You'll do that if you sell millions of the lenses. I don't think the MF market would bear those numbers. 35mm format yes, but not MF.


Cameras that did use plastic optics are the single-use film cameras. If you take one of the Kodak examples apart (do they still make them?) you'll find that there's a single clear plastic piece for the objective lens (a landscape lens type design), viewfinder, and the film counter cover. Very cheap.



So forget about molded plastic for SLR objectives. Molded glass lenses, however, are perfectly acceptable for precision optic use and I'd bet my salary that the mass producers who advertise aspheres are molding those aspheric lens elements to drive down the cost.


-Jason

 

[Thomas Bertilsson]

I think that eyeglasses are meant to last a year or two. Most camera lenses need to last for decades.

Eye glasses are necessary. Cameras are a luxury.

 

[cramej]

Don't forget that lots of 35mm(and all the related formats) lenses were/are made with polycarbonate lenses - many with great success. Of course not every element of the lens is poly but often times more than one element is. It could translate to MF lenses, but it's a different crowd and they probably wouldn't sell very well.

 

[Newt_on_Swings]

Instant camera lenses and view finders are plastic. I actually just ordered a pair of new glasses online for $15 which is incredible (though I have yet to get them). The updated replacement lenses I got for my current glasses in February at the shop were $100, what a mark up on only plastic. But my sunglasses are still glass lenses though, you still can't beat them for clarity and scratch resistance. If I could get glass lenses for my glasses (impossible since they are rimless and are held in by to small holes) I would.

 

[Slixtiesix]

My "glasses" are made from plastic either. They were made by Rodenstock and I´m very pleased with the "image quality". However, plastic lenses are extremely prone to scratching. I only wear mine when driving or going to the cinema, so they still look good, but I doubt they would stand what some of my friends have experienced with their glass glasses. Hitting hard objects, scratching along surfaces, being dropped on concrete. I´m quite impressed what some glass can stand!

 

[Xmas]

Hello,
And well guessed, these lenses are the ones I carry on my nose all day, and I couldn't manage without them. For many years now the lenses in spectacles have been made of plastic, constantly developing with thinner lenses and better coatings as a goal.
Maybe I'm ignorant or just stupid, but why not use this technology in for example MF lenses (yes, Holga has them), where the big chunks of glass ads to the already heavy construction. Oh yes, most of these lenses are not made anymore, but how about the dark (digital) side AF-zooms? A quick look at a Canon Zoom Lens 55-250 gives You the impression of glass, but is it really? Everything else seems to be plastic.
Information, please!

They have done and can do.

If you drop a DSLR with hood reversed it is not good.

They do use high precision molds with low melting point high refractive index glasses for aspherics.

But the tolerances for even simple lenses are very high and glass is cheap cept when it shatters and is in your eye.

 

[pdeeh]

Don't forget that lots of 35mm(and all the related formats) lenses were/are made with polycarbonate lenses - many with great success. Of course not every element of the lens is poly but often times more than one element is. .

Couple of questions:

What's a "related format"?

And could you give a few examples of brands/manufacturers, and even better a few examples of common (successful) lenses using such polycarbonate elements?

 

[AgX]

Plastic lenses are very good for two things:

1) Incorporating additional mechanical features

What do you mean by that?

 

[Frankly Unsharp]

The Zeiss Hasselblad lenses have metal tubes and parts, not plastic. If you want exercise carry the 50mm, 80mm, 150mm, 250mm lenses, 2X extender, close up tubes, and multiple film backs in a pack for a day. Arm exercised include carrying a non-carbon fiber, non aluminum metal tripod in your hands.[QUOTE

You should get a motorized vehicle of some sort for all Your gear, preferably an off-road for climbing the hills....

 

[Xmas]

we have lapsed into my daddy is bigger than yours again.

Polycarb is useful for lots of things always wear goggles.

Too low a refractive index for optical lenses or some specs eg

http://en.m.wikipedia.org/wiki/CR-39

better if you need much correction.

Thinner spec lenses better photo lenses.

The modern plastic lens barrels and cladding is uber cheap compared with high precision molds and CNC milling of aluminium or brass as well as lighter in weight.

My RB67 is heavier than a blad and the negs are bigger.

 

[erikg]

What do you mean by that?

Perhaps something like what Polaroid did with the Spectra camera lens. It was a lima bean shape that allowed it to focus quickly with a quick twisting shift.

 

[AgX]

Eric, I totally forgot about that focusing system.

 

[cramej]

Couple of questions:

What's a "related format"?

And could you give a few examples of brands/manufacturers, and even better a few examples of common (successful) lenses using such polycarbonate elements?

Related formats would be FX, DX, APS-c and it's variants, Micro4/3, and whatever the newer formats by the big 5 are coming out with.

http://www.nikon.com/about/technology/rd/core/optics/aspherical_lenses_e/index.htm

Nikon uses 'resin' in a lot of the aspherical elements. Any lenses on their website that say 'hybrid aspherical lens' are glass molded with resin. Sony alludes to this as well. Canon is not so forthcoming about it's lens construction. Pentax also uses them. I use Nikon so I know more about them then the others.

18-55 vr
14 f2.8
18-135 ED
17-35 f2.8
24-85 f2.8-4

There are a lot more lenses to go through that were not in the list I checked. Don't downplay the 18-55 and 18-135 - they are excellent lenses. The 18-55 is a sleeper and much better than the 18-70 it replaced.

 

[Sirius Glass]

[

The Zeiss Hasselblad lenses have metal tubes and parts, not plastic. If you want exercise carry the 50mm, 80mm, 150mm, 250mm lenses, 2X extender, close up tubes, and multiple film backs in a pack for a day. Arm exercised include carrying a non-carbon fiber, non aluminum metal tripod in your hands.

You should get a motorized vehicle of some sort for all Your gear, preferably an off-road for climbing the hills....

Like me second vehicle?

 

[flavio81]

Hello,
And well guessed, these lenses are the ones I carry on my nose all day, and I couldn't manage without them. For many years now the lenses in spectacles have been made of plastic, constantly developing with thinner lenses and better coatings as a goal.
Maybe I'm ignorant or just stupid, but why not use this technology in for example MF lenses (yes, Holga has them), where the big chunks of glass ads to the already heavy construction. Oh yes, most of these lenses are not made anymore, but how about the dark (digital) side AF-zooms? A quick look at a Canon Zoom Lens 55-250 gives You the impression of glass, but is it really? Everything else seems to be plastic.
Information, please!

Surprised nobody commented regarding Canon EF lenses.

Sometimes lens elements are made of a special resin. In the case of some (usually cheaper) Canon EF lenses, a resin lens molded into an aspheric shape can help either (a) increase performance over a conventional (spherical) lens or (b) bring down the cost of the lens while keeping performance high. You can be sure the rest of the lens elements are made of glass.

There are also hybrid Canon EF lens elements where an aspheric lens is made out of a conventional glass lens + a special resin "border". This was the case, for example, of the EF 22-55 lens.

Higher priced Canon EF lenses use glass-molded aspheric lenses instead of resin molded aspheric lenses.

The luxury (L) Canon EF lenses almost always use ground aspheric lenses. Which adds a lot of manufacturing cost.

Of course, all those cases assume the lens design include aspheric lenses. There are man many high performance Canon EF lenses without aspheric surfaces; mostly moderate-aperture prime lenses like the EF 85/1.8.

All in all, i wouldn't worry. Canon's optical design department is probably the best in the world, if you stick to their EF prime lenses you will always get very high performance regardless of the lens.