3D print and build a 164mm f/2.5 lens for less than $15
petapixel.com
petapixel.com
I do some optics design, albeit not photographic lenses. But a f/2.5 lens is not considered to be an easy design problem.
> The only parts of the lens that can’t be 3D printed are the
> glass optics, and for this Steele used Surplus Shed to
> acquire achromatic (two-part) lenses.Everything else? Sure, nice job, but not exactly surprising.
In 3D printing, "print" generally refers to "most of the device, except those components that one versed in the field would recognized as being composed of materials not suitable for printing".
Though I do agree with you, many people who do 3D printing would not find the title misleading.
Where did you hear this? I probably see people use "glass" to refer to lenses as often as I see "lens."
https://www.google.com/search?q=photography+lens
You'll see not a single glass lens by itself, but rather every image will be of an assembly containing optical lens intended for mounting to a camera.
Also, enter any photography store and ask to see the lenses. You'll not be presented with discrete glass, but rather with assemblies containing glass intended for mounting to a camera.
Perhaps in the eyeglass industry the term "lens" refers to the glass itself as a discrete component, but not in photography.
That said, I have cnc'd a piece of acrylic, polished it, then used it to make a silicone mold and used that to make an epoxy lens.
One of the other commenters has highlighted that the lenses in question are part of this telescope kit – https://www.surplusshed.com/pages/item/T1686.html – which is indeed consistent with a reasonably good on-axis or paraxial design but with poor off-axis performance (like most telescopes). I presume these are two apochromatic doublets [1] but it's a bit hard to see.
The spherical lense creates a sphere of field of focus. The best way to correct for this is to have a spherical sensor.
Canon and Sony have indeed been working on curved sensor manufacturing, but it seems like a moonshot.
[0] https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.37...
Link points to here: https://www.surplusshed.com, perhaps he bought a telescope lens?
(Part 2: Goes into math) https://www.youtube.com/watch?v=ADtw6cxEK28
(Part 1: Shows CNCing / usage) https://www.youtube.com/watch?v=ZW2lj0KjyT8
That said, a hobbyist level CNC will not be able to make a functional lens. Tolerances are way too high. Maybe it'll be good enough for focusing light and burning holes in paper, but it's not going to be remotely close to photography level.
The amount of stuff I've printed with it, km's and km's of filament and the little beast still keeps squirting out molten plastic. Last time I looked at the stats, 91 days print time, 6355m of filament.
One of the best tool purchases in the shed ever. Really stoked with it.
What kind of printer do you have and what did it cost?
But I agree that the real world uses of 3D printers are endless. Although often you need to know how to use CAD.
That’s like saying owning a computer without basic programming knowledge seems pointless.
Obviously 3D printers are useful even if you never create or modify 3D models.
What the OP however refers to is the "rapid prototyping" that 3D printers unlocked for masses. If You learn even some basic modelling (e.g. few primitives in OpenSCAD for programmers), it's trivial to do test fits and whatever gigs You need.
I haven't realized it myself until some months ago I needed a small funnel for a bottle. After some thinking I realized it's much easier/faster to throw together a difference of two cones and two cylinders in OpenSCAD in about 10min and print it in maybe another 20 than spend the time looking around stores to find some close compromise.
Obviously there have been some successful computers where users don't modify their files, like mp3 players, but those are much cheaper and more user friendly than general purpose computers.
I found a nice looking bracket shaped specifically for my Bamix stick blender that someone else had designed, saved me some trial and error and time and filament.
I found someone else's design for a Makita LXT battery fitting that I used as the base to prototype the inverse: I wanted a dummy battery shape that I could mount to the wall in order to hang my vacuum cleaner from it.
I'm glad I can do some basic CAD / am willing to learn, but I've definitely got some use out of it with only a slicer. And then there are the people who only want trinkets anyway.
Those two projects made me realize that 3d printing can be a full time fun hobby for exploring all those things it would be too hard to machine in a garage.
OpenSCAD is fine for what it does and I do use it a lot for very simple stuff. ImplicitCAD is another interesting project in that space that has fillet unions.
FreeCAD would be great if the Interface wouldn't be so janky. I give it a try every now and then, but never really get over the re-learning aspect.
So, I am still stuck with Fusion360 running in a VM on my otherwise FLOSS-only system :-/
These days I find designing a part relaxing, similar to the feeling of writing code for a personal project.
Apparently Fusion 360 is also free for hobbyists, I’m guessing that it’s a bit easier to learn than FreeCAD.
(I realize that designing your own parts isn’t practical for most folks but I think HN is a good audience for this.)
I’ve been meaning to learn FreeCAD or one of the others because the parametric modeling seems useful, but Blender has been good enough for my purposes so far - mostly adapters for tool vacuum ports, and other little things around the house and workshop.
Similarly, all my shelf brackets are 3d printed now. THe thing that holds up my custom LED light is 3d printed. Some of the art I have around the house is printed...
Here's a 3D printed camera with a lens that really was 3D printed and polished:
https://formlabs.com/blog/creating-camera-lenses-with-stereo...
f/2.5?!
Heh - this is a remarkable feat of intentional engineering; but it’s absolutely useless as a functional camera.
Also, a manual 165mm lens on full frame? I'm sure it could be great for interesting portraits, but street photography?
Good luck using a 160mm lens for street photography, especially given only the center 10% is somewhat sharp
Vintage lenses are slower but at least you can take good photos with them, it's like comparing a diy car based on a lawnmower and a ford focus
Now that might be a bit unusual choice of lens, but news photographers around the world rely on their zoom lenses that won’t open up more than f2.8.
And for a prime lens in this long focal length, f2.5 is still quite okay, Canon’s EF135mm opens up until 2 that’s only 2/3rd of a stop faster.
Really fast lenses get attention because they are the most expensive, and shallow depth-of-field has been in fashion… I think in part because it gave photographers a way to distinguish themselves from smartphone wielding amateurs. I predict this is on the way out now that portrait mode fakes this look! But a super fast lens is in no way necessary for taking great pictures.
I’m sure there’s plenty of valid criticisms for this project but this one does not convince me :) Personally I wonder more from an ecological point of view, i.e. why use all these resources when there’s plenty of unused lenses on the second hand market. But then again the Open Source aspect is commendable.
Also, I think the source link might be better: https://www.pixelsandprisms.com/3d-printed-lens/ (more photos, no ads to block, and not sure what OP adds).
This one. I believe all lenses are blurry in the corners to some extent, but it's not usually that bad.
A low number (f/1.6 is fairly low. f22 is fairly high) means that only the object you focused on will be sharp and anything nearer or further away will become blurry. This is great for portaits for example as it draws attention to the person.
(f is the aperture and also affects the amount of light. You can shoot with a lower shutter speed if you have a wide aperture/low f number)
The "mm" number is the amount you're zoomed in. Wide is a low number, telephoto from a distance is a high number.
But blur can come from other things. Cheap lenses, unsteady hands or moving subjects. Depth of field is just one type of blur.
And at the end of all of that you are not going to make anything that has micron or even thousandths level precision. For something like a lens, machined metal and at a minimum injection moulding is needed. It would be as if I said I could produce a gauge block to measure 10mm for a fraction of the cost. But for that cost savings my precision will be unusable when my block is not flat and is 9.956 mm which in 3d printing would be very close but in machinist land is off by a mile. Lens casings and aliignment need similar precision.
The automated microscopes I build are mostly 3d printed parts. The precision doesn't matter much- I always have to add additional hardware to adjust the precise positioning (typically screws going through 3d printed threads).
But you are right there are definitely other methods which work faster and cheaper and ten thou is a typical target for a good machinist.
The inventor, Steele, describes a cardboard jig for calibrating the parametric design. It sounds almost as important as the final lens casing itself.
This all makes me want to buy a 3D printer.
Still, pretty impressive for a DIY project. The lack of clarity might be taken positively as an interesting lens characteristics; might even attract some camera enthusiasts to use this.
Sadly . . .
> The only parts of the lens that can’t be 3D printed are the glass optics
It's surprisingly easy to 3D print the shape of a lens and polish by hand. I made a working telescope this way with a 3D-printed body and two cast epoxy lenses. As an added bonus, you can easily make aspherical lenses this way.
If you coat the surface with silver you can also make mirrors, but the polishing requirements for this are a lot more difficult. My attempts at a 3D-printed telescope mirror have very bad image quality compared to the excellent results from the lenses.
Would be a much interesting article than the one at the link (not your link, the original HN clickbaity link)
[0]https://blog.prusa3d.com/3d-printed-lens-and-other-transpare...
That might work if you only care about "clear", but unless you exactly match the optical properties of the resin and (printed) filament, it will be pretty useless as an optical device.
Chemically depositing silver with the old-fashioned immersion setup is also very tricky as the reaction is quite temperamental. I recommend the two-part spray process if you want to try silvering a telescope mirror.
just out of curiosity what's the "two-part spray process"?
It's still ultimately a silver nitrate reduction reaction, but it's extremely consistent. I tried reproducing the classic silver nitrate/glucose/sodium hydroxide/ammonia silvering baths astronomers used before the modern switch to aluminum vacuum coatings, and my success rate was only about one in five attempts. It's much more difficult to execute than the typical silver nitrate demonstrations where someone silvers the inside of a glass flask because you need the silver to produce a perfectly even layer on the outside surface of the glass for a telescope. The spray reaction has worked for me every time.
I think the title should read "print a housing for $15 glass to make a 164mm lens" or something like that to indicate that it's not the actual lens elements that they're printing, but of course it wouldn't be clickbait and many people including me wouldn't have clicked on it.
I fear I already know the answer to that, and I fear I al$o know wh¥.
Which is not to say that lenses are not overpriced, but the fact that you can theoretically 3d print your own... anything (gun? Car parts? Doorknobs?) doesn't imply anything can or should happen to the price of a much more functionally complete product.
You can buy a ton of ok lenses in the $100-300 range, as there are several vendors in that range from Asia. Some of them can be really a steal. But overall you get the quality you pay for. Look what the lenses of the big camera companies offer, both optically and from features like AF and IS, and you see why 3D printing won't just turn the market upside down.
As an enthusiast, I find the tinkering possibilities opened up by 3D printing highly interesting though.
We had better lenses than this in the early 1900s already