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Macro Lens from a Pringles Can
isharq writes "In a cool little feat of extremely low-tech hardware hacking, Photocritic has created a macro lens out of a Pringles can. According to the article: "with less than £1 worth of equipment, a little bit of sweat and tears, you can build yourself a surprisingly good macro lens". The results are astonishing."
He built an extension tube from a Pringles can and stuck a Canon lens on the front. This is not "building a lens".
"I'd rather be a lightning rod than a seismometer." -Ken Kesey
What he really built was an extension tube to allow an ordinary
lens to focus closer.
http://www.networkmirror.com/AodpyYLsgUIgSIiH/www. photocritic.org/2005/macro-photography-on-a-budget /index.html
"I'd rather be a lightning rod than a seismometer." -Ken Kesey
http://www.photocritic.org.nyud.net:8090/2005/macr o-photography-on-a-budget/
Most lenses are designed to focus on things in the FAR range - ~10+ feet. Macro lenses can focus on things very close or very small - in the 1' range.
So if you plan on shooting yet another flower and calling it 'art', you need a macro lens.
Note that many recent digitals offer moderate macro functions and do not require a macro lens.
A macro lens is capable of taking pictures of things in much more detail than a normal lens. Think of a steel countertop at a moderate distance it would look much like an ordinary camera picture of it would, but if you look a littlem ore carefully even from a few feet away you can usually see scratches in the surface. A macro lens allows you to focus closer than the usual minimum focal distance so you can capture that detail. Normally you'd only be able to get so close and then it'd just get blurry instead of clearer macro lenses are designed to overcome that limitation.
http://www.photocritic.org.nyud.net:8090/2005/macr o-photography-on-a-budget/
"Programming is like sex: one mistake and you have to support it for the rest of your life."
Focusing distance is not sufficient to qualify a lens as a macro. There are close focusing lenses that are not macro, and there are macro lenses with long focal lengths that don't focus particularly close.
A true "macro" lens is defined as a lens that allows for at least 1:1 reproduction of the subject image on the recording media. For the sake of simplicity, we'll talk film. If you photograph an object that is 1/2" across, and the resulting recorded image on the film is also 1/2" in size, you're shooting macro. A "macro lens" is one that is capable of rendering at least this 1:1 reproduction.
Unfortunately, many camera/lens manufacturer have abused the term to mean "focuses at a (slightly) closer distance than a normal lens at an identical focal length, so that when printed to standard 4x6 the image is life-size." This, of course, is regardless of the reproduction ratio of the lens. A rather silly definition, really, since any reasonable frame at any magnification can be cropped and enlarged to "life size" up to a point before quality degrades enough to become unworkable.
At 3 A.M. you can see people's auras; at five you can see their contrails...
What this guy built is an extension ring, not a macro lens. He used an existing lens, he chose non-macro lens, a macro lens would provide more precise focusing and flat focal plane but otherwise would work the same.
What he built is called extension ring, it fits between the camera and the lens and allows extremely close focusing of any lens. Extension rings go for $20-$40, sometimes you can find them used for less, or you can by a set of 3 for around $100. Factory-made rings usually preserve automatic functions of the lens, at least aperture control, sometimes even autofocus. They are usually much shorter than the pringles can, anywhere from 9mm to 45mm (and you can stack them).
So this little contraption does save you some bucks, just not as much as you might have hoped if you read the title and priced a macro lens.
A very nice way to do macro photography is to place that 50 mm (or similar) lens reversed in front of your lens. You can buy a reversing ring for the purpose. It is easy to do if you only have threads for the reversing ring on your camera (many point and shoot digital don't). Just zoom in (to minimize vignetting) and stop down the lens you are mounting the (wide open) normal lens on.
A foot away is just tremendous distance for a modern mid-priced digital camera. I have a Minolta-Konica Dimage Z5 whose "super macro" mode, while somewhat depth-of-field challenged, can take pictures within a centimeter of the lens. That's on a camera with an image-stabilized 12x optical zoom, too, so it's not like it's the intended strong point of the model. IIRC there's a slightly more recent Canon, also with a longer-than-normal optical zoom, that can take snaps of stuff that's essentially touching the face of the lens.
That's on your $500-USD tier of cameras. Granted, the DOF is not perfect, and I'm sure it's less than a flat field, but the newest midlevel consumer digicams are lots better than a reflective Pringles can...
"Fundamentalism" isn't about divine morality. It's about human authority.