Macro photographyI needed to a way to take some very detailed shots of some of my glue test results. My old Canon Pro1 has a "super macro mode", but I found that even this macro mode couldn't capture the kind of detail I could see by holding an old camera lens up to the subject. So I had the idea of trying to put the old camera lens in front of my digital camera as a magnifier.
It consists of a small piece of plywood, screwed to the tripod mount of the camera. On the front is a block of wood with a 1" hole to fit a f/2.8 38 mm lens from an old non-zoom point-and-shoot 35 mm camera. I wrapped a bit of electrical tape around this lens to make it fit snugly in a 1" hole. The block it's in is attached to the plywood base with just one screw from the bottom. That way I can swivel the lens side-to-side to help align it. There is a wood shim under the block, which I used to get the vertical alignment with my camera's lens barrel just right. Without proper alignment, it's impossible to get the whole frame into focus.
I mounted the lens "backwards" so that what used to be the film side faces the subject. The reason for doing this is that the lens is optimized for the near field on the film side, and for far field on the subject side. When used for macro photography like this, the subject is the near field and the far field is what is then projected into the camera's lens. The digital camera is also optimized for far field on the subject side, so it all works out. It's common to flip the lens this way when doing macro photography. I used to think this was hocus-pocus, but flipping the lens to make the film side face the subject really did improve edge to edge sharpness - that is, as long as my subject is flat.
With the magnification from the 38 mm camera lens, the maximum area I can cover is a circle the size of a penny - 19 mm in diameter. Typically, though, I zoom the zoom lens in a 4x. At that zoom level, I get an image that is 1 cm across full frame, with no vignetting. Its still possible to get sharp photos hand held at that zoom level. The photo at left was taken hand-held. The key is to support your hand on the table at the same time and lots of light.
Photos I took with the above setup. Most of these were taken freehand
The catch is, just pushing the shutter button moves the camera around a little, so ideally, I'd have some sort of cable release for the camera. I couldn't use the camera's self timer because in self-timer mode, the camera focuses at the time the shutter button is pushed. Removing my hands from the camera causes enough movement to throw the image out of focus. I contemplated figuring out if I could operate the camera over USB, but that would require installing the awful software that comes with the camera and having a computer hooked up whenever I'm taking macro photos. I found a better solution - put the camera in "macro" mode, and then just tap the shutter button all the way through. Not a half-way press for pre-focus and then through press, but a single tap fully down. With the increased shutter lag, and a simple sturdy stand, the camera shake has settled by the time the camera is ready to take its picture.
The image is one millimeter wide, and the large dots are part of a half-tone line. They are 0.25 mm apart. I can barely see that these are individual dots with the naked eye. Each pixel of this image is two microns. The pixels are a bit fuzzy, but I'm pretty sure the smallest of the black toner particles are about two pixels in size. Two pixels would be four microns. Airborne particulate less than 5 microns in size doesn't get filtered out by the nose and airways and can get deep into the lungs. Of course, the toner is bonded to the paper, but I'm sure some of it gets airborne. This why photocopiers and laser printer particle emissions are considered a minor health hazard these days. Something to consider if you refill your toner cartridges from a bottle! See also: ![]() ![]() tripods
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