Saturday, June 12, 2010

How to get close. Really Close!

A nasty hairball?



Nope! Actually a 10pt comma...




Last week a friend of mine asked which macro lens to get for his Nikon D50, the same camera I shoot with. My knee-jerk answer was the non VR version of Nikon's 105mm, which you can find used for cheap. This now discontinued lens was solidly built, razor sharp, and due to its fast aperture (2.8) can double duty as a fantastic portrait lens. I have the Vibration Reduction version, and use it for every possible shot. These lenses will spoil you in the sharpness department. "Macro", in photo-geek terms, means 1:1 magnification. The size of the object you're shooting is the same in real-life and on your capture medium (film/sensor). OK that made no sense to me either! How about a scenario: You take a photo of a dime with 35mm film, and get it developed. You set the negative next to the real life dime, and both "film dime" and "real dime" are the same size. Get it? Nevermind. Here's my trusty 105VR, and a life size portrait of a dime:





But what if you want to get closer? Life size not good enough for you? Don't have $350 hanging around for a true macro lens? Try stacking! The trick here is to mount a telephoto lens on the camera, then stick another reversed lens in front of that one (face to face). Ask your local photo store to help you with a coupling setup made from a few stepping rings, or choose the ghetto route, and use a big wad of tape as shown below. I used special tape my dad bought that also seals hydraulic lines and fixes electrical wires and garden hoses, but hell, Scotch brand would work here too. Whatever you grab first, man.



Shown above is my trusty Nikon 70-300 zoom with a vintage Minolta 28mm manual focus lens stuck out front. I'm not sure how all this works, but the longer the mounted lens, and the shorter the reversed lens, the higher the magnification rate. You can figure out power of your new setup by dividing little into big. So, if fully zoomed out, my setup is 300/28, or nearly 11:1! not bad for a little tape! You have to open the aperture of the reversed lens all the way; This works best with a manual or older AF lens on front, but you can use a "G" type (no aperture ring) autofocus lens if you tape the little aperture lever (located on the mounting side) to its widest setting. Here's what our dime looks like with this setup:



Getting all of "E. Pluribus Unum" would require a 5+ shot panorama. Yes, it's not the sharpest image, but this is due to the lack of mirror lockup on the D50. The slapping of the mirror and shutter alone are enough to send your carefully composed micro photo vibrating wildly enough to give you motion sickness. The closer you get, the shallower DOF you have, and the more pronounced vibrations become. Consider this: fine focus tuning was made with my tripod's center column knob! Tightening this knob raised the center column ever so slightly, but enough to bring the image in and beyond focus. We're talking depth of field in fractions of a millimeter. Special devices called Focusing Rails are available for finer tuning of focus. These move the whole camera assembly back and forth with a knob, but we're on the cheap, remember? Try it out and let me know what you get!

No comments:

Post a Comment