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| Extreme close up photo of the Atmel Mega328 microprocessor on an Arduino Uno development board. |
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| Macro shot of a pair of carbon resistors attached between pin 6 and 7 and the tiny breadboard that is sitting in the middle of my Adafruit protoshield. The hair betweeen the resistors is a bonus subject. Funny the things that can sneak into your shot at this magnification level. |
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| Extreme closeup of the top of a TDK piezo buzzer. |
Here's a photo of my macro electronic component photography setup.
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| A Canon 5dMK2, a 28-80 f/4-5.6 kit lens, two Smith Victor hot lights and our model - the Arduino Uno. |
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| A closer shot of the camera - notice I have all three Kenko extension tubes connected 12,20 and 36 mm. You can use none, one, some or all tubes to suit your taste. |
What you need to take high quality macro photos of your electronic projects:
1. A dSLR camera. I'm using a Canon 5dMK2, but just about any modern digital SLR will do. If your digtal SLR features a "live view" mode, macro photography will be a lot easier.
2. A lens. Any lens will do, but some are better than others. I'll discuss further below.
3. A set of Kenko extension tubes.
4. Light!
5. A tripod.
Some lenses are better than others for macro photography. Lenses that have a short minimum focal distance are much better for using with the extension tubes. Zoom lenses are also much better, as you are able to adjust your focus using the zoom AND the focus ring.
When you use extension tubes you are increasing the distance between the camera and the lens. The extension tubes are simply hollow tubes that also have contacts so the lens can maintain an electrical connection with the camera. Increasing the distance from the camera causes the focus range of the camera to shift. The camera will no longer be able to focus at long distances, but the minimum focal distance will become much shorter. A side effect of shifting the focal distance of your setup is that the depth of field, or the amount of area in focus, becomes much narrower. The more and/or bigger extension tubes you use, the more pronounced this effect becomes. The reduced depth of field will change some of the other settings and setups we use in this tutorial.
To combat the extremely narrow depth of field cause by using extension tubes, we will do several things. #1 - We will use a very small aperture when taking our photos. I shot the above photos at f/16. The smaller aperture reduces our depth of field to reasonable levels, so we can have as much of our photo in focus as possible. The good side-effect of using a small aperture is that even cheap lenses will look extremely sharp at small apertures. The reason is that only a small circle of the very middle of the lens is being used when the aperture is closed down tight. Even cheap lenses look good in the sweet spot. It is typically hard to discern between a cheap kit lens and more expensive glass at f/8 and beyond. It is only as the aperture opens up and the glass at the edges is being used will we start to see advantages from more expensive glass.
I have a few expensive lenses, but the minimum focal distance and zoom capabilities of the Canon 28-80 f/4-5.6 made it a better fit for macro photography than my 28mm f/1.8 and 85mm f/1.8 primes. Looking at the photos above, you can see how sharp the images are with the lowly Canon kit lens. I would probably have trouble getting someone to pay me $30 for that lens on eBay.
Here are the steps for taking a macro photograph of your circuit.
1. Set your subject up on a relatively low table. The sole reason for this is to make working with the camera more comfortable.
2. Blast your subject with plenty of light. Pay special attention to shadows. The light should be coming from a downward direction, in line with the camera as much as possible. If you have a ring flash (I don't) that is even better.
3. Use your lens with the extension to determine how many tubes you will need to achieve the level of zoom you want.
4. Put your camera in manual focus.
5. If taking a straight down shot, you will want to make your camera perpendicular to the table surface. This will help keep everything flat and most importantly, in focus. A trick I use is to square the camera up on straight down shots - loosen the tripod so the camera can rotate freely. Drop the middle support of the tripod until the lens is touching the surface of the table squarely. With the lens resting flush on the table surface, tighten the tripod head. This will ensure the camera is square to your work for the rest of your session and is much easier than using bubble level. See the video below to watch me square my camera up.
6. Turn your live view on and put your zoom in approximately the middle of it's range. Adjust the height of your tripod until you are somewhat close to being in focus. Use your zoom ring to bring the focus in clear, then use your focus ring to get the focus perfect.
7. Set your aperture at f/16. ISO at 400 or less. Shutter speed should be set for a proper exposure, or just use Av mode and let your camera figure it out.
8. Double check your lighting and position of your subject and take the shot. Since you are using a small aperture, you will probably have a long shutter time. When you press the shutter release on your camera, you will cause it to shake which can introduce motion blur into the picture. There are several ways to combat this. I usually just put my camera in delay shooting mode, where when I press the shutter the camera doesn't take the shot until two seconds later. This give the camera time to quite moving before the exposure. Alternatively, you can use a remote trigger to activate the shutter. You can also use mirror lockup mode. In a normal shot, when you hit the shutter button, the mirror swing up out of the way, the aperture adjusts to the prescribed setting, then the shutter opens and closes. The mirror slapping back can introduce shake, hence 'mirror lockup mode'. In mirror lockup mode, the mirror will swing back on the first press of the shutter button, then the shot will be taken on the next press. This might be overkill, but it's good to know about in general.
A full set of Kenko extension tubes is going to run you around $170. You can go cheaper and get an off brand, but make sure the electrical contacts are compatible with your camera system so you will still have control of your lens' aperture setting. If you don't need extreme closeups, you may be able to get by with the above setup and no extension tubes, depending on your lens.
Lens manufacturers do make lenses with very short minimum focal lengths if you have the need and funds to purchase a dedicated macro lens. Canon makes a fine macro lens, the 100mm f/2.8, but it will set you back a little over $500. The 100mm macro lens has a minimum focusing distance of 1 foot, compared to the 85mm f1.8 lens that has a minimum focusing distance of close to 3 feet. For my money and convenience, the results I get from the kit lens are good enough that I don't feel the urge to spend more money on a dedicated macro lens.
One final tip - remember that lenses tend to perform best in the mid range of all settings. With a zoom, the middle range of the zoom will be sharpest, while the extreme wide angle and extreme telephoto will be more blurry and have more perspective distortion. The same applies to the aperture setting - just about all lenses perform best at f/8 or f/11. Most times creative wants and technical needs take us away from the 'sweet spot' of our equipment, but it's a good thing to keep in the back of your mind on the rare occasions you have a choice. It just so happens, when you are setup on a tripod, taking a photo of an inanimate object, with studio lighting - you're range of choices is almost limitless. So you might as well go with the settings that let your equipment perform at it's peak.
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| Arduino UNO logos. |
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| 5 common LED's mounted on a breadboarded project I build recently on the Arduino UNO. |
