Teaser! (sorry, DOF 1mm only! - no photo stacking; promise to get better one in future...)
So, you wanna do macro pictures!
Well, first thing first, you must read allot! About macro photography, about light in digital photography and about everything photography related. This is only necessary to have the "know how" during your shoot-out in order to pass all the situations like: how do I do that!
Me, my self, I started on the wrong gear: I wanted macro photography so I grabbed the first camera kit that impressed me - Nikon D5000 + Kit lens - and went learning to make macro photography. As I discovered later in the learning process, for what I wanted I needed different brand name, Canon, as it is the only maker to manufacture a true macro dedicated lens for the job, namely MPE-65. It is a macro lens for the EOS Canon bodies that start the job where all the other lenses finishes, providing a magnification 1-5 times of the subject.
But that did not change my determination in making macro photos, I learn that you can make decent pictures with the gear you have, or you can build the set-up you need.
So, based on my gear, I learned the possibility - from a Flikr member named ProDigi - Albert Tamayo - to reverse the kit objective ( 18-55mm VR) on the camera body.
Here is his set-up.
As reverse mounting goes, I needed the following adapter ring: a bayonet-to-standard filter thread adapter
AR-9 / 52mm in order to fit the filter thread of 52mm on my objective lens and the other side of the adapter ring to my camera body, obtaining something like this
Having the set-up like this create lots of difficulties.
The following describes one method by mounting a lens directly to the camera in the reversed position.
A Macro Adapter Ring is used to mount a lens in the reverse position on a camera body.
When shooting at reproduction ratios greater than 1X (life size), mounting the lens in reverse improves image quality and increases the working distance from the lens to the subject.
The AR-9 can be used with any lens having a 52mm filter thread.
For lenses having a 62mm filter thread, it is necessary to use a step down ring (62mm-52mm) .
If you mount this lens in reverse on your camera, i.e. flip it around backwards, you get an affordable and fun way to experiment with macro photography. Right off the bat, let me say that if you want to get serious about macro (close-up) photography this isn’t the best solution. There are good reasons that lenses are engineered specifically with that type of photography in mind.
The downside is of course, those specialized lenses come with a price.
Considering the price of adapter ring I highly recommend this as a starting point or way of experimenting with macro photography. A surprising secondary benefit I didn’t expect when first using this adapter were the insights it gives you into the relationships of depth of field and aperture. So lets begin.
1. Protecting the Lens
If you haven’t used one before, it will seem strange mounting your lens in reverse. Once mounted, you see some of the guts of your lens that are normally not exposed. All of the pins the lens uses to talk with the camera are visible as well as the internal glass element that moves in and out when focusing.
Unfortunately, leaving the lens on in reverse can potentially let dust inside your lens. I highly recommend you use the lens protector cap that comes with your lens to protect it while not shooting. If you plan on using the lens in reverse often, you can buy a bayonet-to-standard filter thread adapter. This lets you screw on a UV type or other filter to keep nature’s elements away from your lens.
2. You Lose the Camera’s Brain so Use Your Own
If you haven’t already deduced it, seeing that the pins are now facing out, the camera has no way of communicating with the lens electronically. What does this mean to you? You are going to lose all the cozy automatic features of your camera.
No auto-focus since there is no talking going back and forth. In fact, with the lens mounted backwards, your primary means of focusing is going to be moving the camera, which will be just inches from your subject, back and forth until the area you want sharp is in focus.
No auto aperture either. I’m guessing that many of you have always adjusted the aperture of your lenses electronically. Say good bye to that and say hello to that manual aperture ring you may have never touched before.
Remember that normally the camera keeps the aperture open so you can look through the viewfinder and see what you are taking a picture of. Just before you take a picture, it stops it down to the appropriate size. Now the camera now has no way to open the aperture for your viewfinder viewing pleasure. This leads us to the next point.
3. Depth and Field and Lighting
I found it amazing to see the depth of field effects in real time and watch them change as you stopped down the aperture. So when using the reverse adapter, as you look through the eye piece and start stopping down the lens, you will see things get really dark really fast. Unless it’s a very sunny day, twist it all the way to f/16 and you’re staring into a black square.
Depth of field becomes critical with closeup work. The greater the magnification used, the shallower your depth of field becomes. The old rule of choosing the smallest aperture possible stands true, but only to an extent. At apertures of f/22 or f/16, a loss of general image sharpness can occur through diffraction. So for maximum sharpness, a 'working aperture' of around f/8 is recommended (see table below for exceptions).
I, my self - have made a lock pin of rubber mat, I've cut in different sizes to find via various experimenting the right one that took advantage of the maximum sharpness of my lens.
Very thin depth-of-field (area of focus) – This applies to ANY macro photography, regardless of hardware choice. For this reason, it’s usually not logical to use a wide aperture as that’ll reduce your area of focus down to a few millimeters, hardly enough to render any usable detail.
It is also interesting to note that for close-up work the area of focus in front of and behind the subject becomes more or less equal rather than one third in front and two thirds behind, as with more distant subjects.
So keep this in mind when trying to make the most of your depth of field. The formula used for calculating depth of field for closeup work is as follows:
DOF = (2cf (M+l)) M2
c = circle of confusion (0.026mm for 35mm format * )
f = aperture and;
M = magnification
I lugged in my tripod and a few lighting stands but at the last second decided to shoot everything hand-held. Shooting this way can be very difficult for a couple of reasons. First, at large apertures with a nice bright image in the viewfinder, you get a very narrow DOF. The smallest shift in your camera position changes what is in focus. It’s extremely difficult to hold the camera steady enough to get consistent shots.
On the flip side of this, some of my favorite images ended up being the more abstract one with things unintentionally out of focus. If you want a sharper image without that aforementioned razor thin focal plane, you can step down the aperture, but again, you’re faced with guessing what is in focus because you can’t see what your shooting in the dark viewfinder. A tripod would be one solution. You could open the aperture, set your focus, then stop it down to take the shot. I did this a few times without the tripod and it worked out fine.
All aperture shots required me to use my flash to compensate for the loss in light.
I used it in manual mode and selected from menu the power of discharge. Using the flash on the camera is a bad idea as it usually over shoots your tiny subject and you can’t control the light direction. Thus, I've made a diffuser using an Ice cream container, cut and drilled to fit tight on my Nikon mount of lens end.
*This setup would work best in a studio environment.
So, having done that, lets work with it:
You’ll need to set your camera to Manual mode, as the camera does not recognize you having a lens attached in the body. In manual mode you can control the aperture, the shutter and the flash power output.
You have to be on very close range from your subject, so work with static objects first. The range I'm working with my set-up is between 2cm and 5 cm. It is very close! Not to mention the DOF that is sometimes less than 1mm. This pose difficulties if you want your 3D subject to have as much detail as possible. That require to take a series of pictures of the same object while I move into the subject. Latter I combine this pictures with dedicated software - I will discuss this technique in another post - and the final image will have all the "in focus area" in one picture.
More about this technique to come.
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