Extreme Macro Photography 101
Macro Stacking - Part I - The Hardware
Monday, October 17, 2011
Many people have asked how I go about taking my stacked macro images and what type of equipment I use. Instead of repeating myself all the time I have decided to put together this little write-up. This first part will discuss the gear to get you going. In a second part I will cover my setup. And finally, the third part is about the stacking of the images and what kind of post processing I do with my images.
The Hardware.
My discussions will be limited to using digital SLR cameras. I will mainly be showing my setup and how I use it. There are many alternative methods of attaining the same results. It really only depends on your resources, whether that is financially or what type of hardware you have access to, and your imagination.
A: The camera body. I am using a Canon digital SLR. Having a camera that allows you to change the lenses is the important factor.
B: Canon FD to Canon EOS adapter. Since I am only interested in macro photography, being able to focus to infinity, and having auto focus and electronic aperture control is not important. Therefore the adapter does not require to have any glass elements or any electrical contacts. These criteria, or lack thereof, will also translate into the bellows that I am going to us.
C: I am currently using a Canon FD auto bellows. My main concern is the ability to move the rear of the bellows while keeping the front (lens end) stationary. Typically the rear end is fixed while only the front extends out to increase the magnification. I like to keep the front end out as far as possible and adjust the length of the bellows by moving the rear end to prevent the focusing rail from interfering with the subject. I also wanted the focusing rail. Not all bellows come with that either. The focusing rail allows me course movement of the camera.
I have other bellows that I use for other lenses. Nikon, Canon, Minolta, and Olympus all had bellows and bellows macro lenses. It seems the current line up of macro lenses only go to 1:1. With the only exception that I know of being the manual focus MP-E 65mm f/2.8 macro lens, which goes from 1:1 to 5:1.
D: Another set of adapters to allow me to mount the lens to the bellows. The first adapter is a Pentax M42 mount to Canon FD. That is follows by an RMS to M42 adapter. RMS is the royal microscopic society thread used on a lot of microscope objective lenses. Some camera lenses also use this thread.
E: Nikon microscope objective lens. This is a 10x lens. The length of the bellows has to match the requirements of the objective lens. In this case I need to have 150mm between the sensor plane and the base of the objective lens. Using a ruler I verified that the actual magnification I get is 10.4:1.
There are many means of getting greater than 1:1 magnification through the use of bellows, extension tubes, diopters, reversing a lens, or using high magnification macro lens. For the adventurous there are non camera lenses that can be used to attain higher magnifications. Enlarger lenses and microfiche lenses have been used in the past. These are more cost effective means, but you will be required to come up with your own way of mounting them to your camera.
F: The linear stage with micrometer is used for the fine adjustment of the camera’s position relative to the subject. Pictured above is a Newport 423 single axis linear stage with an SM-25 micrometer. The micrometer has two scales. The primary scale is graduated to 10µm (0.01mm) and the secondary scale is graduated to 1µm (0.001mm). To take pictures at 10:1 magnification with this objective lens I need to use 10µm increments to get the proper coverage for the final stacked image. My old Del-Tron linear stage with Starrett micrometer had 25.4µm (0.001” or 1 thou) graduations. That was not fine enough for this magnification.
Microscope focusing mechanisms are also used instead of a linear stage. If you can get them at a good price they might be cheaper than a linear stage and they offer easier control with their bigger knows for fine and course adjustments.
Part II.
In the next blog I will discuss the setup. This includes the camera’s settings and control, subject mounting, lighting, props/backgrounds.
Camera Setup
