I've long been intrigued by the engineering in packaging that delivers the products that we use. Simple everyday stuff. I've been collecting my own recycling for a couple months and started examining some of it. I like to shoot things as I find them, something about the chance element of how it arrived to me makes it precious and needs to be preserved. It's about looking and lighting, for me that's pure photography.
One thing worth mentioning as it might not be apparent on the web: These objects are tack sharp front to back, you can see every little thread, piece of lint, fuzz, etc. Those kinds of details are interesting to me.
Tech Talk: To get these completely in focus requires several exposures, front focus, mid focus and back focus. When you change the focus, the image size changes - as you back focus the image gets smaller, at this size, around 1.5%. We used to manually adjust and resize each exposure, it's a tedious chore. Thankfully I found some software that will do it automatically, and it works well most of the time. I think that's pretty amazing that someone could write an algorithm to find the sharp detail in a series of different exposures, separate that detail from the soft areas, and then resize them to create one single sharp image.
Another tech detail about my process: I shoot with a multi-shot back. Meaning, to create a digital file it's sampled 4 times. There are 4 exposures recorded to create a single image. A brief explanation: Imagine a grid with 39 million pixels, dots. To create color information there is an RGB filter grid in front of those pixels. Imagine a square that has a red, green, blue and another green filter, each the size of one pixel, then that grid is repeated to cover the entire sensor area. When you photograph something that is predominately say, blue - the red and green pixels don't record much, if any, information. The software has to interpolate what colors those red and green pixels are based on what's being recorded around them. There is software interpolation of the color and detail, that's the way all single shot CCD chips work. With multi-shot technology that filter grid is shifted one pixel at a time so each quadrant on the grid is sampled accurately. Since these is no software interpolation of the color and detail, the digital files are much smoother and have a much higher level of detail. A problem is the subject can't move, when we're shooting everyone in the shooting area has stay completely still. With a subject like these, the slightest breeze causes movement in the subject. It can be a patient process, but I feel worth it as the detail really is incredible.
2 comments:
Question: The fine detail is really terrific (lint, texture in cardboard, etc.). I think that I understand how you assmeble these through focus images into a single image. But I also understand that this is not simple and could produce artifacts.
So here is my question: Could you get the same result by greatly reducing your aperture to increase your DOF, and then giving more exposure time to compensate? (I'm not a photographer, so this might be a stupid question with an obvious answer.)
I shot with strobes, so shutter speed doesn't really factor into the equation as I can control how much light there is by adding or subtracting power on the flash generator.
Depth of field is primarily determined by the reproduction ratio - how close the camera is to the subject. While you are correct stopping down the aperture does increase depth of field, at this camera to subject distance - reproduction ratio, the depth of field is probably 1/2 to maybe 3/4 of an inch at f/22. Stopping down further than f/22 gains some, not much, depth field but then the overall image sharpness suffers.
The only way to get the whole object in focus with one exposure would be increase the camera to subject distance, or decrease the reproduction ratio - make it smaller on the sensor, which then means larger magnification when printing, then that means loss of detail - so that's why I do it this way, shoot them close up to get maximum detail.
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