The latest book of my photography can now be pre-ordered here.
Monday, July 30, 2012
Friday, July 27, 2012
Two-Color (Or One-Axis) Color Systems
RESEARCH INTO COLOR motion pictures started soon after cinematography itself was invented in the late 19th century. While color photography at that time was already well-established in the laboratory and by intrepid amateurs, cinema had its own problems, notably the need to project multiple frames per second in order to give the illusion of motion.
The main method of making color photographs was suggested in 1855 by the Scottish physicist James Clerk Maxwell. By exposing three photographic plates separately through red, green, and blue filters, and then projecting those images, overlapping, through the same filters, would then produce a color image on a screen. Or the same images could be printed on paper using various colored inks.
The main problem was determining how to do the same thing with cinematography. Any method devised would have to be visually impressive, relatively inexpensive, and would have to be extremely reliable, especially during projection at the theater. Using three cameras with three color filters was out of the question, due to parallax problems, and worse was the great expense and difficulty of aligning three separate projectors.
Compromises had to be made, and one such compromise was using only two colors: some color, perhaps, is better than no color. Film stock is transparent and has two sides, and many methods were devised so that one side would be sensitive to one range of colors, with the other side being sensitive to another range of colors. The film would be developed, producing an image on both sides, which were then dyed to the appropriate colors. The film could then be projected through standard projectors with no additional equipment needed. Surprisingly, very many films were created with the two-color method, starting in 1908, becoming common in the 1920s, and this was still used until the 1950s. But few of these color films remain with us today, and many of those survivors are now only available in monochrome versions specially made for early television.
While the two-color method died out in favor of three-color cinematography, by no means should we think that these kinds of methods are completely obsolete, being only temporary solutions limited to a particular place and time in history. Instead, I think that these methods, reinvented with digital technology, are interesting in their own right and can be used by contemporary photographers for artistic purpose. My related research on imitating Autochrome, an early color photographic process with a more limited color palette than is now standard, can be found here.
The main method of making color photographs was suggested in 1855 by the Scottish physicist James Clerk Maxwell. By exposing three photographic plates separately through red, green, and blue filters, and then projecting those images, overlapping, through the same filters, would then produce a color image on a screen. Or the same images could be printed on paper using various colored inks.
The main problem was determining how to do the same thing with cinematography. Any method devised would have to be visually impressive, relatively inexpensive, and would have to be extremely reliable, especially during projection at the theater. Using three cameras with three color filters was out of the question, due to parallax problems, and worse was the great expense and difficulty of aligning three separate projectors.
Compromises had to be made, and one such compromise was using only two colors: some color, perhaps, is better than no color. Film stock is transparent and has two sides, and many methods were devised so that one side would be sensitive to one range of colors, with the other side being sensitive to another range of colors. The film would be developed, producing an image on both sides, which were then dyed to the appropriate colors. The film could then be projected through standard projectors with no additional equipment needed. Surprisingly, very many films were created with the two-color method, starting in 1908, becoming common in the 1920s, and this was still used until the 1950s. But few of these color films remain with us today, and many of those survivors are now only available in monochrome versions specially made for early television.
While the two-color method died out in favor of three-color cinematography, by no means should we think that these kinds of methods are completely obsolete, being only temporary solutions limited to a particular place and time in history. Instead, I think that these methods, reinvented with digital technology, are interesting in their own right and can be used by contemporary photographers for artistic purpose. My related research on imitating Autochrome, an early color photographic process with a more limited color palette than is now standard, can be found here.
Tuesday, July 17, 2012
At the Limit of Perception
MANY PHOTOGRAPHERS AIM FOR exceptionally clean images, low in noise, and high in dynamic range. However, extreme sensor sensitivity is rarely needed for most photographs, especially if the photographer sticks to the basic rules of photography, which include the practice of using good lighting. A good, bright primary source of light, along with perhaps fill-in lights or reflectors, are typically needed to get good photographs.
But consider this photograph of a canoe, taken about 45 minutes after sunset, on a moonless, starless night, illumined by the waning skylight, distant fireworks and lightning, and a lone incandescent lamp a hundred or more yards away:
This was an interesting scene to my eyes, but there isn’t much to see in my image — just a very faint outline of an object. You might have better luck seeing something if you click the photo twice to see it in Flickr with a dark gray background.
I took this with my camera mounted on a tripod, but because I could hardly focus at all, I set the aperture to f/8 for greater depth of field, and I didn’t use a long exposure time because I didn’t want to spend 2 hours getting my photo — one hour, perhaps, for the exposure, and one hour for dark frame subtraction. Sometimes it is inconvenient or even impossible to get a good exposure, so you have to make do with what you can get. I wanted to see how good of an image I could get at the limit of the camera’s performance.
But consider this photograph of a canoe, taken about 45 minutes after sunset, on a moonless, starless night, illumined by the waning skylight, distant fireworks and lightning, and a lone incandescent lamp a hundred or more yards away:
This was an interesting scene to my eyes, but there isn’t much to see in my image — just a very faint outline of an object. You might have better luck seeing something if you click the photo twice to see it in Flickr with a dark gray background.
I took this with my camera mounted on a tripod, but because I could hardly focus at all, I set the aperture to f/8 for greater depth of field, and I didn’t use a long exposure time because I didn’t want to spend 2 hours getting my photo — one hour, perhaps, for the exposure, and one hour for dark frame subtraction. Sometimes it is inconvenient or even impossible to get a good exposure, so you have to make do with what you can get. I wanted to see how good of an image I could get at the limit of the camera’s performance.
Wednesday, July 11, 2012
Sunday, June 17, 2012
Giving Credit...
...WHERE CREDIT is due.
Recently I wrote about landscape photography, in the article Composition, Part 2 - Composition and Subject in Landscape Photography. But I failed to mention someone who helped me out tremendously, not only by often driving me around to locations, and providing moral support and encouragement, but also by pointing out good camera positions. I owe a lot to Tina, whose photos can be found at http://snupsphotos.blogspot.com.
Recently I wrote about landscape photography, in the article Composition, Part 2 - Composition and Subject in Landscape Photography. But I failed to mention someone who helped me out tremendously, not only by often driving me around to locations, and providing moral support and encouragement, but also by pointing out good camera positions. I owe a lot to Tina, whose photos can be found at http://snupsphotos.blogspot.com.
Composition, Part 2 - Composition and Subject in Landscape Photography
A WHILE BACK, I got a somewhat difficult assignment: I was to photograph a considerable number of city parks for a coffee table photo book. While I liked my architectural photos, I’d always been rather disappointed with my landscapes, as I mentioned in an earlier article, Composition, Part 1 - the Frame. My publisher, Reedy Press, must have thought I was up to the task, even though I was uncertain. But with a year to study, experiment, and shoot, I was able to successfully produce many good photos. Certainly I’m no master of the subject, but I think it might be useful to share some of what I learned while shooting this book.
The final book, St. Louis Parks, turned out well, and it is well-recieved by the public. Please click here if you would like to purchase a copy, autographed by me.
My publisher selected the photo above for the cover of the book, and I generally like it. It isn’t perfect — the sky appears to have a slight greenish tone, especially when seen under fluorescent illumination (although it is correctly white-balanced, and I didn’t alter the hue in post-processing), and the image is a bit darker than I’d like. The formal symmetry, with the fountain and building centered with each other and with the frame, is pleasing to me, but it is slightly off — although this is offset by the presence of the spine, not seen here, on the left hand of the book. What makes the photo, I think, is the presence of teenagers enjoying the fountain; having human subjects in a landscape photo is often appealing. The photo is technically OK, has a good subject, and is composed adequately, making it, in the opinion of my publisher, good enough to be on the cover of a book.
Generally speaking, there is a certain lightness of spirit or relief you can get when you leave certain decisions to others — were I to have selected the photos for the book, I think I would have agonized too much over them, seeing little else than flaws. Instead, my publisher selected images that he thought had general appeal, and he usually selected my favorites. Artists are often not the best judges of their works. Getting a sense of what is good takes understanding, time, and experience, as well as receiving the good judgement of others.
The first step towards getting better in photography, or any art, I think, is to understand why your works are disappointing, and understanding what makes good images superior. This can be exceptionally difficult, for oftentimes it is hard to put vague feelings into words. Determining what actions to take can be difficult also, for it requires an understanding of the technology. For example, you may find that your photographs are too yellow, but you have to understand color theory in order to know that you must make the photos more blue to cancel out the yellow, and you have to understand manual white balance on the camera, or the use of post-processing on the computer to correct for this flaw.
The final book, St. Louis Parks, turned out well, and it is well-recieved by the public. Please click here if you would like to purchase a copy, autographed by me.
My publisher selected the photo above for the cover of the book, and I generally like it. It isn’t perfect — the sky appears to have a slight greenish tone, especially when seen under fluorescent illumination (although it is correctly white-balanced, and I didn’t alter the hue in post-processing), and the image is a bit darker than I’d like. The formal symmetry, with the fountain and building centered with each other and with the frame, is pleasing to me, but it is slightly off — although this is offset by the presence of the spine, not seen here, on the left hand of the book. What makes the photo, I think, is the presence of teenagers enjoying the fountain; having human subjects in a landscape photo is often appealing. The photo is technically OK, has a good subject, and is composed adequately, making it, in the opinion of my publisher, good enough to be on the cover of a book.
Generally speaking, there is a certain lightness of spirit or relief you can get when you leave certain decisions to others — were I to have selected the photos for the book, I think I would have agonized too much over them, seeing little else than flaws. Instead, my publisher selected images that he thought had general appeal, and he usually selected my favorites. Artists are often not the best judges of their works. Getting a sense of what is good takes understanding, time, and experience, as well as receiving the good judgement of others.
The first step towards getting better in photography, or any art, I think, is to understand why your works are disappointing, and understanding what makes good images superior. This can be exceptionally difficult, for oftentimes it is hard to put vague feelings into words. Determining what actions to take can be difficult also, for it requires an understanding of the technology. For example, you may find that your photographs are too yellow, but you have to understand color theory in order to know that you must make the photos more blue to cancel out the yellow, and you have to understand manual white balance on the camera, or the use of post-processing on the computer to correct for this flaw.
Saturday, May 12, 2012
Digital Forensics
HAS A PHOTO been severely altered? I’m sure you’ve seen examples of photo forgery lately in the news media. How exactly can you detect if a photograph is a composite of more than one original camera image? How can you tell if the clone tool has been used on an image, replacing scene detail at one part from another?
See the Digital Forensics webpage for original research by Hany Farid and his group at Dartmouth College.
Of particular interest is a large PDF file of lecture notes, which starts out with a number of famed doctored photographs from history, and then immediately jumps into complex mathematical examinations of digital images.
See the Digital Forensics webpage for original research by Hany Farid and his group at Dartmouth College.
Of particular interest is a large PDF file of lecture notes, which starts out with a number of famed doctored photographs from history, and then immediately jumps into complex mathematical examinations of digital images.
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