Ed Schlotzhauer

An artists journey

Category: Mastery

  • Pixels, PPI, DPI

    Pixels, PPI, DPI

    Pardon me, but sometimes the Engineer in me has to rant. I see so much confusion about pixels and how to scale them to an output size. Pixels are just an RGB dot. How they are presented is up to the output driver. It is complicated at a technical level, but it does not have to be complicated to us poor users. So let’s see what pixels and PPI (pixels per inch) and DPI (dots per inch) really mean mean.

    What are pixels?

    A digital file is just a rectangular array of pixels. The term “pixel” is a contraction of “picture element”. It is the smallest dot the sensor can resolve or the smallest point of light a display can produce.

    Getting to the array of pixels is complicated, since camera sensors don’t read them directly. See my article “How We Get Color Images“. Regardless of what magic actually happens, by the time you view an image on your computer monitor, it is an array of pixels. Conceptually each pixel is represented as a triplet of (Red value, Green value, Blue value). Each of the values is a number from 8 to 16 bits in size. So each value has a magnitude of 0 to 255 or 0 to 65536. What sizes you actually have is determined by the capability of your sensor (the dynamic range) and camera and the color space you are using.

    Pixels have no physical meaning. In the main camera I use, the array is 8256 x 5504 pixels. Again, it is just a number. It has no physical meaning. It has no relation by itself to a print size or the size of the image on screen.

    What PPI should I use for display?

    This is the thing that annoys me the most. I constantly see museum and gallery directors put out requirement that we have to send in electronic samples sized to 72 PPI. PPI stands for pixels per inch.

    Way back in the dim distant past, computers only did text. Then Apple came along and wanted to do graphics. They did research and decided 72 PPI looked good on screen. This set the standard, but hasn’t been the case for eons of computer age. The display on my fairly old iMac is about 218 PPI, physically. But the magic 72 PPI stuck with a lot of people.

    The increases in PPI density and bit depth and speed of monitors is one of the great technological advances of computers in recent years. All those pixels on screen makes for very sharp and smooth images. We can see so much more.

    Worse, many people have been led to believe that the PPI sizing of the image files means something. It doesn’t anymore. Actually, it never did for images displayed on screen. The PPI setting has little or no meaning for an image displayed on screen.

    Try it

    Try an experiment: take an arbitrary, fairly large jpg file of your choosing. Let’s say the filename is MyFile.jpg. Load it into Photoshop and resize, WITHOUT RESCALING, to 72 PPI. Save it as MyFile-72.jpg. Now reload the original file.jpg and size it to 360 PPI. Again without rescaling. Save it as MyFile-360.jpg. Rescaling changes the number of pixels in the file. We just want to change the PPI setting. These 2 files now have the same number of pixels but different ppi scaling.

    Now use whatever image preview application you like and view the 2 sized files. Is one of them 5 times larger than the other? On my system, they are exactly the same size on screen. Even though one is set to be 72 PPI and one is 360 PPI. They are displayed as the same size and the same resolution.

    Why is this? Because the file PPI setting means nothing. The display app just looks at the number of pixels and decides how large it is going to make it. If it is a tiny image, say 300×200 pixels, it will probably make it very small to avoid pixelization artifacts when an image is enlarged too much. It it is a reasonable sized file, it will just pick a good output size. It makes these choices based on the number of pixels. If the image is in a web page, the web page code determines the size the image will be.

    What PPI should I use for print?

    Now we head into an even more confusing area, and here the confusion is somewhat justified. Printing is it’s own special world. The technology and perception is very different from displays. Displays emit light. Prints reflect light. The effect to the viewer is very different.

    Printers don’t have pixels. Instead, we refer to the output scaling as DPI – dots per inch. This recognizes that we are now talking about physical marks on paper (or your substrate of choice).

    The printer manufacturers have created tremendous confusion in customer’s minds because they overload terms. The Canon Pro-1000 printer I have at my studio has a specified print resolution of 2400 DPI horizontally and 1200 DPI vertically. Yet the optimum print resolution is 300 DPI. That is, when I am creating a print, I should try to set the output resolution to 300 DPI. This is bound to confuse most people. Why not set the output to 2400 dpi for maximum resolution?

    How inkjet printers make nice prints

    We come to one of the secrets of printers. We customers want prints with crisp lines and smooth gradations of color and tone. As natural as film used to be, or as smooth as the original artwork we are copying. An inkjet printer sprays dots of ink onto the paper. A dot or no dot. At the level of a single dot, this is not smooth. Inkjet inks do not “mix” to create new colors.

    So take my Canon printer as an example. Each “dot” (at 300 per inch) is actually subdivided into an 8×4 grid – 8*300 is 2400 dots per inch horizontally. Any position in this 8×4 sub-grid can contain any combination of printer dots of any of the 12 colors. The print driver uses a magical algorithm called “error diffusion” to cover the sub-grid with a blend of printer dots of the available colors that simulate the color and intensity of the pixel to be printed there.

    It is mind bending in it’s complexity. One reason they don’t talk about it much is that it is proprietary for each manufacturer and printer, a closely kept trade secret. The good news is that they take over this complexity so we don’t have to. And they do a very good job. So I set my image to print at 300 DPI and magic happens.

    It usually doesn’t matter

    In summary, PPI settings do not matter for images displayed on your monitor or on the web or sent to your social media account. If someone tells you they need their images scaled to 72 PPI, just smile and do it, but secretly know they do not know what they are talking about. Only the total number of pixels affects the size of the image. And without going into mind numbing detail, I hope this takes a little mystery out of the way printing works.

    I feel better now. 🙂 How about you? Are you more or less confused?

  • Photoshopped

    Photoshopped

    It may be said as an insult. It may be used to shame the photographer as “not a purist”. But should it be? What is wrong with an image being Photoshopped?

    History

    Photography began as a medium of realism. It is said that Impressionist painting (Monet, vanGogh, etc) was a reaction to the realism of photography. They took their art is a direction photography could not challenge – at the time.

    Have you ever thought of traditional painting changing its direction because of photography?

    The development of Impressionism can be considered partly as a reaction by artists to the challenge presented by photography, which seemed to devalue the artist’s skill in reproducing reality. Both portrait and landscape paintings were deemed somewhat deficient and lacking in truth as photography “produced lifelike images much more efficiently and reliably”.[31]

    Because of the history, and the fact that everything the lens sees is recorded in detail, people tend to have an expectation that a photograph is “real”. A picture can’t lie.

    Not only is this wrong in so many ways, but it is no longer a realistic expectation of photography.

    Common practice

    All photographs are altered from what the sensor recorded. Even if you just take that picture you snapped on your phone and post it to social media, it was altered a lot before you ever saw it. All sorts of distortion corrections, color enhancements, gamma correction and noise reduction was done by the phone. Their algorithms are very good at making the picture look like what you expected to see. It is not the same as the phone recorded.

    All images you see in prints or any media are altered – Photoshopped. Some massively. Some just minor color correction and tone enhancements. I would never insult you by showing you an unprocessed picture. Unless it was to make a point about the kind of processing I do.

    Even to do black & white these days requires a lot of image processing.

    Did you know that even movies are “Photoshopped”? An obvious example is CGI. That stands for computer generated imagery. It proudly states that a lot of what you are seeing is artificially created. And we love it in big action movies.

    Nearly all movies are digitally recorded now . All are processed and retouched frame by frame in addition to CGI enhancements. The overall color you see is even completely controlled. They call it color grading. The entire look and shading of each scene is digitally processed to set the mood the director wants.

    Bad Photoshopping

    One thing I will join people in denouncing is bad Photoshopping. Photoshop is a very complex program to master. It can take years – and they are constantly changing it. But even so, we are artists. We have no excuse for not mastering our tools.

    Not knowing how to use the tools to accomplish our vision is like a painter not knowing how to use a brush or a metal sculptor not knowing how to weld. Just using some simple sliders to make the color of an image wonky is not much of an artistic statement.

    Yet I have heard well-known professionals almost brag about their limited knowledge of Photoshop. But the reality is that they know enough to do what they want. The exception is Jay Maisel. Jay is one of the greats who I admire. He brags that he does not even have Photoshop on his computer. That is probably true, but he has full time assistants who do have it and can make a picture look like what he tells them he wants. So, a slight exaggeration for dramatic effect.

    For the others, though, who really do not know Photoshop well: spend time learning it. It will reward you by making you more efficient and it will open up new artistic possibilities for you.

    Artistic expression

    My work is called “fine art”. I don’t like the term, but we are stuck with it. Fine art, among other things, means it is not literal or representational. I feel free to bend and even break pixels to any degree I want to bring you the art I see.

    I guarantee that any image of mine you see has been processed in Lightroom Classic and maybe Photoshop. Both great tools are well capable of altering the reality of the original frame. And I do alter them.

    It can range from basic color and tone correction to removing distracting elements to compositing several images together to create something new. Anything is fair game. The more adapt at my tools I get, the more I am able to use them to help me change my vision. It is circular: what we find out we can do helps us to see new things to do.

    Accept it

    I accepted it a long time ago. My Photoshopping goes back to about version 5 or 6. In the beginning, I was mostly just doing minor corrections on my very realistic landscapes. I have fond memories of the controversy in the camera club I was in at the time when I won best of show with the first digitally manipulated image ever submitted to them.

    Since then I keep widening my vision and perspective. Realism was so deeply ingrained in me that I have had to work at giving myself permission to let my imagination go free.

    I’m not where I want to be yet, but I take a much more liberal view of what I can do in an image. Still, I am my own limitation.

    If you are seeking “truth” in images, be careful. But if it is important to you, do some research to find out if the image has been manipulated materially. It has been manipulated. but that doesn’t mean content has been added or deleted.

    Finding truth is rare in our world. When you look at an image, assume it is art, not truth. At least, that will be true for my work. I may bring truth, but that does not mean it is realism. My images are photoshopped.

    The future

    In the 19th century, painting was mostly about realism. Then photography came along and took over realism. So painting moved to Impressionism and modernism and abstraction. Now digital art is perfectly capable of creating any abstract or impressionist images we desire. Where will painting go next to separate themselves?

  • Reality is Overrated

    Reality is Overrated

    Is this controversial for a photographer to say? I hope so. 🙂 Photography used to be the land of total realism. Not so any more. Photography for me is purely artistic expression, with little concern for reality. That’s because reality is overrated.

    Reality – the good

    There is a long and honored tradition of highly realistic landscape and street photography. When you think of landscapes, you might think of John Fielder or Art Wolf or Ansel Adams. For street photography maybe it is Henri Cartier-Bresson or Jay Maisel or Elliott Erwitt.

    All of these artists were true to the reality of the scenes they found. Of course they looked for the best composition or the right light or the dramatic expression – that is why they are recognized artists. But the photographs they took were not modified at all, other than routine spotting or color corrections.

    Is their work good because they only shot reality? No, their work is good because they are great artists. I could walk outside and shoot a picture looking down my suburban street and publish it. It would be absolutely real and unmodified. Would it be good art because of that? Not to me.

    Reality – the bad

    Following up on the point about shooting down the street, a picture isn’t good just because it is reality. Reality can be boring. It can be depressing. It can be dreary and banal. While there may be a time and place for these things, they are not where I want to spend much time.

    I am not a critic or authority. I would never say such subjects do not constitute art. But don’t get caught up in the post-modernism depression where you don’t view art as worthwhile unless it is depressing or banal. That is just one passing movement led by some people with a very dark world view.

    Be yourself. Express your own values. Like, and buy, what you like.

    Assume no reality

    Photography has become much wider and more diverse than it was a few decades ago. It used to indeed be true that “a photograph didn’t lie”. You could believe what you saw. Not anymore. Photojournalism may be an exception, but in today’s climate, I wouldn’t rush to ascribe too much credence to any particular image you see on the news unless you know the circumstances. News has become just a business, not a guardian of truth.

    A lot of artists, including myself, no longer consider it necessary to represent reality. Now, some of my work is extremely detailed, with sharp, crunchy texture and edges. I actually like doing these sometimes. It is almost reveling in the detail that can be captured by my sensor and lenses. Quite the opposite of some of my blurred, low texture images.

    But if you see one of my images with super sharp detail, don’t necessarily assume it is reality. Even when I am going for crisp and detailed, I am not at the same time representing to you that it is reality. It could be manufactured. Even if I know that it is real, it could look so abstract to you that you could not describe exactly what it is.

    It is art, not a documentary

    My point being that I am making art. I think most “artists” are making art. Enjoy it as art. Don’t be disappointed if you find out it is not reality. I’m not sure there is much overlap between art and reality.

    Art may speak to universal truths and bring deep insights into our lives, but it does it through its metaphors and imagery. It does it by touching something within us. In the same way that Shakespear gives us a lot of insights about life, even though his stories are fiction.

    So don’t assume photography has to depict reality while painting does not. Both are art.

    It is art, not reality

    I will go out on a limb and state that art is not reality and it cannot be. Art might show a representation of reality. Even a very realistic representation. But the art is not the reality. Art is a 2 or 3 dimensional object you look at.

    To take an example that may be easier to comprehend, it is like a book. An excellent work of fiction may create a reality in our mind, but that reality is what we interpret from what the book describes. The places may seem real. The characters may seem real and alive to us. But they are feelings the author has communicated to us through the words. Not reality itself.

    I am drawn to joy

    On a personal note, I am drawn to joy and things that are uplifting. Even when my images are dark or showing bleak mid winter scenes, they are not depressing. At least, not to me. I try to find a hopeful angle on my art.

    For instance, I love finding certain types of old rusty trucks and cars. After surviving for 50 to 90 years, it seems these relics have something to tell me. They have resisted the elements far longer than most things. They may be beat up and rusty and out of service, but they are still there defiantly. That is the joy to me in old things like this. They are still standing and making a statement; they are not junk. There seems to be something significant about that generation. Some quality that makes people want to keep them. A 1952 truck is often still around in 60 years. I don’t expect that many 2022 trucks will still be in as good a shape after 60 years.

    The picture with this article is composited from shots of some old vehicles. It is detailed and sharp, but it is not “real”. No object I know of in the world actually looks exactly like this. That doesn’t keep me from creating it. I could even represent it as something that could be, even if it does not currently exist. But realism or potential realism is not an important consideration for me. I only care about if I like it. I do.

    What do you think?

  • Raw Material

    Raw Material

    I have come to consider many of the images I shoot to be raw material. They don’t become a finished picture until I have worked the raw material in post processing.

    Bits

    Today’s cameras are great generators of data. Every time I press the shutter I am sending around 50-60 MBytes of data to my memory card. And that is using a compressed RAW format.

    A funny thing happens, though. The more data there is, the less the importance of each bit. For instance, even though my camera has great metering and a live histogram, I may shoot several frames of the same subject. This will allow for minimizing motion or camera shake. Or, if I am intentionally moving the camera (intentional camera motion) I will shoot many frames to up my chance of getting a keeper.

    I never would have been so “wasteful” with film. It was too expensive. But digital images seem free. The perceived value of any frame is smaller.

    But a side effect of this commodity view leads to a different relationship with the image data. It is no longer necessarily a “picture” as an indivisible unit. It is data. I feel more free to repurpose any of the picture data for other uses.

    Repurposing

    So now I have new ways to look at an image. Maybe I like its texture and want to apply it to another image. Maybe there are one or more elements in the picture that I think would be good included in another image. There could be a form structure that could be used to build another image.

    I have moved from a “take it or leave it” judgement of an image as a whole to a sense of “parting out” a picture to harvest the good parts. That is so much easier now than it ever was in the past. The tools are there, it is a matter of adjusting the mindset.

    Post processing

    In today’s world, post processing is where a lot of the magic happens. Photoshop and Lightroom and some of the other editing programs have developed marvelous feature sets. They can handle large files and 16 bit depth and work comfortably in good image spaces like ProPhotoRGB, Photoshop is the choice (IMHO) for heavy duty pixel pushing.

    It is almost (not quite) true that is you can think it, you can do it. The tools are not perfect, but they are so good that, for the most part, they stay out of the way and let us create fluently with them.

    A lot of us have come to believe that a picture does not become a picture until we have spent some serious time in post processing. There is no reason anymore to be limited to what we originally captured, unless it turned out to be exactly what we want.

    Vision

    We artists are no longer “stuck” with what we captured at the moment we pressed the shutter. We have huge latitude for changing the look, the content, the color, and the whole feeling of the image.

    Some people are threatened by this, but I see it as an opportunity to realize my vision. There are few excuses any more. Photography is very different from painting, but we have one new similarity: if we can think it we can create it.

    Emotion

    To bring you a good image, I have to show not only what I saw but how I felt about it. Revealing the emotion behind it is easier now. Because we do not have to take the original bits of the image as fixed and unchangeable, we can add or subtract as necessary to achieve the effect we desire.

    This can be a very freeing and empowering realization. Those of us who have done photography for a long time have to re-learn how to approach image making. We have to give ourselves permission to do any amount of modification, even to the point of completely creating a new work out of raw material from others. But it gives us a medium for expressing ourselves more fully.

    This image

    The image with this article is an example. That is not what the original scene looked like. No in-camera technique could have given the resulting image. A lot of Photoshop time was spent in blurring the image except for the evergreens. It is not what I saw when I was there. I did not even envision this at the time. I spent time thinking about surreal variations and eventually visualized this.

    Dishonest?

    This is not dishonest. It is the same thing as a painter painting in what he likes and leaving out what he doesn’t like. The end result is art, not documentation.

    Art is neither honest or dishonest. It is art. It means what the viewer takes it to mean. We are long past the time when we assume a photograph is “truth”. We should assume that every image is altered, composited, tweaked, and blended. That’s not just OK, it is healthy.

  • Evolution of an Image

    Evolution of an Image

    Not all images follow the same life cycle. Sometimes it is pretty straightforward. See a scene; click; some post processing; done. Other times the path is winding, even circular. It is impossible for an image to be ready for a final print right out of the camera. Sometimes that shows an evolution of the artists perception of an image.

    Of something

    A lot of very good pictures are simply images of something. We find a lovely or interesting scene and we take a picture. Yes, we work the scene, find a good position to make a good composition. Wait for great light. Then make the shot.

    It represents something real and concrete. It is what it is. There is nothing abstract or surreal about it. No hidden meaning. As I write this I am on a trip going through a part of the country that has lots of beautiful trees. I am shooting a lot of pictures of trees. Just because I like them. And they’re all around.

    Most of these images, though, are ending up being just pictures of trees or fields. That doesn’t mean I don’t like them, but they are straight forward record shots of a scene I saw. It is the rare one that seems to actually have something deeper to offer.

    About something

    A goal is to bring something more than just a “here is what I saw”. I hope to occasionally make a statement or observation that will be helpful or insightful. Hopefully, I can bring you something more than just a pretty picture. I can only reveal to you what I emotionally reacted to at the time. It is up to me to react to the scene and be able to bring some of that to you.

    This is a wide grey area. One person’s “depth” may be another person’s “duh”. My perception of the significance of something may be different from yours. All I can do is to say what I think. I cannot control how you receive it.

    And the degree of depth or insight will vary all over the place. An image may have insight on something of human nature, or it may be humorous, or it may be ironic, or it may make a statement about the march of time or environmental issues. Good images do not have to be deeply serious. Few of mine are heavy commentary on social issues. My reaction to the world is governed more by joy and gratitude.

    So when you see my images, assume they probably have some insight I have perceived about the scene or subject. It may not be dark and depressing, but that does not take away from my intent to say something.

    A life of its own

    Sometimes, though, an image takes on another direction, a new life. I occasionally recognize that the original image is not complete or fully formed. It may need to be combined with other images or heavily worked to change it into something different.

    Take the image with this article for example. It started out a fairly interesting shot out of a favorite restaurant window. This particular window had 100+ year old glass that was wavy and distorted. Blurred in the background were some downtown buildings, trees, awnings, etc. I liked the scene and shot it repeatedly until I captured the impression I wanted (many lunches there!).

    But I was not happy with it as it was. It was an abstract view of downtown, but it was too abstract to be an effective representation of a downtown street, but not abstract enough to become something completely different and interesting in it’s own right. So I decided to go much further.

    Ah, the joys of Photoshop. It is fun to play sometimes. I added textures and played with colors and saturation and hues. Some overlay patterns gave it more definition and shape. Pretty soon it had nothing to do with the downtown scene I originally liked. If you sat where I shot the picture and looked out the same window, you would not recognize it.

    The image now has a life of its own, completely independent of the original scene. I like it. It is a fun creative exercise. But I have to find the right base images to work with. And I have to form a vision of where I want to go. Only a few images are good subjects for such a treatment.

    It means what it means

    Coming to this point requires me to address the question of what does an image “mean”? Can a picture have a meaning? Does it have to?

    There seems to be at least 2 opposing groups. Some say a picture is worthless unless it means something. The other says very few pictures can have an actual meaning, except for some photojournalism. As in most things in life, I range somewhere in the middle. Generally I say don’t take yourself so serious. A good picture can just be a nice, pleasing picture. If I have the opportunity to make images with meaning I usually will, but I don’t want the meaning to get in the way of the quality of the image.

    I get frustrated with people who are so sincere and focused on something that is important to them that they feel everyone must share their angst. Lighten up. First make art.

    I do make images with meaning, especially if I am shooting a project that is fairly serious. When I have the filter of a project in mind my focus tends to narrow to the subject. But unless it is a particularly dark and depressing subject, I want to concentrate first on making art. I tend to avoid the really dark and depressing projects. That is just not me and I don’t think they would make your life better.

    Summary

    The vast majority of the billions of photographs shot each year are record shots of something. They serve to capture a memory or mark an occasion. This was their intent and the work for that.

    A small percentage of photos and paintings go further and reveal something interesting. Maybe it is a new insight on a subject. Maybe it is just the artist’s emotional reaction at the time. But we look at them and often agree that they bring something deeper than just a snapshot.

    Or sometimes a picture becomes a thing in itself. Not a representation or even an interpretation. It just exists as a new creation. A lot of abstract and surreal art is like this.

    In my case, I am a lens-based artist. That means I start from something concrete – an image – rather than a blank canvas. Sometimes as I live with an image and think about what it could be, I morph it into something new. That is the case for the image with this article.

    I’m not saying this is a desired evolutionary path for an artist or that some steps are better than others. But artists tend to evolve their skills and viewpoints as they mature. I have observed myself moving through a progression. More and more of the images I like are abstract.