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A Book on General Image Editing Concepts?
halftrack asks: "Someone I know wanted 'Photoshop for Dummies' for Christmas because she wanted to learn how to use it properly (who hasn't struggled trying to draw a simple line?) However, having a strong disliking for any sort of vendor lock-in I went searching for a book that would teach image editing without tying it too strongly to Photoshop (or Gimp for that matter). However, all my searches turned out blank. Thus I was wondering if there exists such a book, or is the field too diverse? The ideal would be a (thick) book that would cover the basic concepts (layers, paths, selections, channels etc.,) before presenting how these concepts are implemented in different applications. Such a book should provide the reader with a portable skill-set and give her/him the ability to objectively choose the right tool for the job, at the right cost. Does this book exist?"
...so it would probably be just silly to teach it without teaching to a specific program. If you're going to learn by doing, you have to do it as you go along, and to do that, it has to be taught to the program. You can't teach digital image editing in the abstract any more than you can teach painting without ever picking up a brush. Start off with a book for whatever program you feel comfortable with, and then go from there. It shouldn't be too hard to transtition from one to the other, but it's better to have a solid basis in one program than some abstract ideas with nothing to tie it to.
Remember, there were no nuclear weapons before women were allowed to vote.
You have a friend who wants to learn Photoshop, so instead of finding a good Photoshop book, you're on a quest to find something to find a book that teaches graphics editing without actually teaching it.
Forget the "lock-in" nonsense. Every editing program rips Photoshop, as it is the gold standard for such programs.
Conformity is the jailer of freedom and enemy of growth. -JFK
If she is thinking about persuing a professional career in graphical editing, Photoshop is it.
The only reason I could think of to look at the other apps/books is if and only if this is for personal use only.
1;
It's not diverse at all; if you're going to do image editing/manipulation, there are only really four or five programs out there 'worth their salt', depending of course on what your primary motivations are.
Photoshop, Illustrator, Xara, Paintshop Pro, and a few others.
Notice GIMP isn't listed; not because it isn't any good, but because it hasn't been vetted, or 'peer reviewed' by an industry for several generations.
If your friend wants to use Photoshop, then get a book pertinent to Photoshop.
If later Xara or Illustrator or something else is more pertient, then get that book; the generalities learned in Photoshop will still be relevant, but the specifics will need detailing. It is like you trying to learn Java or Python or Ruby, and a friend saying, "Well, I don't want to get them a language specific tome, so I'll just get them a data structures book and a book on object oriented design and let them figure out the language by themselves."
You can learn about data structures and OOD/OOP using any language, and if you learn those concepts properly you can transplant them into any other language, so don't worry about your friend learning in Photoshop.
GPL Deconstructed
First of all, I think it is more lack of diversity that is causing it being hard to find generic books on the subject.
Next, while I'd prefer a book like you describe, for many people that is something that they are not even going to start on, they want something practical that allows them to get somewhat direct result. Many people I know who use either Photoshop or the Gimp while not being a graphics professional do so with some very specific purposes in mind (ie, my girlfriend uses it for manipulating and somewhat enhancing pictures of things she makes. While showing the concept behind layers was a kind of revelation to her, and is something she uses when it makes sense now, most things she does is simply following a 'guide' for getting a specific kind of effect or enhancement.
What did help her a lot more with getting a better result in the end was a semi professional camera and some practical photography experience and explanation, including some general theory of picture composition and lighting. Worked better because well, a better source is a great help in getting a better result (tho you can still mess it up badly later of course), is something of which cause and effect are relatively easy to demonstrate without needing too deep an understanding of the underlying theory, and of course it simply reduces the need to use things like photoshop beyond making a proper cut or maybe some sharpening or softening.
At any rate, I'd investigate what the intended use of the book is for your friend, your idea may be very good, but could as well end up on a bookshelf without ever serving its real purpose.
There are tons of filters for image processing, but I'll be damned if I know what they all mean. Instead of telling us which buttons to push in Photoshop, maybe they could stop and tell us the concepts behind them. What exactly is a convolution matrix? What is an unsharp mask? What's a gaussian blur? What is laplace edge detection? Etc, etc.
Filters are but one example. I would also like to know how to lighten an underexposed picture without making it look washed out. And other things like that.
A Government Is a Body of People, Usually Notably Ungoverned
Since day one of the consumer era of computing, the industry has insisted on teaching us which buttons to push instead of what the concepts behind them mean. For the most part this makes sense, because the average consumer could care less about the "why", wanting to know only the immediate "how". But not everyone is this way. Surely there's a small market out there for the "why" of computing.
Remember back to the 80's. Remember when people used to take classes in WordPerfect, or Lotus 1-2-3? Hell, I know one guy who actually got an A.S. degree in DOS! Ten years later that knowledge is worthless. Ten years from now these current classes in MSOffice will be worthless as well. Tears still come to my eyes whenever I see a 1980's office secretary passed out in the gutter and clutching a decrepit WP5.1 keyboard overlay...
A Government Is a Body of People, Usually Notably Ungoverned
But you can. There are basic artistic concepts (Golden mean, rule of thirds, composition, balance, color theory, etc.) that apply just as well to charcoal, pencil, crayons, and finger paints. For that matter, they apply to photography. More specifically, there are basic techniques that apply no matter what image editor you are using.
What you can't do is a step-by-step guide covering every different way to achieve the same thing with different tools. You couldn't even cover all the different ways to do it with the same tool.
A book like the submitter suggested would be a valuable resource for learning what tools are available and why you would use them. Then you could refer to the manual to figure out how to do it with your particular tool. Being a Gimp user, that's basically what I do anyway.
When will Windows be ready for the desktop?
Not because of vendor lock-in - I really don't care about that and I do own a copy of Photoshop. But because it would be nice to understand the concepts. For instance, I'm told to blur something in step by step directions, but not told why blurring is a good idea and what kind of effects it performs.
Something that described how to draw or how to paint, but with emphasis on how to do it electronically instead of by hand.
I really think I'd have an easier time with something that was a blend of conceptual ideas (which are rare in these books) and concrete examples (that are everywhere, of course).
So if anyone can suggest such a book, I'd love to hear ideas.
D
This whole thread is a sad comment on the state of computing as a field of study. People confuse "Alt-key trivia" with understanding computers.
As a longtime photography enthusiast, I understand the concepts of gamma curves and color temperature. I know that I want detail in the shadows and in the highlights. Since I have deep knowledge of photography, it doesn't matter which program I use. I can produce "better" results in 5 minutes on any image editor than than someone who has read a photoshop book, but doesn't understand the concepts involved could in an hour.
I think the whole "windows vs. linux" problem is the same. I can switch freely between Mac, Windows and Linux without any loss of productivity because I understand conceptually what I'm doing.
find a host, start a wiki and lets write the book. (When its done, we publish and split the profits among those involved ;-), no, not really)
/. who know these programs in and out. I am no GIMP expert, but I spent 12 years in printing doing photo retouching with Photoshop. I think I know it pretty well...Just from having done so much of this, I know the theory behind a lot of it. I would contribute to such a site. I get tired of having people ask me how to do something, or how something can be done, and of course they do not have Photoshop. They may have GIMP, but I can tell you the keystrokes in Photoshop, not GIMP. If I could point them to a place where they can learn the theory, with notes on the implementation by the different programs, it would be great. If you really are interested in this, then do more than just ask slashdot, set upa project and lets get started.
I know there have to be some folks here on
I reject your reality
The book that you are looking for is called Real World Photoshop. It's not going to teach you how to apply lens flares and things like that. What it does go over is how to get good scans, how to properly apply colour correction, how to adjust the exposure without making it looked washed out, etc. It also explains the hows and whys of the things you were asking about such as blurs and sharpening.
Slashdot: Failed Car Analogies. Amateur Lawyering. Anecdote Battles.
I wonder if knowing those things help?
Convolution Matrix: reads a 3x3 or 5x5 area of pixels, 'multiplies' that grid by the convolution matrix, performs a sum of the values, and replaces the central pixel in that 3x3 or 5x5 grid with the cumulative value.
Does not explain at all HOW this produces sharp filters, but that's a convolution matrix.
Unsharp mask: Creates a blurred representation of the image, compares it to the original, and any place that is similar in value remains unchanged. Any place that shows a difference indicates a boundary, and that area is brightened. The point is that you fool the human eye into thinking an image is 'sharper' because the edges are more in focus. This is akin to drawing black lines on a cartoon to make the edge more distinctive.
This doesn't explain of course why radius, amount, and threshold are used.
Gaussian blur: Uses the guassian function to average pixel values (like in the convolution matrix!). The gaussian function is the probability function of the normal distribution.
This doesn't explain how it works either.
What is probably most useful:
Convolution matrix: Create a grid of weights that is multiplied against a grid of pixels; the sum of these products is then used to replace the center of the grid, normally 3x3 or 5x5.
Unsharp mask: Increases the contrast around the edges in a picture; threshold limits how blurry an edge can be, radius tells the function how far away to look for an edge, and amount tells the function how much to increase the contrast.
Gaussian blur: Averages the values around a pixel using the Gaussian distribution, otherwise known as a bell curve. The Guassian function is used to populate the grid of a convolution matrix.
GPL Deconstructed
If you aspire to be a hardcore Photoshop user, this book is probably the one you want above all others. It's not a step-by-step tutorial, a mere reference book, or a book that leads you through the tools and various functions of the software. Instead it discusses the fundamental concepts you need to know to use Photoshop to its fullest. ... Most of the book is still applicable since Photoshop today still has channels, alpha channels, paths, layers, and calculations. This book hasn't been updated since it was written in 1998, but it really doesn't need to be. It's not about how to use particular tools and new features. It's about how to think with Photoshop. ...
Unfortunatelly it is out of print:-(