IntroGimp

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Ubuntu Open Week -Intro to GIMP - akk - Wed, Nov 4, 2009

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(03:02:38 PM) akk: Hi, all! Welcome to the GIMP session!
(03:02:50 PM) akk: I'm Akkana Peck -- I wrote "Beginning GIMP" (gimpbook.com) and I've been involved with GIMP for 8-9 years.
(03:03:12 PM) akk: You all probably know what GIMP is, but it stands for GNU Image Manipulation Program,
(03:03:12 PM) akk: and what it does is edit images.
(03:03:57 PM) akk: If anybody has specific techniques you'd like to learn (or other questions),
(03:03:57 PM) akk: ask on #ubuntu-classroom-chat.
(03:04:21 PM) akk: If you don't have any of your own photos handy for following along during this session,
(03:04:29 PM) akk: you might like some of the ones at http://commons.wikimedia.org/wiki/Koala :)
(03:05:02 PM) akk: And a tip to start out: you may be able to drag from Firefox straight into GIMP
(03:05:09 PM) akk: (drop it over the Toolbox -- the small window with all the buttons)
(03:05:40 PM) akk: Drag-n-drop works in a lot of places in gimp (I'll talk more about that later if I have time).
(03:06:11 PM) akk: For commandline junkies (like me), you can also run gimp foo.jpg bar.jpg ... and it will open in your already-running GIMP -- that's how I most often open images.
(03:06:39 PM) akk: Any questions to start out? Does everybody have gimp running and an image loaded?
(03:07:49 PM) akk: I'll start with some really basic stuff (that still confuses a lot of people): scaling.
(03:08:02 PM) akk: You can't put your 5-megapixel image on the web -- people will hate you.
(03:08:37 PM) akk: Image->Scale Image lets you make the image a more reasonable size.
(03:08:49 PM) akk: It brings up a dialog showing the current size of the image. Bring it up and take a look.
(03:09:48 PM) akk: IGNORE the X and Y resolution fields. They don't do what you probably expect.
(03:10:03 PM) akk: Also, that menu over on the right that says pixels?
(03:10:22 PM) akk: It has two useful settings: Pixels and Percent.
(03:10:33 PM) akk: The other settings are misleading.
(03:10:50 PM) akk: You might think 'I want to print out an 8" x 10" photo, so I should Scale to that size!"
(03:11:08 PM) akk: But all GIMP knows about in an image are pixels.
(03:11:14 PM) akk:  If you don't have enough pixels, it won't look good printed.
(03:11:20 PM) akk: If you have too many, it'll be too big to put on a web site.
(03:11:41 PM) akk: (Personally I try to keep web images around 550-800 pixels, biggest dimension.)
(03:11:58 PM) akk: <mhall119|work> QUESTION: what's the best scaling interpolation?
(03:12:22 PM) akk: That's something people argue about. Either Cubic or Lanczos is good
(03:12:37 PM) akk: but Lanczos has some problems in certain situations -- Cubic works pretty well everywhere.
(03:13:12 PM) akk: I usually type my number (600 or whatever) into the Width field then hit Tab
(03:13:12 PM) akk: and the other field adjusts automatically. Then click Scale.
(03:13:29 PM) czajkowski: 20:13 < SoftwareExplorer> QUESTION: Where does Lanczos not do well?
(03:13:31 PM) akk: If you want to scale in only one dimension (not have the other field auto-adjust)
(03:13:47 PM) akk: you can click the little chain-link linking the two fields.
(03:14:18 PM) akk: I actually don't remember the details of where Lanczos breaks down. :) Would have to look it up. Ask me again after the class and I'll find it.
(03:14:41 PM) czajkowski: 20:13 < Jesi> Question: I love GIMP, and actually think it's much better than photoshop, but GIMP is so underrated and many people say they don't like it, but often I find these  people don't give it a chance...they either feel intimidated by it, or simply don't like it because it's not Photoshop and often they don't want to take the time to
(03:14:46 PM) czajkowski:  learn a new prgram (that's understandable), how would yuou go about encouraging someone
(03:14:49 PM) czajkowski: 20:13 < Jesi> to give GIMP a try?
(03:15:38 PM) akk: I agree with Jesi on that. At the same time, I can understand users not wanting to learn a new UI.
(03:16:22 PM) akk: It's possible to substitute a set of key bindings that make GIMP a little more like PS ... but I don't generally recommend that since the rest of the interface is still pretty different.
(03:16:52 PM) akk: Likewise, using something like Gimpshop (a hacked build of gimp) usually doesn't work out very well.
(03:17:14 PM) akk: So I guess I'd just stress to them that learning a new program always takes a bit of time, but can be worth it in the end.
(03:17:43 PM) akk: Okay, I think I'm caught up on questions.
(03:17:50 PM) akk: After you Scale, you get a ridiculously tiny image in a huge window.
(03:17:50 PM) akk: You'll probably want to zoom it to 100%.
(03:18:02 PM) akk: At the bottom of the image window you can see your zoom factor (e.g. 50%, 33%, 100%).
(03:18:16 PM) akk: It's a menu, so you can choose any zoom right there, or from View->Zoom.
(03:18:26 PM) akk: You can also zoom in/out with the +/- keys.
(03:18:45 PM) akk: Or type 1 at any time to zoom to 100% (that's great if you're previewing something you just scaled for the web).
(03:19:00 PM) akk: +, - and 1 are great key bindings -- I use them all the time.
(03:19:16 PM) akk: But after you zoom, the window is probably the wrong size.
(03:19:23 PM) akk: View->Shrink Wrap can fix that, or you can set the two prefs under Image Windows, Zoom & Resize Behavior.
(03:19:42 PM) akk: (I always set those prefs -- it drives me crazy to have a small image in a big window.)
(03:20:16 PM) akk: <itnet7> QUESTION: Is part of the problem in learning from tutorials and such for new gimp users the differences found within options/locations between linux/windows or are the environments relatively the same?
(03:20:49 PM) akk: GIMP is almost identical on different platforms -- the only difference is in window manager behavior
(03:21:19 PM) akk: and platform-specific bugs, e.g. Apple's X11 doesn't support drag-n-drop.
(03:21:35 PM) akk: So tutorials should usually work well across platforms
(03:21:50 PM) akk: though not always across GIMP versions -- the UI has been changing lately and it will change again in 2.8.
(03:22:18 PM) czajkowski: 0:22 < mhall119|work> QUESTION: what interface changes are coming in 2.8?
(03:22:55 PM) akk: The big deal right now in GIMP 2.7 dev is "single window mode", where it will be possible to have everything (including all images) in one big window.
(03:23:27 PM) akk: That's something Windows users ask for a lot, partly because they're used to MDI and partly because Windows doesn't deal as well with lots of little windows as Linux window managers do.
(03:24:03 PM) akk: There are also a lot of drawing improvements, esp. for tablets ("brush dynamics")
(03:24:16 PM) czajkowski: 20:22 < faberglas1> QUESTION Can you reccomend any web tutorials or books for GIMP?
(03:24:33 PM) akk: and things like several tools combining into one, like all the transform tools (rotate/scale/perspective/etc).
(03:25:15 PM) akk: Well, I'm biased but I kind of like my book. :)  gimpbook.com
(03:25:54 PM) czajkowski: 20:24 < the_madman> QUESTION: A lot of my friends in college use Photoshop because they are graphics designers or artists, using tablets. One of the features that makes Photoshop  so appealing to them is the ability to change the brush, e.g. the amount of faded pixels from the edge, pressure etc. While I've seen these features available
(03:25:54 PM) akk: There are TONS of good web tutorials, and even video tutorials like "meet the gimp".
(03:25:59 PM) czajkowski:  in Krita, it fels less mature in comparison to the Gimp. Doess the Gimp support these
(03:26:02 PM) czajkowski: 20:24 < the_madman> configurable brushes in some way I haven't seen?
(03:26:24 PM) akk: I've collected some of the good tutorial collections at: http://gimpbook.com/links.html#gimptuts
(03:27:16 PM) akk: GIMP does support some of those brush operations -- in 2.6 there's a "Brush dynamics" tab in the paint tool options
(03:27:27 PM) akk: and Brush Dynamics is getting a lot smarter and more flexible in 2.8.
(03:27:57 PM) akk: It should be a lot better for artists wanting to draw with tablets.
(03:28:27 PM) akk: But even in 2.6 it can do some of that if you experiment with tool options.
(03:29:26 PM) akk: Okay, I was going to talk about brightness/contrast next, but time is flying by so I'll skip most of that unless people are dying to hear about it.
(03:29:47 PM) akk: I'll just mention that in the Brightness/Contrast dialog there's a feature new in 2.6: "Edit these settings as Levels"
(03:29:53 PM) akk: and from Levels, you can Edit as Curves
(03:30:09 PM) akk: which is a really cool and useful feature, so play with it if you want more control than regular brightness/contrast.
(03:30:53 PM) akk: A couple of questions I missed: <Xiella_> QUESTION: brush dynamics, do you mean rotatable brushes without using a plugin?
(03:31:27 PM) akk: Brush rotation is different from dynamics, but my understanding is that it will be in 2.8. (I hope that's true.)
(03:31:41 PM) akk: <Jesi> Question: You've been using GIMP for several years, and most likely keep up with the roadmap, what can we expect from GIMP in the future (this is an "intro" and I don't expect this question to answered unless time permits :) )
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