GIMP Version: 2.8
Operating System: Windows
OS Version: XP - SP3
GIMP Experience: Beginner Level

List any relevant plug-ins or scripts:
script-fu 101 scripts, GMIC, and layer effects

List any ERROR messages you received:
none

---

Ello all. Just trying to work with the gimp today. Just a reminder, i came from photoshop to gimp so things are out of place for me a we bit. In PS, i could create a new layer, hit the layer style button and throw a gradient over the curent layer. It would bring up an options box that had what they called color stops. little triangles that show where the colors need to stop in a sense. Once it was applied to the layer, you could toggle it on and off. trying to do that with the gimp. i create a new layer, select my gradient colors i want and then i hit the gradient editor button in the tools box. I then see my white triangle in the middle and two half traingles on the far left and right side. however, i can not move them. i click and drag and all sorts of things including shift click and drag. The only change, if i have the mouse pointer in the color preview of the gradient editor, and i do a click and drag, my color changes to match my foreground color.

Im lost to how this editor works. Here is what i am trying to make

http://www.adobetutorialz.com/articles/ ... ree-design

cant find in gimp how to change gradient angle to 150%

thanks

Matt

there is something like Layer Effects for Gimp but it doesnt do what you want to achieve
you can find layerfx here:
http://registry.gimp.org/node/186

what you want to do, is done with the gradient tool and you have to do it manually
so either you stroke the gradient at the angle you want or stroke the gradient and then rotate the layer

a tutorial how you can make a custom gradient is here:


and as far as i know, changing an existing gradient works by right clicking on your gradient and then 'Edit Gradient'

oh dang. thats an intersting way to do things. haha. dang, know i gotta find the stroke option so i can do this. haha. the other issue i am running into is i am supposed to make an elpitcal selection, set opacity to 0%, put another gradient on it and its supposed to make that section brighter than the others without showing the seams of the ellipses. haha. its kind of hard. haha

The 'seams' can be softened by making your selection then go to Select>Feather and set it to 50 or 100 to blend in or sort of blur the edges, then apply your gradient. Alternately you can blur the layer after the gradient has been applied and adjust the layer Mode, Opacity or both.



Have you used the Blend tool before?

man i love forums. i like getting my questions answered. haha. thanks much. i have the weekend toi work on gimp and calc

thanks

matt

i just realized i was talking crap
you can change the angle of your gradient in layerfx but i would still prefer the manual way of doing it

I would recommend not using the Gradient Editor for this. Though it can be done, it would require either a lot of trial and error or a good familiarity with the behavior of the Gradient Editor (if you wish to play around with "adjusting the triangles", you should first "Split the segment"). Also, the examples in that tutorial do not require the full color variations available with gradient editing.

Photoshop's interface is largely based on punching in numbers and checking boxes for options -- this makes things such as Layer Styles easy for Adobe to program, but personally I find it quite unintuitive. GIMP's approach is more organic. Rather than specify angles and scales, you paint the gradient onto a layer using the Blend Tool . The angle is controlled by the direction of your "brush stroke", while the scale is controlled by the length your stroke. When dealing with just FG-to-BG or FG-to-transparency gradients, the "stop points" can effectively be controlled by the start and stop locations of your stroke. However, it may take a little practice until you become proficient at drawing such gradient blends. In the meantime, though, there is a way to otherwise be productive in using gradients.

This approach is to draw a full linear gradient across your drawing and then use either the Levels Tool or the Curves Tool to adjust the "shape" of this gradient. This can be done on a separate layer, thus allowing experimentation with the layer's opacity and blend modes. Here are the first few steps of that tutorial translated to this approach.

Start with a black background layer and add a new transparent layer above it.
Set your FG color to green (74911d) and double-click on the Blend Tool
In the Tool Options dialog that appears, select the "FG to transparent" gradient and check the "Adaptive supersampling" box. Leave other options at their defaults (see screenshot below).
In your image window, draw a vertical stroke from the top of the image to the bottom (you can hold down the CTRL key while drawing to guarantee the line is vertical).


Next, open the Curves dialog ("Colors->Curves") and set the Channel to "Alpha".
Move the node in the upper-right to the left a little bit (this corresponds to the right "stop bit" in the tutorial).
Move the node in the lower-left up a little bit (this corresponds to the left "stop bit" in the tutorial). EDIT: This may not be correct (I do not have Photoshop available to check); it may be that moving the lower-left node horizontally to the right would correspond to changing the left "stop bit" in the tutorial.
Add a new node in the middle of the curve and adjust it to obtain a suitable result (control of this adjustment is not directly provided with the tutorial's approach).

Your result should be a green-to-black image that is more green than black.

(continued in next post)

To add the black radial gradient (basically a vignette), add a new transparent layer above the first two.
Change your FG color to black.
Open the Tool Options for the Blend Tool, change the Shape option to "Radial", and click on the "Reverse" option so you will be painting from "Transparent to FG" (as shown below).
Draw a stroke from the center of your image to one of the corners.
Note: the numeric value for angle and scale provided in the tutorial are effectively accomplished by this paint stroke. The angle is basically meaningless (for a radial gradient) and the length/scale is mainly intended to ensure that the gradient fully covers the image.

Same as before, the next step is to open the Curves dialog ("Colors->Curves") and set the Channel to "Alpha".
Move the node in the upper-right down a bit to lighten the gradient overall
Add a new node in the middle of the curve and adjust it to obtain a suitable result.
The resulting composited image:


(continued in next post)

Finally, the same basic process is repeated for the glow layer.

Add a new transparent layer.
Set your FG color to white.
Open the Tool Options for the Blend Tool and uncheck the "Reverse" option so that you are again painting a gradient from the FG color to transparency.
In the image window, draw a stroke from the upper-middle of the image to one of the lower corners. Again, the angle is not important but you do want it to be long enough to ensure that your gradient is smooth across the entire image.

For this layer, I recommend setting the Layer mode to "Overlay" to retain as much of the original color as you can (lightening it, rather than whitening it). You might want to drop the layer's opacity to 50% or so -- though this can be accomplished by editing the curves of the alpha channel, using the opacity setting helps to preserve the original color information (this precaution is mainly owing to GIMP's 8-bit color depth limitation).
Finally, use the Curves tool ("Colors->Curves") to adjust the Alpha channel, controlling the dispersion and brightness to produce the desired result.

Very well illustrated saul.
I am going to keep that bookmarked for reference, thanks.

saulgoode, that was extremely interesting, thank you for going into that much detail
i love stuff like that !

i do have a question however, i tried everything you showed in this tutorial and i have experimented before with the curves tool on the alpha channel, when i "researched" contours, but to be honest i dont understand fully what exactly is happening
so somehow i can manipulate the transparency (=alpha) to do what ?
"extend and retract"?



on a sidenote: this is interesting too
when i tried to copy a photoshopeffect with layerfx, it was almost only "programming" and it was extremely boring
it felt like im not longer creative
the program was expressing through me, not i was expressing myself with the help of the program

when looking at the christmas tree tutorial, it seems that PS can do loads of things by just pushing buttons, which is of course cool and when you try to replicate with Gimp a lot harder, but as i said above, it also feels "empty" to me

I just had tears roll down my face! that is an awesome tutorial my friend. it is getting book marked for sure. If you were here, i would make you the best streak you have ever had. Or i would put a prime rib on the smoker and invite all you all down here.

Thank you much for everyones expertise.

Matt

EDIT.

Ok, my two sentences are not enough of a thnaks to everyones pages and pages of info. I have learned so much about the gimp in the last two weeks than any other time. I tried to use earlier versions but didnt like them because i couldnt get the help.

On saturday, i tried to do some things in photoshop that i learned how to do in the gimp. Such as, take a picture of smoke coming off of some red lips, and use a full spectrum gradient under a transparent layer mask with a overlay on the layers blending mode, to color just the smoke. In the gimp it takes me like 3 minutes, i spent almost an hour trying to figure it out in PS and i couldnt get it to work. haha so i am proud to say that i can do more in the gimp 2.8.

[quote="Esper"


on a sidenote: this is interesting too
when i tried to copy a photoshopeffect with layerfx, it was almost only "programming" and it was extremely boring
it felt like im not longer creative
the program was expressing through me, not i was expressing myself with the help of the program

when looking at the christmas tree tutorial, it seems that PS can do loads of things by just pushing buttons, which is of course cool and when you try to replicate with Gimp a lot harder, but as i said above, it also feels "empty" to me[/quote]

Lol,i agree and a part of me says different. In times of being in a hurry, its nice to have the button push approach. But then there is the aspect of me wanting to learn how to do things. The christmas tree tutorial in PS should take 30 minutes max, it took me 2 hours to try and draw a tree using the paths tool. that tool is so hard to use and get curves the way you want. LOL. So to me i do like the quick and easy at certain times, but then again, that will happen with practice in the gimp.

Ok i followed the tutorial to a T and it works great. Question though so i understand why i did what i did. I tried the same tutorial using the FG to BG RGB gradient rather than the FG to transparent. What is the difference and why is it i need to use the FG to transparent? Also i noticed that with a standard gradient such as the FG to BG RGB, i cant use the colors>curves tool at all. no change is made when i adjust Value, red,green blue or alpha.

thanks

Matt

The problem with applying curves to a FG to BG gradient is that you end up shifting the hues of the gradient. By applying the curve to the alpha channel, you only change the amount of transparency of the color, not the color itself. If you experiment using the two techniques with gradient colors such as red to blue, or orange to green, then the difference will immediately become apparent. There is one exception to this, however. If the background color is black (as is the case with this tutorial) then changing the curve of the value channel behaves identically to changing the alpha channel.


Could you double-check what you are describing? You should have no problem editing the curves for FG to BG (RGB).

Interesting thoughts here, it is probably due to PS targeting professional audience where productivity is god. Does Gimp really prioritize creativity over productivity ? Now, I'm wondering.. (:

@saulgoode
this mini-tutorial was a complete revelation for me, probably the second most important "secret" Gimp technique (the first is stroking the path)

im now using this technique all the time and its really great !
so much more control

thanks again for taking the time to write this up !!!