I have a number of what I assume are basic questions?
(1) Is there a way to "checkpoint" or save a state when using the
gimp. Often I get to some state which I think is a good place to
progress from, try things and then want to back track to that state
if things don't go well. I know I can use Ctrl-Z (and increase the
undo stack depth), but it really would be nice to be able to "reset"
to some named state.
(2) Feathering and transparency.
I know that this is kitsch, but please advise on the technique anyway.
I am taking a simple snapshot of my daughter. Selecting an oval
around her (guide lines are very helpful for setting corners to an
oval I've discovered :-). I want that selection feathered (I can
do that), but with no background (or a transparent background).
What I've been doing is.
1) Opening gimp on the image file I have (JPEG)
1b) Image->Alpha->Setup Alpha Channel
2) Setting guide lines for my oval
3) Oval select
4) Feather selected (with 50.0000)
5) Edit->Copying to named buffer
6) Opening a new layer
7) Pasting named selection to new layer
8) Anchoring the "floating selection" to that new layer.
(I really don't understand that step at all)
9) Clearing the first (backround) layer (that had the whole photo)
Now here is where I've tried several things with varying results. And
I'm really not sure which sequences have lead to which results.
But roughly: If I fill the background layer with white, I can save
a new JPEG which has the feathered oval against a white background.
But if I leave the background clear instead of white, everything looks
correct in the Gimp, but when I save my image, I get either
(a) The oval UN-feathered against a transparent background, or
(b) Something that looks like the original (as if the background
had never been cleared).
I've tried saving as GIF and PNG, never getting a feathered oval against
a transparent background. Now as far as I understand, JPEGs, GIFs and
PNGs do have transparency (alpha channel).
I've also noticed that when I peek into to "challenges" list on the
"layers and channels" window, I only see R, G, and B, but no Alpha.
The image that I am starting with is large and high resolution. I
want to create something much smaller. Yet it seems to me that when
I use resize in the GIMP, it only shrinks its presentation to me of what
I am working on. What gets saved, still remains large.
Now that I know that Grokking the Gimp is available on-line, I will
check that out to see if it answers my questions. Feel free to answer (or
not) with RTFM (but if you could point me to specific chapters that would
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