<div dir="ltr">I think I'll spend a day (week?) reading the Linuxtopia book.</div><div class="gmail_extra"><br><div class="gmail_quote">On Wed, Mar 23, 2016 at 4:13 PM, Brian Cluff <span dir="ltr"><<a href="mailto:brian@snaptek.com" target="_blank">brian@snaptek.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Here's some specifics of the blend modes.<br>
<a href="https://en.wikipedia.org/wiki/Blend_modes" rel="noreferrer" target="_blank">https://en.wikipedia.org/wiki/Blend_modes</a><br>
<a href="http://www.linuxtopia.org/online_books/graphics_tools/gimp_advanced_guide/gimp_guide_node55_002.html" rel="noreferrer" target="_blank">http://www.linuxtopia.org/online_books/graphics_tools/gimp_advanced_guide/gimp_guide_node55_002.html</a><br>
<br>
For your example pictures, screen will over brighten the darker areas of your picture, so dodge produces a better result. In a different picture, screen could be the better choice.<br>
<br>
Brian<span class=""><br>
<br>
On 03/23/2016 12:56 PM, Michael wrote:<br>
</span><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class="">
please, what is the difference between the two modes?<br>
<br>
On Wed, Mar 23, 2016 at 2:35 PM, Brian Cluff <<a href="mailto:brian@snaptek.com" target="_blank">brian@snaptek.com</a><br></span><div><div class="h5">
<mailto:<a href="mailto:brian@snaptek.com" target="_blank">brian@snaptek.com</a>>> wrote:<br>
<br>
Oops, use the Dodge layer mode instead of screen. You'll get better<br>
results.<br>
<br>
Brian<br>
<br>
<br>
On 03/23/2016 11:22 AM, Brian Cluff wrote:<br>
<br>
> On 03/23/2016 04:49 AM, Michael wrote:<br>
> Thanks Brian. I am putty in your hands!<br>
<br>
I get the bounces from the PLUG mailing list, so I got your<br>
images even<br>
though they were too big for the queue... nobody else did<br>
though, so my<br>
answer will be the only one based off your image.<br>
<br>
Anyway, looking at your pictures, it appears that the darkened edges<br>
aren't due to fading over time rather they are caused by what<br>
appear to<br>
be a flash going off that lit the center of the image more than the<br>
edges. This can also be caused of lower quality lenses giving you<br>
darkened edges in what is called a vignette.<br>
<br>
If you want to try and reduce/eliminate it, in gimp you would add a<br>
layer above your picture, but before you do that, if you have the<br>
option, go to Image -> Precision and set it to 16 ot 32 bit, so<br>
that you<br>
have more color data to work with. Unfortunately you'll only<br>
have that<br>
option if you are running the development version of GIMP, but<br>
it will<br>
still work OK if you can't do that setting. Next use the<br>
gradient tool,<br>
changing the gradient type to radial, and make a gradient that<br>
goes from<br>
black in the center fading to white at the corners. (draw the<br>
gradient<br>
from the center to one of the corners).<br>
<br>
Then set your new gradient layer's mode to "screen".<br>
<br>
At this point the effect will probably be too strong, so you<br>
will need<br>
to play with the opacity till it looks better and you can also<br>
play with<br>
the color curves moving the line on the lower left back and<br>
forth across<br>
the bottom to adjust the shape of the gradient till it better<br>
matches<br>
the vignette in your image. You can change the gradients layer mode<br>
back to normal to get an idea of what the color curve adjustment is<br>
doing to the gradient.<br>
<br>
Brian Cluff<br>
<br>
On 03/22/2016 06:42 PM, Brian Cluff wrote:<br>
<br>
Can you send an example so that I can see what you mean by<br>
"darkened<br>
around the edges"?<br>
<br>
I'll see if I can easily correct it and then send<br>
instructions on what I<br>
did.<br>
<br>
Brian Cluff<br>
<br>
On 03/22/2016 04:18 PM, Michael wrote:<br>
<br>
how does one use a transparent layer? is it only for<br>
drawing things on?<br>
I have some old pictures that have darkened around the<br>
edges. How I<br>
think I can fix it is to duplicate the layer then<br>
lighten the exposure<br>
value on the lower image, then paint black and uncover<br>
the lighter image<br>
over the section that has darkened. How do I do this<br>
with gradients and<br>
Darktable?<br>
<br>
--<br>
:-)~MIKE~(-:<br>
<br>
<br>
---------------------------------------------------<br>
PLUG-discuss mailing list -<br>
<a href="mailto:PLUG-discuss@lists.phxlinux.org" target="_blank">PLUG-discuss@lists.phxlinux.org</a><br></div></div>
<mailto:<a href="mailto:PLUG-discuss@lists.phxlinux.org" target="_blank">PLUG-discuss@lists.phxlinux.org</a>><span class=""><br>
To subscribe, unsubscribe, or to change your mail settings:<br>
<a href="http://lists.phxlinux.org/mailman/listinfo/plug-discuss" rel="noreferrer" target="_blank">http://lists.phxlinux.org/mailman/listinfo/plug-discuss</a><br>
<br>
---------------------------------------------------<br>
PLUG-discuss mailing list - <a href="mailto:PLUG-discuss@lists.phxlinux.org" target="_blank">PLUG-discuss@lists.phxlinux.org</a><br></span>
<mailto:<a href="mailto:PLUG-discuss@lists.phxlinux.org" target="_blank">PLUG-discuss@lists.phxlinux.org</a>><span class=""><br>
To subscribe, unsubscribe, or to change your mail settings:<br>
<a href="http://lists.phxlinux.org/mailman/listinfo/plug-discuss" rel="noreferrer" target="_blank">http://lists.phxlinux.org/mailman/listinfo/plug-discuss</a><br>
<br>
---------------------------------------------------<br>
PLUG-discuss mailing list - <a href="mailto:PLUG-discuss@lists.phxlinux.org" target="_blank">PLUG-discuss@lists.phxlinux.org</a><br></span>
<mailto:<a href="mailto:PLUG-discuss@lists.phxlinux.org" target="_blank">PLUG-discuss@lists.phxlinux.org</a>><span class=""><br>
To subscribe, unsubscribe, or to change your mail settings:<br>
<a href="http://lists.phxlinux.org/mailman/listinfo/plug-discuss" rel="noreferrer" target="_blank">http://lists.phxlinux.org/mailman/listinfo/plug-discuss</a><br>
<br>
---------------------------------------------------<br>
PLUG-discuss mailing list - <a href="mailto:PLUG-discuss@lists.phxlinux.org" target="_blank">PLUG-discuss@lists.phxlinux.org</a><br></span>
<mailto:<a href="mailto:PLUG-discuss@lists.phxlinux.org" target="_blank">PLUG-discuss@lists.phxlinux.org</a>><span class=""><br>
To subscribe, unsubscribe, or to change your mail settings:<br>
<a href="http://lists.phxlinux.org/mailman/listinfo/plug-discuss" rel="noreferrer" target="_blank">http://lists.phxlinux.org/mailman/listinfo/plug-discuss</a><br>
<br>
<br>
<br>
<br>
--<br>
:-)~MIKE~(-:<br>
<br>
<br></span><span class="">
---------------------------------------------------<br>
PLUG-discuss mailing list - <a href="mailto:PLUG-discuss@lists.phxlinux.org" target="_blank">PLUG-discuss@lists.phxlinux.org</a><br>
To subscribe, unsubscribe, or to change your mail settings:<br>
<a href="http://lists.phxlinux.org/mailman/listinfo/plug-discuss" rel="noreferrer" target="_blank">http://lists.phxlinux.org/mailman/listinfo/plug-discuss</a><br>
<br>
</span></blockquote><div class="HOEnZb"><div class="h5">
---------------------------------------------------<br>
PLUG-discuss mailing list - <a href="mailto:PLUG-discuss@lists.phxlinux.org" target="_blank">PLUG-discuss@lists.phxlinux.org</a><br>
To subscribe, unsubscribe, or to change your mail settings:<br>
<a href="http://lists.phxlinux.org/mailman/listinfo/plug-discuss" rel="noreferrer" target="_blank">http://lists.phxlinux.org/mailman/listinfo/plug-discuss</a><br>
</div></div></blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><span style="font-size:12.8000001907349px">:-)~MIKE~(-:</span><br></div></div></div></div></div>
</div>