double exposure
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| double exposure | jenn golden | 04 Nov 14:56 |
| double exposure | Richard Gitschlag | 04 Nov 15:10 |
| double exposure | Tobias Lunte | 04 Nov 15:18 |
| double exposure | Richard Gitschlag | 05 Nov 02:58 |
| double exposure | Richard Gitschlag | 05 Nov 19:01 |
| double exposure | yahvuu | 06 Nov 21:07 |
| double exposure | jenn golden | 07 Nov 02:31 |
| double exposure | vlastat60@gmail.com | 07 Nov 21:26 |
| double exposure | Patrick Shanahan | 07 Nov 21:33 |
double exposure
Is there a way to use this program to create a double exposure effect? I can do it with my 35mm camera manually while taking pics. But was not sure if you can create the same digitally??
Thank you! Jenn
double exposure
If it's the term I'm thinking of there are maybe twenty different ways to do this in GIMP. But all of them have one thing in common - you need to import both source images as separate layers in the same image window.
From that point you can: 1 - Set the top layer's mode to either Brightest or Addition (neither one precisely reproduces an actual double exposure, but they're close) 2 - Keep the top layer's mode Normal and use the Eraser (or a layer mask) to fade the edges/transition between them.
-- Stratadrake
strata_ranger@hotmail.com
--------------------
Numbers may not lie, but neither do they tell the whole truth.
Date: Sun, 4 Nov 2012 09:56:58 -0500
From: ellimae288@gmail.com
To: gimp-user-list@gnome.org
Subject: [Gimp-user] double exposure
Is there a way to use this program to create a double exposure effect? I can do it with my 35mm camera manually while taking pics. But was not sure if you can create the same digitally?? Thank you!
Jenn
gimp-user-list mailing list gimp-user-list@gnome.org https://mail.gnome.org/mailman/listinfo/gimp-user-list
double exposure
Hello,
afaik, the "Screen" blend mode is a more accurate reproduction of a double exposure. However, it will brighten up your image, so if the two photos weren't underexposed to begin with (which they are when you actually make a double-exposure on film), you'll have to adjust the values. Don't worry, the Screen mode doesn't result in clipping, so usually you don't loose all that much information.
bw, Tobl
Am 04.11.2012 16:10, schrieb Richard Gitschlag:
If it's the term I'm thinking of there are maybe twenty different ways to do this in GIMP. But all of them have one thing in common - you need to import both source images as separate layers in the same image window.
From that point you can: 1 - Set the top layer's mode to either Brightest or Addition (neither one precisely reproduces an actual double exposure, but they're close) 2 - Keep the top layer's mode Normal and use the Eraser (or a layer mask) to fade the edges/transition between them.
-- Stratadrake strata_ranger@hotmail.com
--------------------
Numbers may not lie, but neither do they tell the whole truth.------------------------------------------------------------------------ Date: Sun, 4 Nov 2012 09:56:58 -0500 From: ellimae288@gmail.com
To: gimp-user-list@gnome.org
Subject: [Gimp-user] double exposureIs there a way to use this program to create a double exposure effect? I can do it with my 35mm camera manually while taking pics. But was not sure if you can create the same digitally??
Thank you! Jenn
_______________________________________________ gimp-user-list mailing list gimp-user-list@gnome.org
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double exposure
Generally speaking, in terms of the resulting brightness when you blend two layers, Addition > Screen > Lighten Only.
The online GIMP manual explains layer blending modes in more detail (albeit not in the same order they are shown in actual GIMP 2.8's dropdown menu of blending modes :\ )
http://docs.gimp.org/2.8/en/gimp-concepts-layer-modes.html
-- Stratadrake
strata_ranger@hotmail.com
--------------------
Numbers may not lie, but neither do they tell the whole truth.
Date: Sun, 4 Nov 2012 16:18:39 +0100
From: tobias.lunte@hfg-gmuend.de
To: ellimae288@gmail.com
CC: gimp-user-list@gnome.org
Subject: Re: [Gimp-user] double exposure
Hello,
afaik, the "Screen" blend mode is a more accurate reproduction of a double exposure. However, it will brighten up your image, so if the two photos weren't underexposed to begin with (which they are when you actually make a double-exposure on film), you'll have to adjust the values. Don't worry, the Screen mode doesn't result in clipping, so usually you don't loose all that much information.
bw,
Tobl
Am 04.11.2012 16:10, schrieb Richard Gitschlag:
If it's the term I'm thinking of there are maybe twenty
different ways to do this in GIMP. But all of them have one
thing in common - you need to import both source images as
separate layers in the same image window.
From that point you can:
1 - Set the top layer's mode to either Brightest or Addition (neither one precisely reproduces an actual double exposure, but they're close)
2 - Keep the top layer's mode Normal and use the Eraser (or a layer mask) to fade the edges/transition between them.
-- Stratadrake
--------------------
Numbers may not lie, but neither do they tell the whole truth.
Date: Sun, 4 Nov 2012 09:56:58 -0500
From: ellimae288@gmail.com
Subject: [Gimp-user] double exposure
Is there a way to use this program to create a double exposure effect? I can do it with my 35mm camera manually while taking pics. But was not sure if you can create the same digitally??
Thank you!
Jenn
_______________________________________________
gimp-user-list mailing list
gimp-user-list@gnome.org
https://mail.gnome.org/mailman/listinfo/gimp-user-list
_______________________________________________
gimp-user-list mailing list
gimp-user-list@gnome.org
https://mail.gnome.org/mailman/listinfo/gimp-user-list
gimp-user-list mailing list gimp-user-list@gnome.org https://mail.gnome.org/mailman/listinfo/gimp-user-list
double exposure
PS: Since linear RGB pixels values are typically gamma-encoded representations of some absolutely recorded brightness, I suppose technically for a double-exposure you would have to un-encode the gamma (e.g. apply a Levels adjustment of 0.45 or so), merge the two source layers using Addition blending, then re-encode (e.g. 2.2 Levels adjustment). I did some experiments using two layers with black-to-white gradients rotated 90 degres from each other, and the result of those adjustments was indeed pretty close to the "Screen" blending mode. That's pretty interesting.
-- Stratadrake
strata_ranger@hotmail.com
--------------------
Numbers may not lie, but neither do they tell the whole truth.
Date: Sun, 4 Nov 2012 16:18:39 +0100
From: tobias.lunte@hfg-gmuend.de
To: ellimae288@gmail.com
CC: gimp-user-list@gnome.org
Subject: Re: [Gimp-user] double exposure
Hello,
afaik, the "Screen" blend mode is a more accurate reproduction of a double exposure. However, it will brighten up your image, so if the two photos weren't underexposed to begin with (which they are when you actually make a double-exposure on film), you'll have to adjust the values. Don't worry, the Screen mode doesn't result in clipping, so usually you don't loose all that much information.
bw,
Tobl
Am 04.11.2012 16:10, schrieb Richard Gitschlag:
If it's the term I'm thinking of there are maybe twenty
different ways to do this in GIMP. But all of them have one
thing in common - you need to import both source images as
separate layers in the same image window.
From that point you can:
1 - Set the top layer's mode to either Brightest or Addition (neither one precisely reproduces an actual double exposure, but they're close)
2 - Keep the top layer's mode Normal and use the Eraser (or a layer mask) to fade the edges/transition between them.
-- Stratadrake
--------------------
Numbers may not lie, but neither do they tell the whole truth.
Date: Sun, 4 Nov 2012 09:56:58 -0500
From: ellimae288@gmail.com
Subject: [Gimp-user] double exposure
Is there a way to use this program to create a double exposure effect? I can do it with my 35mm camera manually while taking pics. But was not sure if you can create the same digitally??
Thank you!
Jenn
_______________________________________________
gimp-user-list mailing list
gimp-user-list@gnome.org
https://mail.gnome.org/mailman/listinfo/gimp-user-list
_______________________________________________
gimp-user-list mailing list
gimp-user-list@gnome.org
https://mail.gnome.org/mailman/listinfo/gimp-user-list
gimp-user-list mailing list gimp-user-list@gnome.org https://mail.gnome.org/mailman/listinfo/gimp-user-list =
double exposure
Am 05.11.2012 20:01, schrieb Richard Gitschlag:
PS: Since linear RGB pixels values are typically gamma-encoded representations of some absolutely recorded brightness, I suppose technically for a double-exposure you would have to un-encode the gamma (e.g. apply a Levels adjustment of 0.45 or so), merge the two source layers using Addition blending, then re-encode (e.g. 2.2 Levels adjustment). I did some experiments using two layers with black-to-white gradients rotated 90 degres from each other, and the result of those adjustments was indeed pretty close to the "Screen" blending mode. That's pretty interesting.
this similarity is not by accident:
gamma curves can pretty closely resemble logarithms within the given value range and resolution: http://www.wolframalpha.com/input/?i=x^0.8%2C+ln%28x%2B1%29%2Fln%282%29+from+x%3D0+to+1
Adding the logarithms of two layers and subsequent un-logarithmising
gives the product of the layers:
ln(a) + ln(b) = ln(a*b)
a*b = exp( ln(a)+ln(b) )
The screen blend mode f(a,b) = 1-(1-a)*(1-b) can be read as multiplication, to be performed with inverted input layers and followed by inversion of the result.
best regards, peter
double exposure
I am really new to this program, and not even sure I did it correctly - but
see attached! I am very happy with the result! It looks like one I would
have done with a 35mm camera!
Jenn
On Tue, Nov 6, 2012 at 4:07 PM, yahvuu wrote:
Am 05.11.2012 20:01, schrieb Richard Gitschlag:
PS: Since linear RGB pixels values are typically gamma-encoded
representations of some absolutely
recorded brightness, I suppose technically for a double-exposure you
would have to un-encode the
gamma (e.g. apply a Levels adjustment of 0.45 or so), merge the two
source layers using Addition
blending, then re-encode (e.g. 2.2 Levels adjustment). I did some
experiments using two layers with
black-to-white gradients rotated 90 degres from each other, and the
result of those adjustments was
indeed pretty close to the "Screen" blending mode. That's pretty
interesting.
this similarity is not by accident:gamma curves can pretty closely resemble logarithms within the given value range and resolution:
http://www.wolframalpha.com/input/?i=x ^0.8%2C+ln%28x%2B1%29%2Fln%282%29+from+x%3D0+to+1Adding the logarithms of two layers and subsequent un-logarithmising gives the product of the layers:
ln(a) + ln(b) = ln(a*b)
a*b = exp( ln(a)+ln(b) )The screen blend mode f(a,b) = 1-(1-a)*(1-b) can be read as multiplication,
to be performed with inverted input layers and followed by inversion of the result.best regards,
peter
double exposure
Hi folks. I've been trying to leave the group. Nothing to do with Gimp( very nice app in my opinion), so I would really appreciate it if you all could help me out with this? Thanks for all the tips and tricks it's been a blast. Make sure to stop and take in whatever view your looking at. You never know what you might miss. Sent from my Verizon Wireless BlackBerry
-----Original Message-----
From: jenn golden
Sender: gimp-user-list-bounces@gnome.orgDate: Tue, 6 Nov 2012 21:31:18
To: yahvuu
Cc:
Subject: Re: [Gimp-user] double exposure
double exposure
* vlastat60@gmail.com [11-07-12 16:30]:
Hi folks. I've been trying to leave the group. Nothing to do with Gimp( very nice app in my opinion), so I would really appreciate it if you all could help me out with this? Thanks for all the tips and tricks it's been a blast. Make sure to stop and take in whatever view your looking at. You never know what you might miss. Sent from my Verizon Wireless BlackBerry
-----Original Message----- From: jenn golden
Sender: gimp-user-list-bounces@gnome.orgDate: Tue, 6 Nov 2012 21:31:18 To: yahvuu
Cc:
Subject: Re: [Gimp-user] double exposure_______________________________________________ gimp-user-list mailing list
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