Hello, I work in forensic science and am teaching a lab at a university using the subtraction method for footwear and fingerprints.

Effectively I have 2 photographs taken using a tripod and the same lighting and camera settings (I have JPEG and NEF files for both photographs)
 - 1 is of a dusty partial footwear mark on a wooden floor
 - 1 is of the wooden floor but with the footwear mark completely cleaned away after the first photograph

I want to subtract the background (cleaned substrate) from the photograph showing the footwear mark, leaving only the footwear mark which will hopefully reveal more detail that was visibly lost in the wood grain background. The background can often interfere with visualising the print, especially with fingerprints and so the removal of the background can reveal fine details in ridges, valleys and pores etc.

I have experience using the subtraction method in Photoshop but as this is a university course I am unable to get multiple licences due to funding etc and so I have started playing around with GIMP instead.

I have tried a few methods I found online loading the images as layers and playing around with the subtraction and difference modes with some success but was wondering if there were any other settings/changes I could use to improve this? 

Also, is there an auto-align function in GIMP? e.g. solid lines between floorboards are aligned, not just the photographs themselves. As much as I try not to knock the tripod between photographs there sometimes can be very slight movement.

Thanks for your help/advice, David

To feel alive
   

Hi everyone,

It seems that Gimp Chat is not working correctly for me.
I was wondering if anybody else has experienced this.

Hi all,

New member here. For quite some time my GIMP 2.10's been working like a dream.

Now, however, the rectangle select tool is stuck on expand-from-center - a major time-waster rather than freely manipulating the four points of the rectangle. 

How on earth does one toggle it off? Many thanks!

Michael / fuguewriter

Posted this on the dead forum (why is it still there if it's dead?):

I mentioned this a year ago, but the problem is still there so I thought I'd shake the bushes a bit:  My Canon MG5220 printer doesn't work with GIMP.  It works flawlessly with every other application I have on my Debian stable distro.  As I've read elsewhere on the web, you do your modifications to an image in GIMP, then you save it and use another app to print it.  Really? 

The printer does nothing at all except that the little activity screen says that information is being received but nothing physical happens. It's exactly the same with Gutenprint or the 'normal' print.  Can't this be fixed guys? Every other app prints to the Canon without any trouble.  As it is, for simple work I'm now using fotoxx which prints fine, but I'd rather be using GIMP.

Hi,
Really new to everything, so please bear with me. When I use selection tools like ellipse or rectangle, the whole canvas starts sliding diagonally to the right bottom corner and lines become gradually thicker until everything kinda "melts". Started new files several times - no joy.  The attached screen shot shows rectangle selected around text after 2 seconds.
Any help will be greatly appreciated.

Attached Files

Thumbnail(s)
   

Hello,

I am trying to set GIMP up on an older 32 bit pc and it continually crashes.
It runs fine on my newer laptop.
Is there an older GIMP version that I can download that might run on the older machine.
Thank you
Neil

Im trying to bend text into a shape (the red lines on the left), but i get an error:

Exception: x=405.89 outside range for "top" envelope

Whats wrong with the envelope ?

As a test, i tried to rotate the shape so the ends of the waves align on the vertical. This worked okay, but its not what i want.
I want the text bent into a descending wave shape.

   

Hey guys, doing an obituary here, however, ran into some problems.

First off, I started this a few hours ago, saved it then came back to it so I'm not sure if it's my own fault where I forgot the settings for the Drop shadow creation but here we go:


The firs time I started the project the drop shadow looked like this:

https://i.imgur.com/ParqnCE.jpg


Look at the name/ in loving memory are all drop shadows with ONE drop shadow layer for each them.
However, the text had to have multiple drop shadows just to get the desired effect. Here's how it looks with only ONE drop shadow

https://i.imgur.com/nr5poGh.jpg

I cant for the life of me remember the drop shadow settings I used which were pretty normal:
Color: Black
Opacity: 100
Contour: Linear (I think, I never change it)
Noise (Always zero)
Blending Mode: Normal
Spread: o.o
Size (I tried changing it multiple times but one drop shadow layer still looked non-existent)
Offset Angle: 120
Offset DIstance: 5

Im not sure what I did to get such a dark/bold drop shadow the first time around from only one layer but I can't seem to duplicate it. Maybe it's the noise level? Is it possible to find how the options of a drop shadow layer in gimp as in what options were configured?
Here's a pic of the other layers with only one drop shadow

https://i.imgur.com/TzJeMdx.jpg

God, I just wasted time all over again signing up for this.
http://gimpforums.com/thread-selection--57412

Just wondering if there's some way to make whatever of the selection that goes out the boundary come in the other side. From here I can see four potential ways of doing that:

1: There's already a tool that does that
2: Use a random tool that crops the selection to whatever's out the boundary for some reason
3: The long way. Which I'm doing right now. It's kinda difficult to get the accuracy without taking a while. I just cut part of the object, paste it on the other side, align it on the edge where I want, get the first piece, get it on the same position of the axis perpendicular to the edge the cut piece is on to the cut piece and put it on the other side. Oh, also, I can't get anything past the edge, or it's gone.
4: Use a feature that doesn't delete whatever's out the boundary once it's unselected, and then one that can select whatever is.

Mostly what makes stuff difficult is how complicated the selection tool is. If this was Microsoft Paint I could just do it super fast without worrying about all the controls. But basically it just takes a while anyway in general.
By the way if it wasn't obvious already, I want to do a tiling. Bye.

P.S. The reason I signed up was to make this post. So don't care about my user.
Oh, yeah, I'm gonna search the forums in case there's already an answer.