Aligning one image on top of an (almost identical) image

Is there any software (or feature in Photoshop) that will align one image
over another image that is almost identical? Ideally it could align a blue
image over the matching part of a red and green image.

I have some negative film, (accidentally) developed in E6 chemistry. The
result is that the red and green channels are very dark compared to the blue
channel.

I can adjust the gain (really the exposure) in NikonScan to get either the
red and green channel OR the blue channel, but nothing I have tried produces
an image with detail in all three channels.

As a result, I have 108 images with valid red and green channels, and 108
matching images with a valid blue channel. I need to align them properly,
preferably without having to do the whole thing by hand.

Thanks,
Aaron Queenan

 

Try alt.graphics.photoshop or comp.graphics.apps.photoshop

Don

 

Sorry, my mistake. I see you have already cross-posted :-(

Don

 

Drag and drop while holding the SHIFT key should align them perfectly.

 

"Aaron Queenan"
asked

Even doing it by hand, you would be restricted to increments of whole pixels.
The better way is to use the Optipix plugins (http://ReindeerGraphics.com) for
Photoshop. They include a routine that will automatically (using Fourier
Transform Cross-correlation) determine the offset of the images and apply
sub-pixel shifts for alignment. They also have routines that will blend images
that are over- and under-exposed, which might also be of interest in this
application.

 

Any photo editor that supports layers will do what you want, and
PhotoShop (and Elements) will do this.

 

The only thing I can think of would be to copy and paste in different
layers. Then adjust each layer for optimum. This adjustment should be
recorded as an 'Action' in Photoshop. Then it will be a simple matter of
calling up each picture paste and set the Action.

 

Yes - do what Johan says. Sheesh - it's not rocket science.

 

Well, that aligns image to center of layer, but does not necessarily
align one image to the other, if they aren't perfectly aligned to begin
with in reality (from camera,scanner, whatever originals).

You can of course reduce opacity of your top layer temporarily to see to
align but one is still doing it manually.

Mac

 

Not to mention that most of the methods suggested seem to be limited
to single-pixel resolution (you really want subpixel resolution) and
all of them seem to ignore the possibility of rotation or warp in
addition to a shift. A warp could come about from any inconsistency in
scan rate from frame to frame.

 

"stewy" {} wrote in message
}
} "Aaron Queenan" {} wrote in
message
} } } Is there any software (or feature in Photoshop) that will align one
image
} } over another image that is almost identical? Ideally it could align a
} blue
} } image over the matching part of a red and green image.
} }
} } I have some negative film, (accidentally) developed in E6 chemistry.
The
} } result is that the red and green channels are very dark compared to the
} blue
} } channel.
} }
} } I can adjust the gain (really the exposure) in NikonScan to get either
the
} } red and green channel OR the blue channel, but nothing I have tried
} produces
} } an image with detail in all three channels.
} }
} } As a result, I have 108 images with valid red and green channels, and
108
} } matching images with a valid blue channel. I need to align them
properly,
} } preferably without having to do the whole thing by hand.
} }
} The only thing I can think of would be to copy and paste in different
} layers. Then adjust each layer for optimum. This adjustment should be
} recorded as an 'Action' in Photoshop. Then it will be a simple matter of
} calling up each picture paste and set the Action.

Unfortunately, the x,y ofset for each image is different, because they were
scanned separately, so I'd really do with a program that aligns them
automatically.

Of course, I'd rather not pay too much for it, because it would only take a
few hours to do the job by hand, after all. *sigh*

Aaron.

 

"Mac McDougald" {} wrote in message
} In article {},
} says...
} }
} } "Johan W. Elzenga" {} wrote in message
} } } } } Aaron Queenan {} wrote:
} }
} } } Drag and drop while holding the SHIFT key should align them perfectly.
} }
} } Yes - do what Johan says. Sheesh - it's not rocket science.
}
} Well, that aligns image to center of layer, but does not necessarily
} align one image to the other, if they aren't perfectly aligned to begin
} with in reality (from camera,scanner, whatever originals).

That is the main problem. The red/green image and the blue image was
scanned separately for each negative (or strip of 4), so the top left
coordinate of the images vary.

At least the images seem to align well, i.e. aren't twisted, sheared,
warped, etc relative to each other.

Aaron.

 

"DrJohnRuss" {} wrote in message
} "Aaron Queenan"
} asked
}
} }Is there any software (or feature in Photoshop) that will align one image
} }over another image that is almost identical? Ideally it could align a
blue
} }image over the matching part of a red and green image.
} }
} }I have some negative film, (accidentally) developed in E6 chemistry. The
} }result is that the red and green channels are very dark compared to the
} }blue
} }channel.
} }
} }I can adjust the gain (really the exposure) in NikonScan to get either
the
} }red and green channel OR the blue channel, but nothing I have tried
produces
} }an image with detail in all three channels.
} }
} }As a result, I have 108 images with valid red and green channels, and 108
} }matching images with a valid blue channel. I need to align them
properly,
} }preferably without having to do the whole thing by hand.
}
} Even doing it by hand, you would be restricted to increments of whole
pixels.
} The better way is to use the Optipix plugins (http://ReindeerGraphics.com)
for
} Photoshop. They include a routine that will automatically (using Fourier
} Transform Cross-correlation) determine the offset of the images and apply
} sub-pixel shifts for alignment. They also have routines that will blend
images
} that are over- and under-exposed, which might also be of interest in this
} application.

Thanks, I'll give it a go.

Aaron.

 

Aaron (and all) I apologize for the misinformation. I did not remember that
you had separate scans to combine.

(For future references concerning combining images of a single subject which
has vastly different contrast ranges, you might want to look into HDRC.
Write if I need to elaborate.)

 

Here's how to do it:

1) Load the first image into PS
2) Temporarily increase the canvas size to give yourself moving about room.
3) Load the overlay image into a new layer
4) Set the new layer's blend mode to "Difference"
5) Use the Move Tool, keyboard, and mouse to size, shift, and rotate the
overlaid image to its best fit.
6) Set new layer's blending mode and opacity to whatever you need
7) Flatten and crop the new image

Voila!

I've done this to make transparent projections of topographical maps onto
aerial photos and to combine multiple digital camera exposures.

 

Here's the free & 'perfect' solution:

Use Hugin & Autopano to automatically determine the offset (in yaw,
pitch & roll) between pairs of images, then generate Photoshop
multilayer files from the results.

Hugin will do subpixel alignment & sampling.

Terje