Question about image stacking problem

[JeremyR1]

Hi,
I'm new to ImageJ.

I searched through the forum, but couldn't find an answer to this issue:
I'm trying to simply stack images. The images are all the same size, 8-bit
tif files.
Anytime I stack images, the second image and all following images in the
stack look different than their original source image - they have a more
pixelated look than their original source image. It looks almost as if some
thresholding or contrasting command is being automatically performed. The
first image of the stack looks unchanged compared to its original source
image.

Oddly enough, if I stack a couple copies of the same image, this doesn't
happen.
I tried resetting all the image adjusting parameters of the stacked image
(i.e. reset threshold, reset brightness/contrast, etc), but that didn't make
the stacked image look closer to the source image.

Has anyone encountered this, and know how to fix it?

I'm using ImageJ 1.42q, running on a Mac with OSX 10.5.8.

Thanks very much in advance,
Jeremy

[John Oreopoulos]

Jeremy,

When you stack images, they are all forced into the same brightness  
and contrast settings of the first image in the stack.

John Oreopoulos

On 7-Nov-09, at 8:19 AM, JeremyR1 wrote:

> Hi,
> I'm new to ImageJ.
>
> I searched through the forum, but couldn't find an answer to this  
> issue:
> I'm trying to simply stack images. The images are all the same  
> size, 8-bit
> tif files.
> Anytime I stack images, the second image and all following images  
> in the
> stack look different than their original source image - they have a  
> more
> pixelated look than their original source image. It looks almost as  
> if some
> thresholding or contrasting command is being automatically  
> performed. The
> first image of the stack looks unchanged compared to its original  
> source
> image.
>
> Oddly enough, if I stack a couple copies of the same image, this  
> doesn't
> happen.
> I tried resetting all the image adjusting parameters of the stacked  
> image
> (i.e. reset threshold, reset brightness/contrast, etc), but that  
> didn't make
> the stacked image look closer to the source image.
>
> Has anyone encountered this, and know how to fix it?
>
> I'm using ImageJ 1.42q, running on a Mac with OSX 10.5.8.
>
> Thanks very much in advance,
> Jeremy
> --
> View this message in context: http://n2.nabble.com/Question-about- 
> image-stacking-problem-tp3964128p3964128.html
> Sent from the ImageJ mailing list archive at Nabble.com.

[Wayne Rasband]

The Image>Stacks>Images to Stacks command does not work properly with  
8-bit color image. This will be fixed in the next daily build. In the  
meantime, you can work around the problem by converting each of the  
images to RGB (Image>Type>RGB Color) before using the Images to Stack  
command.

-wayne

On Nov 7, 2009, at 8:19 AM, JeremyR1 wrote:

 > Hi, I'm new to ImageJ.
 >
 > I searched through the forum, but couldn't find an answer to
 > this issue: I'm trying to simply stack images. The images
 > are all the same size, 8-bit tif files. Anytime I stack
 > images, the second image and all following images in the
 > stack look different than their original source image - they
 > have a more pixelated look than their original source image.
 > It looks almost as if some thresholding or contrasting
 > command is being automatically performed. The first image of
 > the stack looks unchanged compared to its original source
 > image.
 >
 > Oddly enough, if I stack a couple copies of the same image,
 > this doesn't happen. I tried resetting all the image
 > adjusting parameters of the stacked image (i.e. reset
 > threshold, reset brightness/contrast, etc), but that didn't
 > make the stacked image look closer to the source image.
 >
 > Has anyone encountered this, and know how to fix it?
 >
 > I'm using ImageJ 1.42q, running on a Mac with OSX 10.5.8.

[JeremyR1]

Thanks very much! I really appreciate it.

Jeremy

Wayne Rasband wrote:

The Image>Stacks>Images to Stacks command does not work properly with  
8-bit color image. This will be fixed in the next daily build. In the  
meantime, you can work around the problem by converting each of the  
images to RGB (Image>Type>RGB Color) before using the Images to Stack  
command.

-wayne

On Nov 7, 2009, at 8:19 AM, JeremyR1 wrote:

 > Hi, I'm new to ImageJ.
 >
 > I searched through the forum, but couldn't find an answer to
 > this issue: I'm trying to simply stack images. The images
 > are all the same size, 8-bit tif files. Anytime I stack
 > images, the second image and all following images in the
 > stack look different than their original source image - they
 > have a more pixelated look than their original source image.
 > It looks almost as if some thresholding or contrasting
 > command is being automatically performed. The first image of
 > the stack looks unchanged compared to its original source
 > image.
 >
 > Oddly enough, if I stack a couple copies of the same image,
 > this doesn't happen. I tried resetting all the image
 > adjusting parameters of the stacked image (i.e. reset
 > threshold, reset brightness/contrast, etc), but that didn't
 > make the stacked image look closer to the source image.
 >
 > Has anyone encountered this, and know how to fix it?
 >
 > I'm using ImageJ 1.42q, running on a Mac with OSX 10.5.8.