Using log10 to analyse images

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Using log10 to analyse images

Godfrey Pasirayi
Dear members

I am kindly writing to seek your assistance in analysingimages using the log10 function.  Forexample I have two images A and B. I would like to perform the operation  Log 10 ( A/B) in image J to get image C. When I perform this operation theresultant  image C  is a black image with no features. Can someone in the group help me to dothis. I would like to see image C with all the features. My image A thebackground without the sample and Image B is the sample. So image C is theproduct only without the background contribution.

Godfrey Pasirayi


 

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Re: Using log10 to analyse images

Michael Schmid
Hi Godfrey,

when dividing images with Process>Image Calculator, make sure you check "32-bit result". Then use Process>Math>Log on the result, and divide (Process>Math>divide) by ln(10) = 2.302585093

Michael
________________________________________________________________
On Mar 27, 2015, at 13:34, Godfrey Pasirayi wrote:

> Dear members
>
> I am kindly writing to seek your assistance in analysingimages using the log10 function.  Forexample I have two images A and B. I would like to perform the operation  Log 10 ( A/B) in image J to get image C. When I perform this operation theresultant  image C is a black image with no features. Can someone in the group help me to dothis. I would like to see image C with all the features. My image A thebackground without the sample and Image B is the sample. So image C is theproduct only without the background contribution.
>
> Godfrey Pasirayi

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Re: Using log10 to analyse images

Godfrey Pasirayi
Thank you so much Michael for your response. However, the problem I am still facing is that the resulting image C is very dark with no features. For your information Images A and B are 16 bit. I am just wondering if there is any other conversion I need to do inorder to see the feature of image B without the background A. regards Godfrey


     On Friday, 27 March 2015, 12:53, Michael Schmid <[hidden email]> wrote:
   

 Hi Godfrey,

when dividing images with Process>Image Calculator, make sure you check "32-bit result". Then use Process>Math>Log on the result, and divide (Process>Math>divide) by ln(10) = 2.302585093

Michael
________________________________________________________________
On Mar 27, 2015, at 13:34, Godfrey Pasirayi wrote:

> Dear members
>
> I am kindly writing to seek your assistance in analysingimages using the log10 function.  Forexample I have two images A and B. I would like to perform the operation  Log 10 ( A/B) in image J to get image C. When I perform this operation theresultant  image C is a black image with no features. Can someone in the group help me to dothis. I would like to see image C with all the features. My image A thebackground without the sample and Image B is the sample. So image C is theproduct only without the background contribution.
>
> Godfrey Pasirayi

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ImageJ mailing list: http://imagej.nih.gov/ij/list.html


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