Log Function

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Log Function

Martin, Richard W CTR USAF AFMC AFRL/RXLP
Maybe I have missed something, but I think the LOG function under
PROCESS-MATH-LOG does not work correctly. I am trying to take the LOG10
of each of the pixels in my image. I am using the 32-bit float format.
For instance if my pixel value is 2.01 then the LOG of it returns 0.670
for that pixel. Shouldn't the correct LOG be 0.301? What am I missing
here?

Thanks for your help.

 
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Re: Log Function

BenTupper
Hi,

I think you are getting the natural logarithm with that menu command.  
According to the docs (http://rsb.info.nih.gov/ij/docs/menus/process.html#math 
) you can simply transform to base 10 with a multiplier.

Cheers,
Ben


On Jun 23, 2009, at 4:42 PM, Martin, Richard W CTR USAF AFMC AFRL/RXLP  
wrote:

> Maybe I have missed something, but I think the LOG function under
> PROCESS-MATH-LOG does not work correctly. I am trying to take the  
> LOG10
> of each of the pixels in my image. I am using the 32-bit float format.
> For instance if my pixel value is 2.01 then the LOG of it returns  
> 0.670
> for that pixel. Shouldn't the correct LOG be 0.301? What am I missing
> here?
>
> Thanks for your help.
>
>

Ben Tupper