Re: trouble specifying a ROI in ROI Manager

Posted by Joris FA Meys on Feb 13, 2009; 10:08am
URL: http://imagej.273.s1.nabble.com/Macros-to-read-and-write-Complex-Fourier-Transform-tp3693680p3693683.html

The measurements should be fairly simple with the ROI manager. Just click on
the roi you specified earlier, and drag it to where you want to measure.
First click "Add", because otherwise the ROI manager will measure at the
previous position. That should give you the results you want.

Kind regards
Joris


On Fri, Feb 13, 2009 at 4:36 AM, Hugo A. M. Torres <[hidden email]>wrote:

> Hello listmates,
>
> I am trying to perform densitometry measurements according to this
> method:
>
> "The nucleus was encircled by free-hand drawing of a border around the
> outermost mRNA-expressing cells in the nucleus. The mean density and the
> area of the selection were measured. The mean density of the background
> was measured from a rectangular area of corresponding size in the
> immediate vicinity of the nucleus. The mean density of the background
> was subtracted from the mean density of the nucleus and..."
>
> Now, the problem is I can't specify a ROI of the same area of the place
> I measured previously. I tried taking the square root of the area (given
> in um^2) and specifying a square ROI with sides of this length but the
> resulting area measured is always smaller!
>
> Is it possible to specify a square ROI by inputing  an area value in
> square micrometers?
>
> Thanks
> --
> Hugo Arruda de Moura Torres
> ==================================
> Departamento de Biofísica
> Universidade Federal de São Paulo
> Rua Botucatu 862 7o. andar
>