Posted by
Henry Barwood on
Aug 25, 2005; 4:42pm
URL: http://imagej.273.s1.nabble.com/Non-uniform-illumination-and-noise-reduction-tp3704964p3704971.html
I have found that taking a "blank" image (something like just a glass slide)
and subtracting this from the images works really well to even the
illumination. You have to adjust the blank using image math to get the right
degree of subtraction (too light and the resulting image will be dark, too
dark and you will have a very light result). Of course, this is time
consuming and I have not worked with a stack.
Henry Barwood
-----Original Message-----
From: ImageJ Interest Group [mailto:
[hidden email]]On Behalf Of
Michael Chelen
Sent: Thursday, August 25, 2005 9:30 AM
To:
[hidden email]
Subject: Non-uniform illumination and noise reduction
Hello,
I'm trying to analyze some calcium dye fluorescence images. The
illuminating field appears to be non-uniform, and I'm looking for a
good way to calculate and remove the background illumination. So far,
I've tried both the built-in "Subtract Background" command (Process ->
Subtract Background) and the plugin "Background Correction"
(
http://rsb.info.nih.gov/ij/plugins/background.html). These both to
seem to work reasonably well, but the second does not work for a
multiframe image. I was wondering if anyone had any experience with
these two tools, and if they could provide any insight into how these
tools work, and if there are others I should be considering.
Because the image set is a 500 frame t-series, it seems like the best
algorithm would be one that uses the data from every frame to
calculate the best possible approximation of the illuminating field.
Additionally, such a utility could identify likely points of noise
because the noise will change much more rapidly (from frame to frame)
than the actual signal. Is there anything like this for ImageJ that
anyone can recommend? I would really appreciate any suggestions or
insight.
Thanks,
Michael Chelen