Re: measuring uniform illumination

Posted by Richard Murray-3 on Mar 23, 2007; 1:15pm
URL: http://imagej.273.s1.nabble.com/measuring-uniform-illumination-tp3699972p3699976.html

Yes, you have been very helpful, thank you very much
--
Richard Murray BSc.
Nanoscale Biophotonics Research Group,
NCBES, Orbsen Biulding,
NUI Galway
Galway,
Ireland
email: [hidden email]
phone:[phone]

On Fri, March 23, 2007 12:01 pm, MUDr. Jakub Sikora said:

> There are several very nice review articles dealing with this issue:
> {Zucker, Cytometry, 2001), he suggests the use of flurescent plastic
> slides (Chroma sells these but others also), surface plot can be very
> nicely visualized when you apply LUT with defined percentage change,
> this can be done in ImageJ very easily, example of this is on the www in
> my signature, open the system evaluation (performed on confocal).
> Hope I helped
> Jakub
>
> Jakub Sikora M.D.
> Institute of Inherited Metabolic Disorders, 1st Medical Faculty, Charles
> University
> Ke Karlovu 2, Praha 2
> Czech Republic
> tel: [phone]
> mobile: [phone]
> fax: [phone]
> http://udmp.lf1.cuni.cz/web2/facility/microscope/microscopy.htm
>
> -----Original Message-----
> From: ImageJ Interest Group [mailto:[hidden email]] On Behalf Of
> Richard Murray
> Sent: Friday, March 23, 2007 12:32 PM
> To: [hidden email]
> Subject: Re: measuring uniform illumination
>
>
> Could I also use the surface plot to obtain the same result?
> --
> Richard Murray BSc.
> Nanoscale Biophotonics Research Group,
> NCBES, Orbsen Biulding,
> NUI Galway
> Galway,
> Ireland
> email: [hidden email]
> phone:[phone]
>
> On Thu, March 22, 2007 4:34 pm, John Oreopoulos said:
>> I think the easiest way to do this is snap a photo a blank sample with
>
>> your microscope that has been setup for Kohler illumination. It should
>
>> just look like featureless white image (make sure you're not
>> saturating your camera, turn down the exposure or light source voltage
>
>> if necessary). Then, using ImageJ, draw a long line anywhere on this
>> image and use the "plot profile" function which plots the pixel
>> intensity vs. the distance along this line that you've drawn. If you
>> have uniform illumination, then the variation in intensity along that
>> line should be 1% or less of the average value.
>>
>> I'm sure there might be other ways to check for uniformity, but I
>> think this is the simplest method.
>>
>>
>> John Oreopoulos, BSc,
>> PhD Candidate
>> University of Toronto
>> Institute For Biomaterials and Biomedical Engineering
>> Centre For Studies in Molecular Imaging
>>
>> Tel: W:416-946-5022
>>
>>
>>
>> On 22-Mar-07, at 11:28 AM, Richard Murray wrote:
>>
>>> Hi Everybody,
>>>
>>> Is it possible to use Image J to measure whether or not your getting
>>> uniform illumination using a point, line or field spread function?
>>> And if it is possible how would I go about doing this?
>>>
>>> Thanks in advance,
>>>
>>> Richard Murray
>>
>