Re: Query regarding image processing

Posted by Herbie on Oct 18, 2020; 2:03pm
URL: http://imagej.273.s1.nabble.com/Query-regarding-image-processing-tp5024079p5024083.html

Igor,

attached please find the result of some pre-processing of a top right
square area of your sample image "sample 1 2".

It appears near to impossible to find an adequate thresholding scheme
that reflects a reasonable foreground / background relation, i.e. the
desired coverage.
(Using the "Default"-scheme I get a coverage in the investigated area of
about 50%.)

I still have problems interpreting sample image "sample 1 16" that shows
no detectable relation to sample image "sample 1 2".

Regards

Herbie

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Am 18.10.20 um 14:58 schrieb Igor Makarovsky:

> Dear Gabriel,
> I tried to send the original image, but it was too big to send (5.76 MB)
> and not 4M that the nih mail restricted. So I photographed the image and
> sent it for your appreciation. Please find the original image attached via
> wetransfer (https://we.tl/t-Td7yO8gKSI). What I need to do is to determine
> the percentage of the nano-sized particles in the image. I deliberately
> chose this particular image because you can see both sizes. The bigger
> lumps are the micro particles or clusters of nano-sized particles
> aglomerated together and the background is laced with nano particles
> (please find another image - a higher magnification). I thought doing area
> fraction calculation, but not sure this is the right technique, because the
> bigger lumps are also covered in these nano needles.
>
> Thank you for your help,
> Igor
>
> On Sun, 18 Oct 2020 at 15:20, Gabriel Landini <[hidden email]> wrote:
>
>> On Sunday, 18 October 2020 11:33:00 BST [hidden email] wrote:
>>> I have a series of SEM
>>> images, from which I have to calculate the relative percentage of the
>>> Nano-sized particles.
>>
>> If the scale bar (10 micrometres) is correct, I am afraid that you cannot
>> image nanoparticles at that magnification. Nanoparticles are normally
>> defined
>> as having between 1 and 100 nanometres in diameter, not micrometres!
>>
>> Cheers
>>
>> Gabriel

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