Hello Francesco,

It is necessary to have more information about what you mean with “to remove the Background in TEM images” to answer your question correctly. Do you think a shading correction?

If yes, then the best way is a proper set-up of the on-line shading correction in the TEM software used for image acquisition.

If you would like to play with shading correction in the ImageJ, you would need:

- an Offset-image ( a camera offset image is acquired without any illumination.)

- for every magnification, you want o use, a Gain image (the camera gain image is acquired at homogeneous 50% illumination of scintillator without any specimen; TEM holder in parking position).

Then there is simple math:

- subtract the Offset image from the original image

- divide the product by the Gain image -> Corrected image

- multiply Corrected image by a mean grey value of the Gain image

All should be done at 16bit depth.

Other manipulation of TEM images might be pretty dangerous. Your attempts with ImageJ could easily fulfill the category of “Data beautification.” I would suggest the classical paper of Mike Rossner “What’s in a picture? The temptation of image manipulation.” (doi:10.1083/jcb.200406019). You can also check the “Image integrity and standards” from Nature editorial policies (https://www.nature.com/nature-research/editorial-policies/image-integrity#microscopy).

Regards

Oldrich

Why would you want to falsify TEM image?

I don't want falsify a TEM images, I just want improve the quality.

Thank you, it is exactly what I mean. Thank you for your answer !