Re: Basic gel band quantification questions

Posted by Herbie-6 on Jul 12, 2011; 2:29pm
URL: http://imagej.273.s1.nabble.com/Basic-gel-band-quantification-questions-tp3683947p3683948.html

Defne,

please specify what you mean by "reliable".

>Hi All,
>
>How reliable is quantification with ImageJ for an image that is
>converted to a TIFF, which had intially started out as a JPEG?

You won't loose any information by converting a JPEG-image to TIFF,
but if you are interested in scientific image evaluation, the use of
JPEG-images in the processing chain is definitely a no-no.

Although lossless JPEG-compression exists, JPEG generally means a
considerable loss of information and the introduction of artifacts.

>Also, although it is a recurring question, I would like to inquire
>on why certain
>TIFF images I have (of ethidium and coomassie stains) seem to
>randomly require a
>negative of the image/bands for correct quantification. Does this make the
>quantification less reliable, or is it just a matter of trusting the
>absolute values
>(the net difference from the background band)?

This question is up to those who are experineced in gel evaluation.

>Thank you very much,
>
>Defne

Best
--

                   Herbie

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