Why the signal should be transformed into log2 form? - (Apr/21/2007 )

I am a new one for this technology. I just wonder why the signal from hybridization have to transformed into log2 form? Anybody who have the experience in this field help me please?

As far as my knowledge goes,

The signal that you get from any microarray is an integer which is taken as it is or made a ratio of using another number (in case of 2-color array) for futher analysis. Wherever this signal value is small, the ratio turns out huge, which many a times is a false positive e.g. 10/2 as opposed to 150/100 when two conditions are compared)
When you turn this value into log2 form, it avoids such issues and offers you a linear curve over your data and you avoid detection of these false positives.

I must say that its not easy to work with these log2 values if you are not a statistician as iot involves pretty complex calculations if you are using excel, like division of raw signals is same as subtraction of logged values etc. My suggestion would be, do your analysis using log2 data and when it comes to representation, get back to the natural values.

Post back if you don't understand what I mean.

Thank you very much for your kind help. I will read it and if I have something not clear, may I will interupt you again please .