densitometry on western blots

[Aawara Chowdhury]

In <wGk9h.197$Ll4.38 At newsfe04.lga>,
 DK <dk At no.email.thankstospam.net> wrote:

> In article <1164299514.092168.323980 At f16g2000cwb.googlegroups.com>, martinhoehne At gmx.net wrote:
>>Hello,
>>
>>I have some basic questions on densitometry and would be glad if anyone
>>can point me to a good source to learn more or even answers some of the
>>questions.
>>
>>1) As I understand it the bands have to be non-saturated. Does this
>>really mean that as soon as I have pixel values of 255 (on a 8-bit
>>image) I can forget about doing a densitometric analysis?
>
> No, it does not. 

That's not right.  For an 8-bit image, once a pixel value is at 255,
that pixel value cannot get any higher - by definition it is already
fully saturated.  Practically speaking, from an 8-bit image you get 
two logs of linearity.

It is for this reason that many of the commercial systems made by Kodak, 
Biorad, Alpha-Innotech etc. etc., make use of 10-bit or 12-bit CCDs.

AC
-- 
Email: echo 142322093203359315271794620168064975321554275890186P | dc