Epson 4870 scan historgram settings cut off at 10, 245?

In Epson 4870's epson scan software, when in "professional" mode, the
historgram setting has both input and output limits default to 10, 245,
meaning anything darker than 10 will be output as 10, and anything brighter
than 245 will output as 245.

This means it loses 10 levels at the darkest and the brightest. Why is this
the default?
Wouldn't it be better to set the limits to 0, 255?

"peter" <nospam@nospam.com> wrote in message
news:55c%c.5408$5Y6.4549@trnddc07...
> In Epson 4870's epson scan software, when in "professional" mode, the
> historgram setting has both input and output limits default to 10, 245,
> meaning anything darker than 10 will be output as 10, and anything
> brighter
> than 245 will output as 245.
>
> This means it loses 10 levels at the darkest and the brightest. Why is
> this
> the default?
> Wouldn't it be better to set the limits to 0, 255?
>
>
Can you change the histogram setting? Most scanners use the histogram to set
the black and white points.

--
CSM1
http://www.carlmcmillan.com
--

Yes I can change it, but it's very annoying to have to set it everytime
before scanning.
Plus, I'm wondering perhaps there's a good reason for this setting to be
default.

I also tried vuescan, and it also defaults to something like that.
Strangely, I can change the upper limit to 255, but the lower limit cannot
be changed to 0.

"CSM1" <nomoremail@nomail.com> wrote in message
news:ZUj%c.17001$gF.12207@newssvr24.news.prodigy.com...
> "peter" <nospam@nospam.com> wrote in message
> news:55c%c.5408$5Y6.4549@trnddc07...
> > In Epson 4870's epson scan software, when in "professional" mode, the
> > historgram setting has both input and output limits default to 10, 245,
> > meaning anything darker than 10 will be output as 10, and anything
> > brighter
> > than 245 will output as 245.
> >
> > This means it loses 10 levels at the darkest and the brightest. Why is
> > this
> > the default?
> > Wouldn't it be better to set the limits to 0, 255?
> >
> >
> Can you change the histogram setting? Most scanners use the histogram to
set
> the black and white points.
>
> --
> CSM1
> http://www.carlmcmillan.com
> --
>

"peter" <nospam@nospam.com> wrote in message news:<HPp%c.8752$fF2.5978@trnddc03>...
> Yes I can change it, but it's very annoying to have to set it everytime
> before scanning.
> Plus, I'm wondering perhaps there's a good reason for this setting to be
> default.
>
> I also tried vuescan, and it also defaults to something like that.
> Strangely, I can change the upper limit to 255, but the lower limit cannot
> be changed to 0.

Peter, go to Google Groups and look up my "2 easy exposure questions"
post from a few months ago. The answer was that settings below the
0-255 maximum might prevent pure noise from creeping in at the
extremes, as well as producing a dynamic range more faithful to the
original (since pure white and black aren't all that common). But the
Epson settings aren't tailored to individual images--it seems as
though they're always 10-245 for prints and 10-200 for negatives. And
they mess up the auto color correction when they're changed. So they
are annoying (like most of the Epson Scan design).

false_dmitrii