Great thanks to both of you, Tesselator and Mulder.      :)
I got my answer completely.

--



"Smoothy" <bigvahid.antispam@hotmail.com> wrote in message
news:nIJDa.7933$VS5.649589@news20.bellglobal.com...
> Hey Tesselator,
>
> Thanks for your reply.
> CP2100 has only two levels of compression at 1600*1200, which are Fine
(1:4)
> and
> Normal (1:8).
> And yes, I took all of them at "Normal" setting.
>
> About the building, now I understand.
> I think I expected a little too much of my camera!    ;)
> The bright sky at the top, sun behind the building, and...
> > as if people were going not comming
> Is it a movie or a still picture?!
> JK! You're right, and it was sunset, a cloudy sunset to be more specific.
>
> Now if you don't mind, I can't understand something about these compressin
> ratios:
> The camera manual says that "Fine" is a 4:1 compression, well.
> But what this number has to do with the compression ratio I see in the
image
> properties?
> Numbers like 15.7, 9.8, 10.0, ...
> The least compression I could get from my camera (1600*1200, Fine) was
7.4.
> But even with the quality set to Fine, different pictures taken with the
> camera, have different
> compression ratios shown in my image viewing software; something between
7.4
> and 10.0.
> What's the reason for this?
>
>
> Cheers.           :o)
>
> --
>
>
>
> "Tesselator" <jimmmboe@hotmail.com> wrote in message
> news:bbn68i$peu$1@catv02.starcat.ne.jp...
> >
> > "Smoothy" <bigvahid.antispam@hotmail.com> wrote in message
> news:%czDa.11757$HG5.582599@news20.bellglobal.com...
> > > You are right, I didn't know it's not allowed to post images in this
> group.
> > > I put all the pictures in this address:
> > > http://www3.sympatico.ca/vahid.afra/
> > >
> > > And again you are right, when saving the crop, the JPEG compression
was
> on
> > > 65%,
> > > I thought it is on 100%.
> > > But the pictures which are uploaded on the above address, are all
> original.
> >
> >
> > If original then the camera compressed it.
> >
> > http://www3.sympatico.ca/vahid.afra/building.jpg is still 15.7
compression
> > ratio.  I believe the 2100 has 3 levels of JPEG and one level of
> uncompressed.
> > You had the setting on "Normal" right?  That's 15.7 jpeg.
> >
> >                                                                 O :-)
> >
> >
> > > Now I'd appreciate your comment about them.
> > > I myself think that all of them are grainy:
> > > Building Picture: the walls, ceiling, that parked car, ...
> >
> > I'd have to see an uncompressed version side by side to be sure
> (impossible now)
> > but as just a guess I'd say 70% of the noise you're seeing in that image
> was
> > introduced my the compression algorithm.  /I Think/ the other 30% or so
is
> due
> > to the fact that you've maxed out the dynamic range of the CCD with that
> particular
> > exposure (err, picture).  See how the sky is looking over exposed yet
the
> areas
> > under cars and even on the side of one car are underexposed?  That.
> >
> > I said "dynamic range of the CCD" and for this explaination that could
> suffice
> > even though the actual science is a little different.
> >
> >
> >
> > > Falls Picture: the sky and water
> > > Flowers Picture: all over the picture I notice grains...
> > > Tree Picture: the leaves
> >
> > The noise you see in these shots is 99.5% due to jpeg compression error.
> > The 1200x1600x24 shots would be about 5.7megs if uncompressed and the
> > 1024x768x24 shot of the flowers would be about 2.3 megs.
> >
> >
> >
> > > I wonder why it should be like this, they are all taken in daylight,
so
> > > there should be no effect like
> > > image noise (which usually noticable in night pictures with higher
ISO).
> > > This camera (Nikon Coolpix 2100) IS SUPPOSED to have sharp and crisp
> images!
> >
> > Yup I have a couple of coolpix too. They /are/ nice.  The shot you
picked
> > there is one of the toughest to get right...  IF it can even be done.
> > The sun has set behind that building but is still illuminating the BG
sky
> > and leaving the building face in the shadows.  Notice how the lamp-posts
> > are lit up?  I'ld say the camera did the best job possible under the
> > circumstances.  Ofcourse it /could/ be a sun-rise causing the same
> condition
> > but it looked to me as if people were going not comming so I assumed
dusk.
> >
> >
> >
> > > And thanks for your explanation about posting binaries.
> > >
> >
> > NP.
> >
> >         O :-)
>
>